Lion Copper and Gold Corp. Announces Positive Pea Results for Its Yerington, Nevada Copper Project That Includes the Use of Rio Tinto's Nuton Technologies

Original announcement by tmx on

Company
Lion Copper and Gold Corp.
Ticker
LEO
Exchange
TSX
Region
Nevada
Primary commodity
Copper
Secondary commodities
None reported
Document categories
Resource update, Economic study, Metallurgy
Extracted
2026-09-18 07:14:24 UTC

Analysis by Minestarters Atlas

Minestarters Atlas analysis

Summary

Lion Copper and Gold Corp. announced positive Preliminary Economic Assessment (PEA) results for its Yerington Copper Project in Nevada, featuring a post-tax NPV7% of US$356 million and an IRR of 17.4% at a copper price of $3.85/lb. The PEA outlines a 12-year open pit mine life utilizing Rio Tinto's Nuton technologies for processing primary sulfide copper, eliminating the need for a concentrator and tailings impoundment. The release also includes updated mineral resource estimates for the Yerington Deposit, W-3 Stockpile, and VLT, alongside historical estimates for the MacArthur Deposit.

Reasoning: The document announces positive PEA results for the Yerington Copper Project, highlighting strong economics and the use of innovative Nuton technologies for sulfide processing. It also provides updated mineral resource estimates for Yerington, W-3 Stockpile, and VLT, along with historical estimates for MacArthur, and detailed metallurgical recovery projections. The PEA's preliminary nature and reliance on inferred resources are noted.

Positive factors

  • Positive PEA results with strong post-tax IRR and NPV
  • Utilization of innovative Nuton technologies for sulfide processing, eliminating concentrator and tailings
  • Low overall open pit strip ratio
  • Significant contained copper in resource estimates across multiple deposits
  • High copper recoveries projected for both oxide and sulfide materials

Negative factors

  • PEA is preliminary in nature and includes inferred mineral resources
  • MacArthur resource estimate is historical and not updated in this release
  • No explicit disclosure of the PEA's effective base date, only the publication date

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

Facts used in scoring: 32

Classification and evidence

PEA Onlyneutral

Only Class 4 / Initial Assessment economics available. Not bankable.

Why it applies: The economic assessment is explicitly stated as a Preliminary Economic Assessment (PEA).

Evidence · text

“Preliminary Economic Assessment (" PEA ")”

Inferred Heavy Feednegative

Material Inferred share of LOM mill feed, or the share is undisclosed.

Why it applies: The PEA explicitly states it 'includes inferred mineral resources that are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves'.

Evidence · text

“The PEA is preliminary in nature, includes inferred mineral resources that are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves”

High IRRpositive

Post-tax real unlevered IRR in the strong tier or better.

Why it applies: The post-tax IRR of 17.4% is in the strong tier for economic studies.

Evidence · table

“17.4”

Context: IRR

Fast Paybackpositive

Payback in the strong tier or better, on the required basis.

Why it applies: The post-tax payback period of 5.0 years is in the moderate tier.

Evidence · table

“5.0”

Context: Payback Period

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: Multiple Qualified Persons are named as responsible for the PEA Technical Report and have reviewed the news release.

Evidence · text

“The Qualified Persons (QPs), as that term is defined in NI 43-101, responsible for the preparation of the PEA Technical Report, include: Gordon Zurowski, P.Eng., Principal Mine Engineer (AGP Mining Consultants Inc.) Tim Maunula, P.Geo, Principal Resource Geologist (T. Maunula & Associates Consulting Inc.) - Yerington Mineral Resource estimate Herb Welhener, MMSA-QPM, Vice President (Independent Mining Consultants, Inc.) - MacArthur Mineral Resource estimate Adrien Butler, P.E., Senior Civil Engineer (NewFields) Jeff Woods, QP, Principal Process Engineer (Woods Process Services, LLC)”

NI 43-101 Compliantpositive

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

Why it applies: The PEA was prepared in accordance with Canadian National Instrument 43-101.

Evidence · text

“prepared in accordance with the requirements set forth by Canadian National Instrument 43-101 (" NI 43-101 ")”

High Recoverypositive

Recovery at or above the exceptional band for the commodity and processing route.

Why it applies: The projected copper recovery for Yerington Sulfide-Nuton is 74%, which is strong for a heap leach process.

Evidence · table

“74%”

Context: Yerington Sulfide-Nuton

Pilot Scale Completepositive

Pilot or demonstration plant testing completed under continuous operation.

Why it applies: The Nuton technologies are described as a 'proprietary catalytic bio-heap leaching innovation' and are being evaluated, with further testing slated to confirm metallurgical performance.

Evidence · text

“Nuton technologies are being evaluated to enable the unlocking of primary sulfide copper resources in a more cost-efficient, environmentally friendly manner, and affording the unique opportunity to produce copper cathode on-site for domestic consumption. ... Further testing of Nuton technologies is slated to confirm metallurgical performance through replicate trials, with completion anticipated in 2024.”

Resource Updateneutral

Revised estimate for an existing resource — compare to prior to assess progress.

Why it applies: The document provides updated mineral resource estimates for the Yerington Deposit, W-3 Stockpile, and VLT.

Evidence · text

“The updated Mineral Resources for the Yerington Deposit are: Measured Resources of 62.9 Mtons at 0.30% TCu; Indicated Resources of 94.7 Mtons at 0.27% TCu; and Inferred Resources of 113.2 Mtons at 0.22% TCu (Table 6).”

Stale Estimatenegative

Effective date is >2 years old — data currency concern, may not reflect current geological understanding.

Why it applies: The MacArthur Mineral Resource estimate has an effective date of February 25, 2022, which is more than two years old.

Evidence · text

“The effective date of the MacArthur Mineral Resource estimate is February 25, 2022.”

Cut-off Disclosedpositive

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

Why it applies: A current resource fact retains the disclosed cut-off grade

Heap Leach Routeneutral

Processing via heap leach — lower CAPEX and OPEX, lower recovery expected.

Why it applies: the document describes a heap_leach route ("heap leach")

Mill Routeneutral

Processing via mill or concentrator (CIL, CIP, tank leach, flotation).

Why it applies: the document describes a mill_cil route ("concentrator")

Multi-Domain Testedpositive

Variability across ore domains (oxide, transition, fresh) has been addressed.

Why it applies: 6 distinct composites were tested

Extracted facts

Stored fact records: 30. Some facts used in scoring do not have a stored record.

Resource Estimates (23)

measuredYerington Deposit · copperTonnes: 20230000Grade: 0.25Grade Unit: %Contained Metal: 99367000Contained Unit: lbsView all details
Link to this fact

Identity

Project
Yerington Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-05-01T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:abf7f940c3ebc3c967fe
Deposit or zone
Yerington Deposit
Material type
oxide

Resource Data

Category
measured
Tonnes
20230000
Grade
0.25
Grade Unit
%
Contained Metal
99367000
Contained Unit
lbs
Cutoff Grade
0.038
Cutoff Unit
%

Prior Estimate

Resource Date
2023-05-01

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Measured Oxide resource of 20.23 Mtons at 0.25% TCu represents a high-confidence portion of the Yerington Deposit, contributing significantly to the project's overall resource base.

Positive factors

  • Measured category indicates high confidence
  • Good contained copper for oxide material

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

measuredYerington Deposit · copperTonnes: 42671000Grade: 0.32Grade Unit: %Contained Metal: 274578000Contained Unit: lbsView all details
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Identity

Project
Yerington Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-05-01T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:f847c01eae7601e70bf9
Deposit or zone
Yerington Deposit
Material type
sulphide

Resource Data

Category
measured
Tonnes
42671000
Grade
0.32
Grade Unit
%
Contained Metal
274578000
Contained Unit
lbs
Cutoff Grade
0.126
Cutoff Unit
%

Prior Estimate

Resource Date
2023-05-01

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Measured Sulfide resource of 42.67 Mtons at 0.32% TCu is a significant, high-confidence component of the Yerington Deposit, especially given the planned Nuton processing for sulfides.

Positive factors

  • Measured category indicates high confidence
  • Higher grade and contained copper for sulfide material

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

measuredYerington Deposit · copperTonnes: 62901000Grade: 0.3Grade Unit: %Contained Metal: 373945000Contained Unit: lbsView all details
Link to this fact

Identity

Project
Yerington Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-05-01T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:8a314529cdea6bfb521b
Deposit or zone
Yerington Deposit

Resource Data

Category
measured
Tonnes
62901000
Grade
0.3
Grade Unit
%
Contained Metal
373945000
Contained Unit
lbs

Prior Estimate

Resource Date
2023-05-01

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The total Measured resource of 62.9 Mtons at 0.30% TCu provides a solid, high-confidence foundation for the Yerington project.

Positive factors

  • Large Measured resource base for the Yerington Deposit
  • High confidence in the resource estimate

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 Undisclosednegative

High-grade interval reported without stating the cut-off grade used for compositing.

Why it applies: no cutoff_grade was 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

indicatedYerington Deposit · copperTonnes: 13749000Grade: 0.22Grade Unit: %Contained Metal: 60166000Contained Unit: lbsView all details
Link to this fact

Identity

Project
Yerington Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-05-01T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:5162107302d3e5969ecb
Deposit or zone
Yerington Deposit
Material type
oxide

Resource Data

Category
indicated
Tonnes
13749000
Grade
0.22
Grade Unit
%
Contained Metal
60166000
Contained Unit
lbs
Cutoff Grade
0.038
Cutoff Unit
%

Prior Estimate

Resource Date
2023-05-01

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Indicated Oxide resource of 13.75 Mtons at 0.22% TCu adds to the project's resource base with reasonable confidence, supporting future economic studies.

Positive factors

  • Indicated category provides reasonable geological confidence

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

indicatedYerington Deposit · copperTonnes: 80960000Grade: 0.28Grade Unit: %Contained Metal: 457921000Contained Unit: lbsView all details
Link to this fact

Identity

Project
Yerington Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-05-01T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:21e1fefb808637761ce2
Deposit or zone
Yerington Deposit
Material type
sulphide

Resource Data

Category
indicated
Tonnes
80960000
Grade
0.28
Grade Unit
%
Contained Metal
457921000
Contained Unit
lbs
Cutoff Grade
0.126
Cutoff Unit
%

Prior Estimate

Resource Date
2023-05-01

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Indicated Sulfide resource of 80.96 Mtons at 0.28% TCu is a substantial component, providing reasonable confidence for future mine planning, especially with the Nuton technology.

Positive factors

  • Large Indicated Sulfide resource
  • Reasonable geological confidence

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

indicatedYerington Deposit · copperTonnes: 94709000Grade: 0.27Grade Unit: %Contained Metal: 518087000Contained Unit: lbsView all details
Link to this fact

Identity

Project
Yerington Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-05-01T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:0296152d4d5aa40a0f1b
Deposit or zone
Yerington Deposit

Resource Data

Category
indicated
Tonnes
94709000
Grade
0.27
Grade Unit
%
Contained Metal
518087000
Contained Unit
lbs

Prior Estimate

Resource Date
2023-05-01

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The total Indicated resource of 94.71 Mtons at 0.27% TCu significantly contributes to the project's overall resource, providing a good level of confidence for ongoing development.

Positive factors

  • Substantial Indicated resource base for the Yerington Deposit
  • Reasonable confidence for future studies

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 Undisclosednegative

High-grade interval reported without stating the cut-off grade used for compositing.

Why it applies: no cutoff_grade was 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

inferredYerington Deposit · copperTonnes: 33347000Grade: 0.18Grade Unit: %Contained Metal: 122221000Contained Unit: lbsView all details
Link to this fact

Identity

Project
Yerington Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-05-01T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:ba105102cfcbce3b11a4
Deposit or zone
Yerington Deposit
Material type
oxide

Resource Data

Category
inferred
Tonnes
33347000
Grade
0.18
Grade Unit
%
Contained Metal
122221000
Contained Unit
lbs
Cutoff Grade
0.038
Cutoff Unit
%

Prior Estimate

Resource Date
2023-05-01

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Inferred Oxide resource of 33.35 Mtons at 0.18% TCu provides exploration upside but has lower confidence and cannot be used for economic studies alone.

Negative factors

  • Inferred category indicates lower geological confidence

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

inferredYerington Deposit · copperTonnes: 79881000Grade: 0.24Grade Unit: %Contained Metal: 385938000Contained Unit: lbsView all details
Link to this fact

Identity

Project
Yerington Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-05-01T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:d13958ba90c61bb0cb15
Deposit or zone
Yerington Deposit
Material type
sulphide

Resource Data

Category
inferred
Tonnes
79881000
Grade
0.24
Grade Unit
%
Contained Metal
385938000
Contained Unit
lbs
Cutoff Grade
0.126
Cutoff Unit
%

Prior Estimate

Resource Date
2023-05-01

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Inferred Sulfide resource of 79.88 Mtons at 0.24% TCu represents a significant target for future drilling to upgrade its confidence, especially with the Nuton processing technology.

Positive factors

  • Large Inferred Sulfide resource provides future potential

Negative factors

  • Inferred category indicates lower geological confidence

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

inferredYerington Deposit · copperTonnes: 113229000Grade: 0.22Grade Unit: %Contained Metal: 508159000Contained Unit: lbsView all details
Link to this fact

Identity

Project
Yerington Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-05-01T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:4810adf30f584a131393
Deposit or zone
Yerington Deposit

Resource Data

Category
inferred
Tonnes
113229000
Grade
0.22
Grade Unit
%
Contained Metal
508159000
Contained Unit
lbs

Prior Estimate

Resource Date
2023-05-01

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The total Inferred resource of 113.23 Mtons at 0.22% TCu represents a substantial exploration target, but its speculative nature means it cannot be directly incorporated into current economic studies.

Positive factors

  • Significant total Inferred resource for the Yerington Deposit

Negative factors

  • Inferred category limits current economic applicability

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 Undisclosednegative

High-grade interval reported without stating the cut-off grade used for compositing.

Why it applies: no cutoff_grade was 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

inferredW-3 Stockpile · copperTonnes: 14100000Grade: 0.11Grade Unit: %Contained Metal: 30571000Contained Unit: lbsView all details
Link to this fact

Identity

Project
W-3 Stockpile
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-07-31T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:03df0024390684262115
Deposit or zone
W-3 Stockpile
Material type
oxide

Resource Data

Category
inferred
Tonnes
14100000
Grade
0.11
Grade Unit
%
Contained Metal
30571000
Contained Unit
lbs
Cutoff Grade
0.04
Cutoff Unit
%

Prior Estimate

Resource Date
2023-07-31

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Inferred resource in the W-3 Stockpile represents potential value from historical operations, but its low grade and inferred classification mean it requires further evaluation.

Positive factors

  • Identified resource in existing stockpile

Negative factors

  • Inferred category indicates lower confidence
  • Low grade for oxide material

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

inferredVat-Leached Tailings · copperTonnes: 33160000Grade: 0.09Grade Unit: %Contained Metal: 62622000Contained Unit: lbsView all details
Link to this fact

Identity

Project
Vat-Leached Tailings
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2023-07-31T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Tim Maunula
Resource group id
resource:1c28648435fde7a91ef9
Deposit or zone
Vat-Leached Tailings
Material type
oxide

Resource Data

Category
inferred
Tonnes
33160000
Grade
0.09
Grade Unit
%
Contained Metal
62622000
Contained Unit
lbs
Cutoff Grade
0.04
Cutoff Unit
%

Prior Estimate

Resource Date
2023-07-31

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Inferred resource in the Vat-Leached Tailings represents potential value from historical processing, but its very low grade and inferred classification require significant de-risking.

Positive factors

  • Identified resource in existing tailings

Negative factors

  • Inferred category indicates lower confidence
  • Very low grade for oxide material

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

measuredMacArthur Deposit · copperTonnes: 116666000Grade: 0.18Grade Unit: %Contained Metal: 420929000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:1b70c3932e75b9dba38a
Deposit or zone
MacArthur Deposit

Resource Data

Category
measured
Tonnes
116666000
Grade
0.18
Grade Unit
%
Contained Metal
420929000
Contained Unit
lbs

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Measured resource of 116.67 Mtons at 0.18% TCu for MacArthur is substantial but is historical, reducing its novelty and requiring an update for current project evaluation.

Positive factors

  • Large Measured resource base for MacArthur Deposit

Negative factors

  • Estimate is historical, effective date is over two years old

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 Undisclosednegative

High-grade interval reported without stating the cut-off grade used for compositing.

Why it applies: no cutoff_grade was 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

indicatedMacArthur Deposit · copperTonnes: 183665000Grade: 0.158Grade Unit: %Contained Metal: 579479000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:a0206d0890bf76690694
Deposit or zone
MacArthur Deposit

Resource Data

Category
indicated
Tonnes
183665000
Grade
0.158
Grade Unit
%
Contained Metal
579479000
Contained Unit
lbs

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Indicated resource of 183.67 Mtons at 0.158% TCu for MacArthur is substantial but is historical, reducing its novelty and requiring an update for current project evaluation.

Positive factors

  • Large Indicated resource base for MacArthur Deposit

Negative factors

  • Estimate is historical, effective date is over two years old

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 Undisclosednegative

High-grade interval reported without stating the cut-off grade used for compositing.

Why it applies: no cutoff_grade was 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

inferredMacArthur Deposit · copperTonnes: 156450000Grade: 0.151Grade Unit: %Contained Metal: 471714000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:3a7c3d15fa437600ff62
Deposit or zone
MacArthur Deposit

Resource Data

Category
inferred
Tonnes
156450000
Grade
0.151
Grade Unit
%
Contained Metal
471714000
Contained Unit
lbs

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Inferred resource of 156.45 Mtons at 0.151% TCu for MacArthur is a large exploration target, but its historical nature and inferred classification reduce its current utility for economic studies.

Positive factors

  • Significant Inferred resource base for MacArthur Deposit

Negative factors

  • Estimate is historical, effective date is over two years old
  • Inferred category indicates lower confidence

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 Undisclosednegative

High-grade interval reported without stating the cut-off grade used for compositing.

Why it applies: no cutoff_grade was 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

measuredMacArthur Deposit · copperTonnes: 82983000Grade: 0.184Grade Unit: %Contained Metal: 305303000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:4e0ceb0065649646e4b8
Deposit or zone
MacArthur

Resource Data

Category
measured
Tonnes
82983000
Grade
0.184
Grade Unit
%
Contained Metal
305303000
Contained Unit
lbs
Cutoff Grade
0.06
Cutoff Unit
%

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Measured resource for the MacArthur domain is a significant, high-confidence component, but its historical nature means it needs to be updated for current project planning.

Positive factors

  • Large Measured resource for the MacArthur domain

Negative factors

  • Estimate is historical, effective date is over two years old

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

measuredMacArthur Deposit · copperTonnes: 25149000Grade: 0.176Grade Unit: %Contained Metal: 88507000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:950195ca39912fca10c8
Deposit or zone
North Ridge

Resource Data

Category
measured
Tonnes
25149000
Grade
0.176
Grade Unit
%
Contained Metal
88507000
Contained Unit
lbs
Cutoff Grade
0.06
Cutoff Unit
%

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Measured resource for the North Ridge domain is a high-confidence component, but its historical nature means it needs to be updated for current project planning.

Positive factors

  • Measured resource for the North Ridge domain

Negative factors

  • Estimate is historical, effective date is over two years old

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

measuredMacArthur Deposit · copperTonnes: 8534000Grade: 0.159Grade Unit: %Contained Metal: 27119000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:4dd114fb4af5f4e2d5a5
Deposit or zone
Gallagher

Resource Data

Category
measured
Tonnes
8534000
Grade
0.159
Grade Unit
%
Contained Metal
27119000
Contained Unit
lbs
Cutoff Grade
0.06
Cutoff Unit
%

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Measured resource for the Gallagher domain is a high-confidence component, but its historical nature means it needs to be updated for current project planning.

Positive factors

  • Measured resource for the Gallagher domain

Negative factors

  • Estimate is historical, effective date is over two years old

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

indicatedMacArthur Deposit · copperTonnes: 77171000Grade: 0.151Grade Unit: %Contained Metal: 233446000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:4aaffcbd4a5755a82b31
Deposit or zone
MacArthur

Resource Data

Category
indicated
Tonnes
77171000
Grade
0.151
Grade Unit
%
Contained Metal
233446000
Contained Unit
lbs
Cutoff Grade
0.06
Cutoff Unit
%

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Indicated resource for the MacArthur domain is a significant component, but its historical nature means it needs to be updated for current project planning.

Positive factors

  • Large Indicated resource for the MacArthur domain

Negative factors

  • Estimate is historical, effective date is over two years old

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

indicatedMacArthur Deposit · copperTonnes: 78305000Grade: 0.166Grade Unit: %Contained Metal: 259558000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:cdf01abd78a7143fe7d0
Deposit or zone
North Ridge

Resource Data

Category
indicated
Tonnes
78305000
Grade
0.166
Grade Unit
%
Contained Metal
259558000
Contained Unit
lbs
Cutoff Grade
0.06
Cutoff Unit
%

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Indicated resource for the North Ridge domain is a significant component, but its historical nature means it needs to be updated for current project planning.

Positive factors

  • Large Indicated resource for the North Ridge domain

Negative factors

  • Estimate is historical, effective date is over two years old

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

indicatedMacArthur Deposit · copperTonnes: 28189000Grade: 0.153Grade Unit: %Contained Metal: 86475000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:374381f03c7d2a858a2b
Deposit or zone
Gallagher

Resource Data

Category
indicated
Tonnes
28189000
Grade
0.153
Grade Unit
%
Contained Metal
86475000
Contained Unit
lbs
Cutoff Grade
0.06
Cutoff Unit
%

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Indicated resource for the Gallagher domain is a component of the overall resource, but its historical nature means it needs to be updated for current project planning.

Positive factors

  • Indicated resource for the Gallagher domain

Negative factors

  • Estimate is historical, effective date is over two years old

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

inferredMacArthur Deposit · copperTonnes: 30815000Grade: 0.158Grade Unit: %Contained Metal: 97490000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:13a8b623b0f40ca6b3f1
Deposit or zone
MacArthur

Resource Data

Category
inferred
Tonnes
30815000
Grade
0.158
Grade Unit
%
Contained Metal
97490000
Contained Unit
lbs
Cutoff Grade
0.06
Cutoff Unit
%

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Inferred resource for the MacArthur domain is a significant target, but its historical nature and inferred classification reduce its current utility for economic studies.

Positive factors

  • Inferred resource for the MacArthur domain

Negative factors

  • Estimate is historical, effective date is over two years old
  • Inferred category indicates lower confidence

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

inferredMacArthur Deposit · copperTonnes: 62593000Grade: 0.154Grade Unit: %Contained Metal: 192187000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:f1058330e8ab94caf68a
Deposit or zone
North Ridge

Resource Data

Category
inferred
Tonnes
62593000
Grade
0.154
Grade Unit
%
Contained Metal
192187000
Contained Unit
lbs
Cutoff Grade
0.06
Cutoff Unit
%

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Inferred resource for the North Ridge domain is a significant target, but its historical nature and inferred classification reduce its current utility for economic studies.

Positive factors

  • Large Inferred resource for the North Ridge domain

Negative factors

  • Estimate is historical, effective date is over two years old
  • Inferred category indicates lower confidence

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

inferredMacArthur Deposit · copperTonnes: 63042000Grade: 0.144Grade Unit: %Contained Metal: 182037000Contained Unit: lbsHistorical resultNeeds review: historical_restatementView all details
Link to this fact

Identity

Project
MacArthur Deposit
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Resource scope

Estimate type
resource
Effective date
2022-02-25T00:00:00.000Z
Reporting standards
ni_43_101, sec_sk1300
QP Signed
Yes
Qualified person names
Herb Welhener
Resource group id
resource:9713386636d51af03b94
Deposit or zone
Gallagher

Resource Data

Category
inferred
Tonnes
63042000
Grade
0.144
Grade Unit
%
Contained Metal
182037000
Contained Unit
lbs
Cutoff Grade
0.06
Cutoff Unit
%

Prior Estimate

Resource Date
2022-02-25

Review

Needs Review
Yes
Review Reason
historical_restatement
Historical
Yes
Historical Source Date
2022-02-25T00:00:00.000Z

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: The Inferred resource for the Gallagher domain is a significant target, but its historical nature and inferred classification reduce its current utility for economic studies.

Positive factors

  • Significant Inferred resource for the Gallagher domain

Negative factors

  • Estimate is historical, effective date is over two years old
  • Inferred category indicates lower confidence

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

Metallurgical Results (7)

heap leachYerington Copper Project · copperRecovery: 82 %View all details
Link to this fact

Identity

Project
Yerington Copper Project
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Test Work

Program Status
preliminary
Test Type
heap leach
Processing Route
heap leach
Sample
MacArthur Oxide

Recovery

Recovery
82 %
Recovery Basis
actual_test

Reagents

Reagent Notes
Sized to 6" minus ROM

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: An 82% recovery for MacArthur Oxide material via heap leach is a strong result, indicating efficient extraction for this ore type.

Positive factors

  • High recovery for oxide material via heap leach

Tags used in scoring

Heap Leach Routeneutral

Processing via heap leach — lower CAPEX and OPEX, lower recovery expected.

Why it applies: processing_route matches the heap_leach signal

High Recoverypositive

Recovery at or above the exceptional band for the commodity and processing route.

Why it applies: 82% is at or above the exceptional band (80%)

heap leachYerington Copper Project · copperRecovery: 54 %View all details
Link to this fact

Identity

Project
Yerington Copper Project
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Test Work

Program Status
preliminary
Test Type
heap leach
Processing Route
heap leach
Sample
Gallagher Oxide

Recovery

Recovery
54 %
Recovery Basis
actual_test

Reagents

Reagent Notes
Sized to 6" minus

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: A 54% recovery for Gallagher Oxide material is low for a heap leach process, suggesting potential challenges or lower amenability for this specific domain.

Negative factors

  • Recovery is below the weak band for heap leach oxide copper

Tags used in scoring

Heap Leach Routeneutral

Processing via heap leach — lower CAPEX and OPEX, lower recovery expected.

Why it applies: processing_route matches the heap_leach signal

heap leachYerington Copper Project · copperRecovery: 53 %View all details
Link to this fact

Identity

Project
Yerington Copper Project
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Test Work

Program Status
preliminary
Test Type
heap leach
Processing Route
heap leach
Sample
North Area Oxide

Recovery

Recovery
53 %
Recovery Basis
actual_test

Reagents

Reagent Notes
Sized to 6" minus

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: A 53% recovery for North Area Oxide material is low for a heap leach process, similar to Gallagher, indicating potential processing challenges for this domain.

Negative factors

  • Recovery is below the weak band for heap leach oxide copper

Tags used in scoring

Heap Leach Routeneutral

Processing via heap leach — lower CAPEX and OPEX, lower recovery expected.

Why it applies: processing_route matches the heap_leach signal

heap leachYerington Copper Project · copperRecovery: 70 %View all details
Link to this fact

Identity

Project
Yerington Copper Project
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Test Work

Program Status
preliminary
Test Type
heap leach
Processing Route
heap leach
Sample
Yerington Oxide

Recovery

Recovery
70 %
Recovery Basis
actual_test

Reagents

Reagent Notes
ROM

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: A 70% recovery for Yerington Oxide material via ROM heap leach is a moderate result, indicating reasonable amenability to this processing method.

Positive factors

  • Recovery is within the moderate band for heap leach oxide copper

Tags used in scoring

Heap Leach Routeneutral

Processing via heap leach — lower CAPEX and OPEX, lower recovery expected.

Why it applies: processing_route matches the heap_leach signal

heap leachYerington Copper Project · copperRecovery: 68 %View all details
Link to this fact

Identity

Project
Yerington Copper Project
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Test Work

Program Status
preliminary
Test Type
heap leach
Processing Route
heap leach
Sample
W3 Oxide

Recovery

Recovery
68 %
Recovery Basis
actual_test

Reagents

Reagent Notes
ROM

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: A 68% recovery for W3 Oxide material via ROM heap leach is a moderate result, indicating reasonable amenability to this processing method.

Positive factors

  • Recovery is within the moderate band for heap leach oxide copper

Tags used in scoring

Heap Leach Routeneutral

Processing via heap leach — lower CAPEX and OPEX, lower recovery expected.

Why it applies: processing_route matches the heap_leach signal

heap leachYerington Copper Project · copperRecovery: 75 %View all details
Link to this fact

Identity

Project
Yerington Copper Project
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Test Work

Program Status
preliminary
Test Type
heap leach
Processing Route
heap leach
Sample
VLT Oxide

Recovery

Recovery
75 %
Recovery Basis
actual_test

Reagents

Reagent Notes
ROM

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: A 75% recovery for VLT Oxide material via ROM heap leach is a strong result, indicating good amenability to this processing method.

Positive factors

  • Recovery is strong for heap leach oxide copper

Tags used in scoring

Heap Leach Routeneutral

Processing via heap leach — lower CAPEX and OPEX, lower recovery expected.

Why it applies: processing_route matches the heap_leach signal

heap leachYerington Copper Project · copperRecovery: 74 %View all details
Link to this fact

Identity

Project
Yerington Copper Project
Commodity
copper
Region
usa_nv
Reported Region
Nevada
Ticker
LEO

Test Work

Program Status
preliminary
Test Type
heap leach
Processing Route
Tertiary Crushed Agglomerated Conveyor Stacked: Nuton Process
Sample
Yerington Sulfide-Nuton

Recovery

Recovery
74 %
Recovery Basis
actual_test

Review

Needs Review
No
Historical
No

Dates

Event date
2024-01-30T00:00:00.000Z

Reasoning: A 74% recovery for sulfide material using the Nuton process is a strong and novel result, as it enables heap leaching of sulfides, which traditionally require more complex processing. This is a key de-risking factor for the project.

Positive factors

  • Strong recovery for sulfide material using innovative Nuton technology
  • Nuton process eliminates need for concentrator and tailings impoundment

Negative factors

  • Test work remains ongoing and subject to refinement

Tags used in scoring

Heap Leach Routeneutral

Processing via heap leach — lower CAPEX and OPEX, lower recovery expected.

Why it applies: processing_route matches the heap_leach signal

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.