NEVGOLD ANNOUNCES MINERAL RESOURCE: ANTIMONY OF 29,600 TONNES MEASURED & INDICATED (0.26%) AND 48,100 TONNES INFERRED (0.18%); 100% OXIDE GOLD OF 181,400 OZS MEASURED & INDICATED AND 1,203,500 OZS INFERRED; STRATEGIC U.S. ANTIMONY RESOURCE

Original announcement by tmx on

Company
NevGold Corp.
Ticker
NAU
Exchange
TSX
Region
Nevada
Primary commodity
Antimony
Secondary commodities
Gold, Silver
Document categories
Resource update
Extracted
2026-09-12 14:39:35 UTC

Analysis by Minestarters Atlas

Minestarters Atlas analysis

Summary

NevGold Corp. announced a maiden Mineral Resource Estimate for its Limo Butte Project in Nevada, defining 29,600 tonnes of Measured & Indicated antimony (0.26%) and 48,100 tonnes of Inferred antimony (0.18%). The estimate also includes 181,400 ounces of Measured & Indicated oxide gold (0.37 g/t) and 1,203,500 ounces of Inferred oxide gold (0.32 g/t). This MRE establishes a strategic U.S. antimony resource and provides a pathway for potential near-term antimony production from already mined surface material, with significant expansion potential identified for future drilling.

Reasoning: NevGold announced its maiden Mineral Resource Estimate for the Limo Butte Project, establishing a significant gold-antimony resource in Nevada. The MRE includes substantial Measured and Indicated resources for both commodities, with a focus on strategic antimony supply and oxide gold. The estimate is NI 43-101 compliant and provides a strong foundation for future project development, including potential near-term antimony production.

Positive factors

  • Maiden Mineral Resource Estimate for gold and antimony
  • Defines a strategic U.S. antimony resource
  • Includes Measured, Indicated, and Inferred categories for both commodities
  • 100% oxide gold amenable to heap leaching
  • NI 43-101 compliant and signed off by a Qualified Person
  • Potential for near-term antimony production from surface material
  • Significant potential for resource expansion with ongoing drill programs

Negative factors

  • High proportion of Inferred resources (87% of total gold ounces, 72% of total antimony tonnes)
  • No prior MRE for direct comparison of growth metrics

Low confidence — this extraction should be reviewed alongside the original source.

Facts used in scoring: 73

Classification and evidence

Maiden Resourceneutral

First formal MRE for the project — establishes baseline but typically exploration-stage with high Inferred component. No prior estimate exists, so every change band is not applicable.

Why it applies: The document explicitly states this is NevGold's 'maiden gold-antimony Mineral Resource Estimate'.

Evidence · text

“NevGold is pleased to announce its maiden gold-antimony Mineral Resource Estimate (“ MRE ”)”

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: Mr. Greg Mosher (P.Geo., M.Sc. Applied), Principal of GMRS, is named as an independent 'Qualified Person' under NI 43-101 and is responsible for the MRE.

Evidence · text

“Mr. Greg Mosher (P.Geo., M.Sc. Applied), Principal of GMRS is an independent “Qualified Person” under NI 43-101 and is responsible for the MRE.”

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: The mineral resources have been estimated in accordance with Canadian Institute of Mining, Metallurgy and Petroleum definitions, as required under National Instrument 43-101.

Evidence · text

“All mineral resources have been estimated in accordance with Canadian Institute of Mining, Metallurgy and Petroleum definitions, as required under National Instrument 43-101 (“ NI 43-101 ”).”

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: The document clearly states various cut-off grades used for the resource estimate, including 0.30 g/t AuEq., 0.15 g/t Au, and 0.1% Sb.

Evidence · text

“Mineral Resources for Leach Pads, Pre-Strip Dump, Resurrection, and Cadillac Valley are reported at a cut-off grade of 0.30 g/t AuEq.”

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: A significant portion of the resource is classified as Inferred, including 1,203,500 oz of gold and 48,100 tonnes of antimony.

Evidence · text

“1,203,500 OZS INFERRED; STRATEGIC U.S. ANTIMONY RESOURCE”

Measured Resourcepositive

Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves.

Why it applies: The MRE includes Measured resources, such as 9,500 oz gold and 2,600 tonnes antimony in the Leach Pads zone.

Evidence · table

“Measured”

Context: Leach Pads

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: The MRE includes Indicated resources, such as 171,900 oz gold and 27,000 tonnes antimony across various zones.

Evidence · table

“Indicated”

Context: Leach Pads

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: The company states 'Preliminary Economic Assessment (“PEA”) on Resurrection Ridge, Cadillac Valley, and Northern Zones focused on gold-antimony' as a next step.

Evidence · text

“Preliminary Economic Assessment (“PEA”) on Resurrection Ridge, Cadillac Valley, and Northern Zones focused on gold-antimony”

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: The company states 'Further metallurgical testwork to advance the Project to a Prefeasibility Study (“PFS”)' as a next step.

Evidence · text

“Further metallurgical testwork to advance the Project to a Prefeasibility Study (“PFS”) on the near-term antimony production scenario”

Extracted facts

Stored fact records: 73. Some facts used in scoring do not have a stored record.

Resource Estimates (73)

measuredLimo Butte · goldTonnes: 1000000Grade: 0.31Grade Unit: g/tContained Metal: 9500Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:90c985faa1065a5e4f66
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
measured
Tonnes
1000000
Grade
0.31
Grade Unit
g/t
Contained Metal
9500
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured resource for gold in the Leach Pads zone, contributing to the overall project's initial resource definition.

Positive factors

  • Maiden Measured resource for gold
  • Part of a strategic dual-commodity MRE

Evidence · table

“0.31”

Context: 1.0

Tags used in scoring

Measured Resourcepositive

Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves.

Why it applies: category is "measured"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

measuredLimo Butte · silverTonnes: 1000000Grade: 2.8Grade Unit: g/tContained Metal: 87000Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:90c985faa1065a5e4f66
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
measured
Tonnes
1000000
Grade
2.8
Grade Unit
g/t
Contained Metal
87000
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured resource for silver in the Leach Pads zone, providing byproduct potential within the overall resource.

Positive factors

  • Maiden Measured resource for silver
  • Byproduct credit in a dual-commodity MRE

Evidence · table

“2.80”

Context: 1.0

Tags used in scoring

Measured Resourcepositive

Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves.

Why it applies: category is "measured"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

measuredLimo Butte · antimonyTonnes: 1000000Grade: 0.26Grade Unit: %Contained Metal: 2600Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:90c985faa1065a5e4f66
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
measured
Tonnes
1000000
Grade
0.26
Grade Unit
%
Contained Metal
2600
Contained Unit
t
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured resource for antimony in the Leach Pads zone, representing a component of the strategic U.S. antimony resource.

Positive factors

  • Maiden Measured resource for strategic antimony
  • Contributes to potential near-term production from surface material

Evidence · table

“0.26%”

Context: 1.0

Tags used in scoring

Measured Resourcepositive

Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves.

Why it applies: category is "measured"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 1200000Grade: 0.29Grade Unit: g/tContained Metal: 11600Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:d3191bbeee227ee46769
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
1200000
Grade
0.29
Grade Unit
g/t
Contained Metal
11600
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for gold in the Leach Pads zone, contributing to the project's initial resource definition.

Positive factors

  • Maiden Indicated resource for gold
  • Adds to the overall gold resource base

Evidence · table

“0.29”

Context: 1.2

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 1200000Grade: 2.43Grade Unit: g/tContained Metal: 96700Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:d3191bbeee227ee46769
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
1200000
Grade
2.43
Grade Unit
g/t
Contained Metal
96700
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for silver in the Leach Pads zone, adding to the project's byproduct potential.

Positive factors

  • Maiden Indicated resource for silver
  • Provides byproduct potential

Evidence · table

“2.43”

Context: 1.2

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 1200000Grade: 0.3Grade Unit: %Contained Metal: 3700Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:d3191bbeee227ee46769
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
1200000
Grade
0.3
Grade Unit
%
Contained Metal
3700
Contained Unit
t
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for antimony in the Leach Pads zone, adding to the strategic U.S. antimony resource.

Positive factors

  • Maiden Indicated resource for strategic antimony
  • Contributes to potential near-term production from surface material

Evidence · table

“0.30%”

Context: 1.2

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 90000Grade: 0.3Grade Unit: g/tContained Metal: 900Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:92632e8794bcf5c1e752
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
90000
Grade
0.3
Grade Unit
g/t
Contained Metal
900
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for gold in the Pre-Strip Dump zone, contributing to the initial resource definition from existing material.

Positive factors

  • Maiden Indicated resource for gold
  • From already mined material

Evidence · table

“0.30”

Context: 0.09

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 90000Grade: 0.13Grade Unit: g/tContained Metal: 400Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:92632e8794bcf5c1e752
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
90000
Grade
0.13
Grade Unit
g/t
Contained Metal
400
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for silver in the Pre-Strip Dump zone, adding to the project's byproduct potential.

Positive factors

  • Maiden Indicated resource for silver
  • Provides byproduct potential

Evidence · table

“0.13”

Context: 0.09

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 90000Grade: 0.65Grade Unit: %Contained Metal: 600Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:92632e8794bcf5c1e752
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
90000
Grade
0.65
Grade Unit
%
Contained Metal
600
Contained Unit
t
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for antimony in the Pre-Strip Dump zone, contributing to the strategic U.S. antimony resource from existing material.

Positive factors

  • Maiden Indicated resource for strategic antimony
  • Higher grade antimony from already mined material

Evidence · table

“0.65%”

Context: 0.09

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 12900000Grade: 0.38Grade Unit: g/tContained Metal: 159400Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:da132a9cc76c1ca88d96
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
12900000
Grade
0.38
Grade Unit
g/t
Contained Metal
159400
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for gold in the Resurrection zone, representing the largest Indicated gold component of the MRE.

Positive factors

  • Maiden Indicated resource for gold
  • Largest Indicated gold component in the MRE

Evidence · table

“0.38”

Context: 12.9

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 12900000Grade: 0.91Grade Unit: g/tContained Metal: 378100Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:da132a9cc76c1ca88d96
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
12900000
Grade
0.91
Grade Unit
g/t
Contained Metal
378100
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for silver in the Resurrection zone, providing significant byproduct potential.

Positive factors

  • Maiden Indicated resource for silver
  • Significant byproduct potential

Evidence · table

“0.91”

Context: 12.9

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 12900000Grade: 0.19Grade Unit: %Contained Metal: 24900Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:da132a9cc76c1ca88d96
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
12900000
Grade
0.19
Grade Unit
%
Contained Metal
24900
Contained Unit
t
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for antimony in the Resurrection zone, representing the largest Indicated antimony component of the MRE.

Positive factors

  • Maiden Indicated resource for strategic antimony
  • Largest Indicated antimony component in the MRE

Evidence · table

“0.19%”

Context: 12.9

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 15200000Grade: 0.37Grade Unit: g/tContained Metal: 181400Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:1b71f8b181607908d139
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
15200000
Grade
0.37
Grade Unit
g/t
Contained Metal
181400
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Measured & Indicated resource for gold, providing a substantial base of higher-confidence gold ounces for the project.

Positive factors

  • Maiden Measured & Indicated resource for gold
  • Significant gold ounces in higher confidence categories

Evidence · table

“0.37”

Context: 15.2

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 15200000Grade: 1.15Grade Unit: g/tContained Metal: 562200Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:1b71f8b181607908d139
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
15200000
Grade
1.15
Grade Unit
g/t
Contained Metal
562200
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Measured & Indicated resource for silver, offering substantial byproduct potential in higher confidence categories.

Positive factors

  • Maiden Measured & Indicated resource for silver
  • Significant byproduct potential in higher confidence categories

Evidence · table

“1.15”

Context: 15.2

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 15200000Grade: 0.21Grade Unit: %Contained Metal: 31800Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:1b71f8b181607908d139
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
15200000
Grade
0.21
Grade Unit
%
Contained Metal
31800
Contained Unit
t
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Measured & Indicated resource for antimony, establishing a substantial strategic antimony base in higher confidence categories.

Positive factors

  • Maiden Measured & Indicated resource for strategic antimony
  • Significant antimony tonnes in higher confidence categories

Evidence · table

“0.21%”

Context: 15.2

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 50000Grade: 0.28Grade Unit: g/tContained Metal: 400Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:4ec10cfa03eacaa0658e
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
50000
Grade
0.28
Grade Unit
g/t
Contained Metal
400
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold in the Pre-Strip Dump zone, contributing to the overall resource from existing material.

Positive factors

  • Maiden Inferred resource for gold
  • From already mined material

Negative factors

  • Lower confidence category

Evidence · table

“0.28”

Context: 0.05

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 50000Grade: 0.03Grade Unit: g/tContained Metal: 40Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:4ec10cfa03eacaa0658e
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
50000
Grade
0.03
Grade Unit
g/t
Contained Metal
40
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for silver in the Pre-Strip Dump zone, adding to the overall resource with low grade.

Positive factors

  • Maiden Inferred resource for silver

Negative factors

  • Lower confidence category
  • Very low grade

Evidence · table

“0.03”

Context: 0.05

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 50000Grade: 0.99Grade Unit: %Contained Metal: 500Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:4ec10cfa03eacaa0658e
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
50000
Grade
0.99
Grade Unit
%
Contained Metal
500
Contained Unit
t
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for antimony in the Pre-Strip Dump zone, contributing to the strategic U.S. antimony resource with high grade.

Positive factors

  • Maiden Inferred resource for strategic antimony
  • High grade antimony from already mined material

Negative factors

  • Lower confidence category

Evidence · table

“0.99%”

Context: 0.05

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 28500000Grade: 0.29Grade Unit: g/tContained Metal: 261600Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:f93714e3b7998cf40e78
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
28500000
Grade
0.29
Grade Unit
g/t
Contained Metal
261600
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold in the Resurrection zone, adding significant gold ounces to the overall resource.

Positive factors

  • Maiden Inferred resource for gold
  • Significant gold ounces

Negative factors

  • Lower confidence category

Evidence · table

“0.29”

Context: 28.5

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 28500000Grade: 0.87Grade Unit: g/tContained Metal: 799100Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:f93714e3b7998cf40e78
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
28500000
Grade
0.87
Grade Unit
g/t
Contained Metal
799100
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for silver in the Resurrection zone, providing significant byproduct potential.

Positive factors

  • Maiden Inferred resource for silver
  • Significant byproduct potential

Negative factors

  • Lower confidence category

Evidence · table

“0.87”

Context: 28.5

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 28500000Grade: 0.12Grade Unit: %Contained Metal: 34600Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:f93714e3b7998cf40e78
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
28500000
Grade
0.12
Grade Unit
%
Contained Metal
34600
Contained Unit
t
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for antimony in the Resurrection zone, adding significant antimony tonnes to the strategic U.S. resource.

Positive factors

  • Maiden Inferred resource for strategic antimony
  • Significant antimony tonnes

Negative factors

  • Lower confidence category

Evidence · table

“0.12%”

Context: 28.5

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 57200000Grade: 0.37Grade Unit: g/tContained Metal: 686500Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:0f0d8c9c43ae478f1a7e
Deposit or zone
Cadillac Valley
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
57200000
Grade
0.37
Grade Unit
g/t
Contained Metal
686500
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold in the Cadillac Valley zone, representing the largest Inferred gold component of the MRE.

Positive factors

  • Maiden Inferred resource for gold
  • Largest Inferred gold component in the MRE

Negative factors

  • Lower confidence category

Evidence · table

“0.37”

Context: 57.2

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 57200000Grade: 0.49Grade Unit: g/tContained Metal: 895700Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:0f0d8c9c43ae478f1a7e
Deposit or zone
Cadillac Valley
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
57200000
Grade
0.49
Grade Unit
g/t
Contained Metal
895700
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for silver in the Cadillac Valley zone, providing significant byproduct potential.

Positive factors

  • Maiden Inferred resource for silver
  • Significant byproduct potential

Negative factors

  • Lower confidence category

Evidence · table

“0.49”

Context: 57.2

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 57200000Grade: 0.07Grade Unit: %Contained Metal: 40600Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:0f0d8c9c43ae478f1a7e
Deposit or zone
Cadillac Valley
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
57200000
Grade
0.07
Grade Unit
%
Contained Metal
40600
Contained Unit
t
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for antimony in the Cadillac Valley zone, representing the largest Inferred antimony component of the MRE.

Positive factors

  • Maiden Inferred resource for strategic antimony
  • Largest Inferred antimony component in the MRE

Negative factors

  • Lower confidence category

Evidence · table

“0.07%”

Context: 57.2

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 31700000Grade: 0.25Grade Unit: g/tContained Metal: 255000Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:7fbd01d4a43bf622f201
Deposit or zone
Northern Zones
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
31700000
Grade
0.25
Grade Unit
g/t
Contained Metal
255000
Contained Unit
oz
Cutoff Grade
0.15
Cutoff Unit
g/t Au

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold in the Northern Zones, adding significant gold ounces to the overall resource, with a lower gold-only cut-off.

Positive factors

  • Maiden Inferred resource for gold
  • Significant gold ounces

Negative factors

  • Lower confidence category
  • No antimony data currently available

Evidence · table

“0.25”

Context: 31.7

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 117500000Grade: 0.32Grade Unit: g/tContained Metal: 1203500Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:9ad8dd32a1e7bb4198ee
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
117500000
Grade
0.32
Grade Unit
g/t
Contained Metal
1203500
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Inferred resource for gold, representing a very large gold endowment with significant future potential.

Positive factors

  • Maiden Inferred resource for gold
  • Very large gold ounces, indicating significant potential

Negative factors

  • Lower confidence category

Evidence · table

“0.32”

Context: 117.5

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 117500000Grade: 0.61Grade Unit: g/tContained Metal: 1694840Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:9ad8dd32a1e7bb4198ee
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
117500000
Grade
0.61
Grade Unit
g/t
Contained Metal
1694840
Contained Unit
oz
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Inferred resource for silver, indicating very large byproduct potential for the project.

Positive factors

  • Maiden Inferred resource for silver
  • Very large byproduct potential

Negative factors

  • Lower confidence category

Evidence · table

“0.61”

Context: 117.5

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 117500000Grade: 0.09Grade Unit: %Contained Metal: 75700Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:9ad8dd32a1e7bb4198ee
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
117500000
Grade
0.09
Grade Unit
%
Contained Metal
75700
Contained Unit
t
Cutoff Grade
0.3
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Inferred resource for antimony, representing a very large strategic antimony endowment with significant future potential.

Positive factors

  • Maiden Inferred resource for strategic antimony
  • Very large antimony tonnes, indicating significant potential

Negative factors

  • Lower confidence category

Evidence · table

“0.09%”

Context: 117.5

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

measuredLimo Butte · goldTonnes: 1000000Grade: 0.31Grade Unit: g/tContained Metal: 9500Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:90c985faa1065a5e4f66
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
measured
Tonnes
1000000
Grade
0.31
Grade Unit
g/t
Contained Metal
9500
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured resource for gold in the Leach Pads zone, reported within the antimony sub-domain, contributing to the overall project's initial resource definition.

Positive factors

  • Maiden Measured resource for gold within antimony sub-domain
  • Part of a strategic dual-commodity MRE

Evidence · table

“0.31”

Context: 1.0

Tags used in scoring

Measured Resourcepositive

Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves.

Why it applies: category is "measured"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

measuredLimo Butte · silverTonnes: 1000000Grade: 2.8Grade Unit: g/tContained Metal: 87000Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:90c985faa1065a5e4f66
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
measured
Tonnes
1000000
Grade
2.8
Grade Unit
g/t
Contained Metal
87000
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured resource for silver in the Leach Pads zone, reported within the antimony sub-domain, providing byproduct potential.

Positive factors

  • Maiden Measured resource for silver within antimony sub-domain
  • Byproduct credit in a dual-commodity MRE

Evidence · table

“2.80”

Context: 1.0

Tags used in scoring

Measured Resourcepositive

Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves.

Why it applies: category is "measured"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

measuredLimo Butte · antimonyTonnes: 1000000Grade: 0.26Grade Unit: %Contained Metal: 2600Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:90c985faa1065a5e4f66
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
measured
Tonnes
1000000
Grade
0.26
Grade Unit
%
Contained Metal
2600
Contained Unit
t
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured resource for antimony in the Leach Pads zone, reported within the antimony sub-domain, representing a component of the strategic U.S. antimony resource.

Positive factors

  • Maiden Measured resource for strategic antimony within antimony sub-domain
  • Contributes to potential near-term production from surface material

Evidence · table

“0.26%”

Context: 1.0

Tags used in scoring

Measured Resourcepositive

Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves.

Why it applies: category is "measured"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 1200000Grade: 0.29Grade Unit: g/tContained Metal: 11600Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:d3191bbeee227ee46769
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
1200000
Grade
0.29
Grade Unit
g/t
Contained Metal
11600
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for gold in the Leach Pads zone, reported within the antimony sub-domain, contributing to the project's initial resource definition.

Positive factors

  • Maiden Indicated resource for gold within antimony sub-domain
  • Adds to the overall gold resource base

Evidence · table

“0.29”

Context: 1.2

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 1200000Grade: 2.44Grade Unit: g/tContained Metal: 96700Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:d3191bbeee227ee46769
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
1200000
Grade
2.44
Grade Unit
g/t
Contained Metal
96700
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for silver in the Leach Pads zone, reported within the antimony sub-domain, adding to the project's byproduct potential.

Positive factors

  • Maiden Indicated resource for silver within antimony sub-domain
  • Provides byproduct potential

Evidence · table

“2.44”

Context: 1.2

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 1200000Grade: 0.3Grade Unit: %Contained Metal: 3700Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:d3191bbeee227ee46769
Deposit or zone
Leach Pads
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
1200000
Grade
0.3
Grade Unit
%
Contained Metal
3700
Contained Unit
t
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for antimony in the Leach Pads zone, reported within the antimony sub-domain, adding to the strategic U.S. antimony resource.

Positive factors

  • Maiden Indicated resource for strategic antimony within antimony sub-domain
  • Contributes to potential near-term production from surface material

Evidence · table

“0.30%”

Context: 1.2

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 90000Grade: 0.3Grade Unit: g/tContained Metal: 900Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:92632e8794bcf5c1e752
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
90000
Grade
0.3
Grade Unit
g/t
Contained Metal
900
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for gold in the Pre-Strip Dump zone, reported within the antimony sub-domain, contributing to the initial resource definition from existing material.

Positive factors

  • Maiden Indicated resource for gold within antimony sub-domain
  • From already mined material

Evidence · table

“0.30”

Context: 0.09

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 90000Grade: 0.13Grade Unit: g/tContained Metal: 400Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:92632e8794bcf5c1e752
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
90000
Grade
0.13
Grade Unit
g/t
Contained Metal
400
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for silver in the Pre-Strip Dump zone, reported within the antimony sub-domain, adding to the project's byproduct potential.

Positive factors

  • Maiden Indicated resource for silver within antimony sub-domain
  • Provides byproduct potential

Evidence · table

“0.13”

Context: 0.09

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 90000Grade: 0.65Grade Unit: %Contained Metal: 600Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:92632e8794bcf5c1e752
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
90000
Grade
0.65
Grade Unit
%
Contained Metal
600
Contained Unit
t
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for antimony in the Pre-Strip Dump zone, reported within the antimony sub-domain, contributing to the strategic U.S. antimony resource from existing material.

Positive factors

  • Maiden Indicated resource for strategic antimony within antimony sub-domain
  • Higher grade antimony from already mined material

Evidence · table

“0.65%”

Context: 0.09

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 9100000Grade: 0.37Grade Unit: g/tContained Metal: 107500Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:f42f579dc5900dbd347a
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
9100000
Grade
0.37
Grade Unit
g/t
Contained Metal
107500
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for gold in the Resurrection zone, reported within the antimony sub-domain, representing a significant gold component of the MRE.

Positive factors

  • Maiden Indicated resource for gold within antimony sub-domain
  • Significant gold ounces

Evidence · table

“0.37”

Context: 9.1

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 9100000Grade: 0.97Grade Unit: g/tContained Metal: 283500Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:f42f579dc5900dbd347a
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
9100000
Grade
0.97
Grade Unit
g/t
Contained Metal
283500
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for silver in the Resurrection zone, reported within the antimony sub-domain, providing significant byproduct potential.

Positive factors

  • Maiden Indicated resource for silver within antimony sub-domain
  • Significant byproduct potential

Evidence · table

“0.97”

Context: 9.1

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 9100000Grade: 0.25Grade Unit: %Contained Metal: 22700Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:f42f579dc5900dbd347a
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
9100000
Grade
0.25
Grade Unit
%
Contained Metal
22700
Contained Unit
t
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Indicated resource for antimony in the Resurrection zone, reported within the antimony sub-domain, representing a significant antimony component of the MRE.

Positive factors

  • Maiden Indicated resource for strategic antimony within antimony sub-domain
  • Significant antimony tonnes

Evidence · table

“0.25%”

Context: 9.1

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 11300000Grade: 0.36Grade Unit: g/tContained Metal: 129500Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:393a1737a0c0da836fbc
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
11300000
Grade
0.36
Grade Unit
g/t
Contained Metal
129500
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Measured & Indicated resource for gold, reported within the antimony sub-domain, providing a substantial base of higher-confidence gold ounces.

Positive factors

  • Maiden Measured & Indicated resource for gold within antimony sub-domain
  • Significant gold ounces in higher confidence categories

Evidence · table

“0.36”

Context: 11.3

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 11300000Grade: 1.28Grade Unit: g/tContained Metal: 467600Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:393a1737a0c0da836fbc
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
11300000
Grade
1.28
Grade Unit
g/t
Contained Metal
467600
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Measured & Indicated resource for silver, reported within the antimony sub-domain, offering substantial byproduct potential.

Positive factors

  • Maiden Measured & Indicated resource for silver within antimony sub-domain
  • Significant byproduct potential in higher confidence categories

Evidence · table

“1.28”

Context: 11.3

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 11300000Grade: 0.26Grade Unit: %Contained Metal: 29600Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:393a1737a0c0da836fbc
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
11300000
Grade
0.26
Grade Unit
%
Contained Metal
29600
Contained Unit
t
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Measured & Indicated resource for antimony, reported within the antimony sub-domain, establishing a substantial strategic antimony base.

Positive factors

  • Maiden Measured & Indicated resource for strategic antimony within antimony sub-domain
  • Significant antimony tonnes in higher confidence categories

Evidence · table

“0.26%”

Context: 11.3

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 40000Grade: 0.28Grade Unit: g/tContained Metal: 400Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:306797daea922d5df451
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
40000
Grade
0.28
Grade Unit
g/t
Contained Metal
400
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold in the Pre-Strip Dump zone, reported within the antimony sub-domain, contributing to the overall resource from existing material.

Positive factors

  • Maiden Inferred resource for gold within antimony sub-domain
  • From already mined material

Negative factors

  • Lower confidence category

Evidence · table

“0.28”

Context: 0.04

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 40000Grade: 0.03Grade Unit: g/tContained Metal: 40Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:306797daea922d5df451
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
40000
Grade
0.03
Grade Unit
g/t
Contained Metal
40
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for silver in the Pre-Strip Dump zone, reported within the antimony sub-domain, adding to the overall resource with low grade.

Positive factors

  • Maiden Inferred resource for silver within antimony sub-domain

Negative factors

  • Lower confidence category
  • Very low grade

Evidence · table

“0.03”

Context: 0.04

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 40000Grade: 1.02Grade Unit: %Contained Metal: 500Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:306797daea922d5df451
Deposit or zone
Pre-Strip Dump
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
40000
Grade
1.02
Grade Unit
%
Contained Metal
500
Contained Unit
t
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for antimony in the Pre-Strip Dump zone, reported within the antimony sub-domain, contributing to the strategic U.S. antimony resource with high grade.

Positive factors

  • Maiden Inferred resource for strategic antimony within antimony sub-domain
  • High grade antimony from already mined material

Negative factors

  • Lower confidence category

Evidence · table

“1.02%”

Context: 0.04

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 14100000Grade: 0.19Grade Unit: g/tContained Metal: 87300Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:6d0b9239e6f59555ed6e
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
14100000
Grade
0.19
Grade Unit
g/t
Contained Metal
87300
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold in the Resurrection zone, reported within the antimony sub-domain, adding significant gold ounces to the overall resource.

Positive factors

  • Maiden Inferred resource for gold within antimony sub-domain
  • Significant gold ounces

Negative factors

  • Lower confidence category

Evidence · table

“0.19”

Context: 14.1

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 14100000Grade: 0.61Grade Unit: g/tContained Metal: 275700Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:6d0b9239e6f59555ed6e
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
14100000
Grade
0.61
Grade Unit
g/t
Contained Metal
275700
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for silver in the Resurrection zone, reported within the antimony sub-domain, providing significant byproduct potential.

Positive factors

  • Maiden Inferred resource for silver within antimony sub-domain
  • Significant byproduct potential

Negative factors

  • Lower confidence category

Evidence · table

“0.61”

Context: 14.1

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 14100000Grade: 0.2Grade Unit: %Contained Metal: 27600Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:6d0b9239e6f59555ed6e
Deposit or zone
Resurrection
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
14100000
Grade
0.2
Grade Unit
%
Contained Metal
27600
Contained Unit
t
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for antimony in the Resurrection zone, reported within the antimony sub-domain, adding significant antimony tonnes to the strategic U.S. resource.

Positive factors

  • Maiden Inferred resource for strategic antimony within antimony sub-domain
  • Significant antimony tonnes

Negative factors

  • Lower confidence category

Evidence · table

“0.20%”

Context: 14.1

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 12700000Grade: 0.26Grade Unit: g/tContained Metal: 108400Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:957b924033c46257ecff
Deposit or zone
Cadillac Valley
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
12700000
Grade
0.26
Grade Unit
g/t
Contained Metal
108400
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold in the Cadillac Valley zone, reported within the antimony sub-domain, adding significant gold ounces to the overall resource.

Positive factors

  • Maiden Inferred resource for gold within antimony sub-domain
  • Significant gold ounces

Negative factors

  • Lower confidence category

Evidence · table

“0.26”

Context: 12.7

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 12700000Grade: 0.53Grade Unit: g/tContained Metal: 218100Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:957b924033c46257ecff
Deposit or zone
Cadillac Valley
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
12700000
Grade
0.53
Grade Unit
g/t
Contained Metal
218100
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for silver in the Cadillac Valley zone, reported within the antimony sub-domain, providing significant byproduct potential.

Positive factors

  • Maiden Inferred resource for silver within antimony sub-domain
  • Significant byproduct potential

Negative factors

  • Lower confidence category

Evidence · table

“0.53”

Context: 12.7

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 12700000Grade: 0.16Grade Unit: %Contained Metal: 20000Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:957b924033c46257ecff
Deposit or zone
Cadillac Valley
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
12700000
Grade
0.16
Grade Unit
%
Contained Metal
20000
Contained Unit
t
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for antimony in the Cadillac Valley zone, reported within the antimony sub-domain, adding significant antimony tonnes to the strategic U.S. resource.

Positive factors

  • Maiden Inferred resource for strategic antimony within antimony sub-domain
  • Significant antimony tonnes

Negative factors

  • Lower confidence category

Evidence · table

“0.16%”

Context: 12.7

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 26900000Grade: 0.23Grade Unit: g/tContained Metal: 196100Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:58cfcb33730376b92117
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
26900000
Grade
0.23
Grade Unit
g/t
Contained Metal
196100
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Inferred resource for gold, reported within the antimony sub-domain, representing a large gold endowment with significant future potential.

Positive factors

  • Maiden Inferred resource for gold within antimony sub-domain
  • Large gold ounces, indicating significant potential

Negative factors

  • Lower confidence category

Evidence · table

“0.23”

Context: 26.9

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 26900000Grade: 0.57Grade Unit: g/tContained Metal: 493840Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:58cfcb33730376b92117
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
26900000
Grade
0.57
Grade Unit
g/t
Contained Metal
493840
Contained Unit
oz
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Inferred resource for silver, reported within the antimony sub-domain, indicating large byproduct potential for the project.

Positive factors

  • Maiden Inferred resource for silver within antimony sub-domain
  • Large byproduct potential

Negative factors

  • Lower confidence category

Evidence · table

“0.57”

Context: 26.9

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 26900000Grade: 0.18Grade Unit: %Contained Metal: 48100Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:58cfcb33730376b92117
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
26900000
Grade
0.18
Grade Unit
%
Contained Metal
48100
Contained Unit
t
Cutoff Grade
0.1
Cutoff Unit
% Sb

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden total Inferred resource for antimony, reported within the antimony sub-domain, representing a large strategic antimony endowment with significant future potential.

Positive factors

  • Maiden Inferred resource for strategic antimony within antimony sub-domain
  • Large antimony tonnes, indicating significant potential

Negative factors

  • Lower confidence category

Evidence · table

“0.18%”

Context: 26.9

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 8900000Grade: 0.51Grade Unit: g/tContained Metal: 144200Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:348d67635810fe9c8f90
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
8900000
Grade
0.51
Grade Unit
g/t
Contained Metal
144200
Contained Unit
oz
Cutoff Grade
0.6
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured & Indicated resource for gold at a higher cut-off grade, showing improved gold grade for a smaller tonnage.

Positive factors

  • Maiden Measured & Indicated resource for gold at higher cut-off
  • Higher gold grade

Evidence · table

“0.51”

Context: 8.9

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 8900000Grade: 1.41Grade Unit: g/tContained Metal: 400000Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:348d67635810fe9c8f90
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
8900000
Grade
1.41
Grade Unit
g/t
Contained Metal
400000
Contained Unit
oz
Cutoff Grade
0.6
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured & Indicated resource for silver at a higher cut-off grade, showing improved silver grade for a smaller tonnage.

Positive factors

  • Maiden Measured & Indicated resource for silver at higher cut-off
  • Higher silver grade

Evidence · table

“1.41”

Context: 8.9

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 8900000Grade: 0.28Grade Unit: %Contained Metal: 25100Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:348d67635810fe9c8f90
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
8900000
Grade
0.28
Grade Unit
%
Contained Metal
25100
Contained Unit
t
Cutoff Grade
0.6
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured & Indicated resource for antimony at a higher cut-off grade, showing improved antimony grade for a smaller tonnage.

Positive factors

  • Maiden Measured & Indicated resource for strategic antimony at higher cut-off
  • Higher antimony grade

Evidence · table

“0.28%”

Context: 8.9

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 51800000Grade: 0.41Grade Unit: g/tContained Metal: 690700Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:f0414df01b6e8ad01802
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
51800000
Grade
0.41
Grade Unit
g/t
Contained Metal
690700
Contained Unit
oz
Cutoff Grade
0.6
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold at a higher cut-off grade, showing improved gold grade for a smaller tonnage.

Positive factors

  • Maiden Inferred resource for gold at higher cut-off
  • Higher gold grade

Negative factors

  • Lower confidence category

Evidence · table

“0.41”

Context: 51.8

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 51800000Grade: 1.08Grade Unit: g/tContained Metal: 700220Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:f0414df01b6e8ad01802
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
51800000
Grade
1.08
Grade Unit
g/t
Contained Metal
700220
Contained Unit
oz
Cutoff Grade
0.6
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for silver at a higher cut-off grade, showing improved silver grade for a smaller tonnage.

Positive factors

  • Maiden Inferred resource for silver at higher cut-off
  • Higher silver grade

Negative factors

  • Lower confidence category

Evidence · table

“1.08”

Context: 51.8

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 51800000Grade: 0.14Grade Unit: %Contained Metal: 28600Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:f0414df01b6e8ad01802
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
51800000
Grade
0.14
Grade Unit
%
Contained Metal
28600
Contained Unit
t
Cutoff Grade
0.6
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for antimony at a higher cut-off grade, showing improved antimony grade for a smaller tonnage.

Positive factors

  • Maiden Inferred resource for strategic antimony at higher cut-off
  • Higher antimony grade

Negative factors

  • Lower confidence category

Evidence · table

“0.14%”

Context: 51.8

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 11300000Grade: 0.44Grade Unit: g/tContained Metal: 160600Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:393a1737a0c0da836fbc
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
11300000
Grade
0.44
Grade Unit
g/t
Contained Metal
160600
Contained Unit
oz
Cutoff Grade
0.45
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured & Indicated resource for gold at an intermediate cut-off grade, showing good gold grade for a moderate tonnage.

Positive factors

  • Maiden Measured & Indicated resource for gold at intermediate cut-off
  • Good gold grade

Evidence · table

“0.44”

Context: 11.3

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 11300000Grade: 1.28Grade Unit: g/tContained Metal: 463100Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:393a1737a0c0da836fbc
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
11300000
Grade
1.28
Grade Unit
g/t
Contained Metal
463100
Contained Unit
oz
Cutoff Grade
0.45
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured & Indicated resource for silver at an intermediate cut-off grade, showing good silver grade for a moderate tonnage.

Positive factors

  • Maiden Measured & Indicated resource for silver at intermediate cut-off
  • Good silver grade

Evidence · table

“1.28”

Context: 11.3

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 11300000Grade: 0.25Grade Unit: %Contained Metal: 28400Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:393a1737a0c0da836fbc
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
11300000
Grade
0.25
Grade Unit
%
Contained Metal
28400
Contained Unit
t
Cutoff Grade
0.45
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured & Indicated resource for antimony at an intermediate cut-off grade, showing good antimony grade for a moderate tonnage.

Positive factors

  • Maiden Measured & Indicated resource for strategic antimony at intermediate cut-off
  • Good antimony grade

Evidence · table

“0.25%”

Context: 11.3

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 70300000Grade: 0.38Grade Unit: g/tContained Metal: 868000Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:35b42a2b922543fa8306
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
70300000
Grade
0.38
Grade Unit
g/t
Contained Metal
868000
Contained Unit
oz
Cutoff Grade
0.45
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold at an intermediate cut-off grade, showing good gold grade for a large tonnage.

Positive factors

  • Maiden Inferred resource for gold at intermediate cut-off
  • Good gold grade

Negative factors

  • Lower confidence category

Evidence · table

“0.38”

Context: 70.3

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 70300000Grade: 0.83Grade Unit: g/tContained Metal: 1036340Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:35b42a2b922543fa8306
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
70300000
Grade
0.83
Grade Unit
g/t
Contained Metal
1036340
Contained Unit
oz
Cutoff Grade
0.45
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for silver at an intermediate cut-off grade, showing good silver grade for a large tonnage.

Positive factors

  • Maiden Inferred resource for silver at intermediate cut-off
  • Good silver grade

Negative factors

  • Lower confidence category

Evidence · table

“0.83”

Context: 70.3

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 70300000Grade: 0.12Grade Unit: %Contained Metal: 46000Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:35b42a2b922543fa8306
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
70300000
Grade
0.12
Grade Unit
%
Contained Metal
46000
Contained Unit
t
Cutoff Grade
0.45
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for antimony at an intermediate cut-off grade, showing good antimony grade for a large tonnage.

Positive factors

  • Maiden Inferred resource for strategic antimony at intermediate cut-off
  • Good antimony grade

Negative factors

  • Lower confidence category

Evidence · table

“0.12%”

Context: 70.3

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · goldTonnes: 23100000Grade: 0.28Grade Unit: g/tContained Metal: 204900Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:6f44f7dfbc37ec4b34e1
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
23100000
Grade
0.28
Grade Unit
g/t
Contained Metal
204900
Contained Unit
oz
Cutoff Grade
0.15
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured & Indicated resource for gold at a lower cut-off grade, showing increased tonnage with a lower gold grade.

Positive factors

  • Maiden Measured & Indicated resource for gold at lower cut-off
  • Increased tonnage

Evidence · table

“0.28”

Context: 23.1

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · silverTonnes: 23100000Grade: 0.98Grade Unit: g/tContained Metal: 729300Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:6f44f7dfbc37ec4b34e1
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
23100000
Grade
0.98
Grade Unit
g/t
Contained Metal
729300
Contained Unit
oz
Cutoff Grade
0.15
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured & Indicated resource for silver at a lower cut-off grade, showing increased tonnage with a lower silver grade.

Positive factors

  • Maiden Measured & Indicated resource for silver at lower cut-off
  • Increased tonnage

Evidence · table

“0.98”

Context: 23.1

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

indicatedLimo Butte · antimonyTonnes: 23100000Grade: 0.16Grade Unit: %Contained Metal: 36100Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:6f44f7dfbc37ec4b34e1
Mining method
open_pit

Resource Data

Category
indicated
Tonnes
23100000
Grade
0.16
Grade Unit
%
Contained Metal
36100
Contained Unit
t
Cutoff Grade
0.15
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Measured & Indicated resource for antimony at a lower cut-off grade, showing increased tonnage with a lower antimony grade.

Positive factors

  • Maiden Measured & Indicated resource for strategic antimony at lower cut-off
  • Increased tonnage

Evidence · table

“0.16%”

Context: 23.1

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · goldTonnes: 221900000Grade: 0.23Grade Unit: g/tContained Metal: 1628900Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
gold
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:8e0fcaf4186f8685686f
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
221900000
Grade
0.23
Grade Unit
g/t
Contained Metal
1628900
Contained Unit
oz
Cutoff Grade
0.15
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for gold at a lower cut-off grade, showing significantly increased tonnage and contained ounces, albeit with a lower grade.

Positive factors

  • Maiden Inferred resource for gold at lower cut-off
  • Significantly increased tonnage and contained ounces

Negative factors

  • Lower confidence category

Evidence · table

“0.23”

Context: 221.9

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · silverTonnes: 221900000Grade: 0.49Grade Unit: g/tContained Metal: 2997940Contained Unit: ozView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
silver
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:8e0fcaf4186f8685686f
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
221900000
Grade
0.49
Grade Unit
g/t
Contained Metal
2997940
Contained Unit
oz
Cutoff Grade
0.15
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for silver at a lower cut-off grade, showing significantly increased tonnage and contained ounces, albeit with a lower grade.

Positive factors

  • Maiden Inferred resource for silver at lower cut-off
  • Significantly increased tonnage and contained ounces

Negative factors

  • Lower confidence category

Evidence · table

“0.49”

Context: 221.9

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

inferredLimo Butte · antimonyTonnes: 221900000Grade: 0.06Grade Unit: %Contained Metal: 114000Contained Unit: tView all details
Link to this fact

Identity

Project
Limo Butte
Commodity
antimony
Region
usa_nv
Reported Region
Nevada
Ticker
NAU

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Greg Mosher
Resource group id
resource:8e0fcaf4186f8685686f
Mining method
open_pit

Resource Data

Category
inferred
Tonnes
221900000
Grade
0.06
Grade Unit
%
Contained Metal
114000
Contained Unit
t
Cutoff Grade
0.15
Cutoff Unit
g/t AuEq.

Prior Estimate

Resource Date
2026-07-15

Metal Equivalent

Assumptions Disclosed
Yes

Lab

Laboratory
American Assay Labs, Reno

Location

Loc. Confidence
medium

Review

Needs Review
No
Historical
No

Dates

Event date
2026-07-15T00:00:00.000Z

Reasoning: Maiden Inferred resource for antimony at a lower cut-off grade, showing significantly increased tonnage and contained tonnes, albeit with a lower grade.

Positive factors

  • Maiden Inferred resource for strategic antimony at lower cut-off
  • Significantly increased tonnage and contained tonnes

Negative factors

  • Lower confidence category

Evidence · table

“0.06%”

Context: 221.9

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

Qualified Person (QP) or Competent Person (CP) named and signed off — a member of a recognized professional association (e.g., AusIMM, SME, AIG, P.Geo) with relevant experience.

Why it applies: qp_signed is true

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

PFS-Supportingneutral

Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.

Why it applies: the release names the study this estimate supports

How Atlas produces this analysis

Minestarters Atlas uses automated extraction to summarize mining announcements, identify reported measurements, and classify supporting evidence. Sentiment reflects the extracted narrative and classification rules; it is an interpretation, not a reported measurement. Evidence quotes and context are provided where available. Missing data, low-confidence results, and review flags indicate limitations. Check the original publisher announcement before relying on an interpretation.