Minera Alamos Announces Positive Pre-Feasibility Study for the Copperstone Gold Project in Arizona
Original announcement by tmx on
- Company
- Minera Alamos Inc.
- Ticker
- MAI
- Exchange
- TSX
- Region
- Arizona
- Primary commodity
- Gold
- Secondary commodities
- None reported
- Document categories
- Resource update, Production, Metallurgy
- Extracted
- 2026-09-14 10:44:55 UTC
Analysis by Minestarters Atlas
Minestarters Atlas analysis
Summary
Minera Alamos announced positive results from a Pre-Feasibility Study for its Copperstone Gold Project in Arizona, highlighting robust economics with an after-tax NPV5% of $374 million and an IRR of 108% at a base case gold price of $3,500/oz. The study outlines a 6.3-year mine life producing 291 koz gold at all-in sustaining costs of $1,314/oz. The company reported a 110% increase in contained gold in Measured & Indicated Resources to 630 koz and maiden Proven & Probable Reserves of 303 koz, leading to a board decision to fast-track construction with initial production anticipated by mid-2027.
Reasoning: The Pre-Feasibility Study for the Copperstone Gold Project demonstrates robust economics, significant resource and reserve growth, low capital requirements, and a clear path to production, leading to a board-approved construction decision that is expected to significantly increase the company's gold output.
Positive factors
- Strong project economics with high NPV and IRR at base case gold price
- Significant increase in contained gold in Measured & Indicated Resources (110% increase)
- Maiden Proven & Probable Reserves established
- Low capital intensity for initial development
- Project is fully permitted for construction
- Board of Directors has approved fast-track construction
- Anticipated production will more than double the company's annual gold production
- High gold recovery rate of 96% from the proposed flowsheet
Negative factors
- Inferred Resources are not included in reserves and do not have demonstrated economic viability
Low confidence — this extraction should be reviewed alongside the original source.
Facts used in scoring: 9
Classification and evidence
Measured Resourcepositive
Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves.
Why it applies: The document reports a 'Measured' mineral resource category with specific tonnage and grade.
Evidence · table
“Measured”
Context: Measured
Indicated Resourcepositive
Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.
Why it applies: The document reports an 'Indicated' mineral resource category with specific tonnage and grade.
Evidence · table
“Indicated”
Context: Indicated
Proven Reservepositive
Measured Resource with demonstrated economic viability after applying modifying factors.
Why it applies: The document reports a 'Proven' mineral reserve category with specific tonnage and grade.
Evidence · table
“Proven”
Context: Proven
Probable Reservepositive
Indicated Resource with demonstrated economic viability after applying modifying factors.
Why it applies: The document reports a 'Probable' mineral reserve category with specific tonnage and grade.
Evidence · table
“Probable”
Context: Probable
Category Upgradepositive
Resource confidence improved — Inferred upgraded to Indicated, or Indicated to Measured. De-risking signal.
Why it applies: The document states a '110% increase in contained gold ounces compared to the previous mineral resource estimate' and reports maiden Proven & Probable Reserves, indicating an upgrade in resource confidence and conversion to reserves.
Evidence · text
“representing a 110% increase in contained gold ounces compared to the previous mineral resource estimate. Maiden Proven & Probable Reserves are 1,934 kt grading 4.87 g/t and containing 303 koz gold.”
Contained Metal Growthpositive
True scale improvement — contained metal ounces/tonnes increased vs prior, accounting for both tonnage and grade changes.
Why it applies: The document explicitly states a '110% increase in contained gold ounces compared to the previous mineral resource estimate'.
Evidence · text
“representing a 110% increase in contained gold ounces compared to the previous mineral resource estimate.”
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: The news release states that Darren Koningen, Peter Szkilnyk, Scott Zelligan, Garth Wilcox, Lawrence Segerstrom, and Alex Duggan are Qualified Persons who reviewed and approved the scientific and technical information.
Evidence · text
“The scientific and technical information contained in this news release has been reviewed and approved by Darren Koningen, P.Eng., President and COO of the Company, who is a "Qualified Person" ("QP") as defined under National Instrument 43-101 - Standards of Disclosure for Mineral Projects ("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 mineral resource and reserve estimates explicitly state an underground mining cut-off of 0.064 oz/ton gold (2.2 g/t Au).
Evidence · text
“The MRE is reported at an underground mining cut-off of 0.064 oz/ton gold (2.2 g/t Au).”
NI 43-101 Compliantpositive
Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.
Why it applies: The PFS and associated mineral resource and reserve estimates are prepared in accordance with National Instrument 43-101.
Evidence · text
“A technical report for the Copperstone PFS is being prepared in accordance with National Instrument 43-101 ("NI 43-101")”
Maiden Reservepositive · Story-specific tag
No canonical definition is currently available.
Why it applies: The document explicitly states 'Maiden Proven & Probable Reserves are 1,934 kt grading 4.87 g/t and containing 303 koz gold'.
Evidence · text
“Maiden Proven & Probable Reserves are 1,934 kt grading 4.87 g/t and containing 303 koz gold.”
Resource Updateneutral
Revised estimate for an existing resource — compare to prior to assess progress.
Why it applies: The document presents an 'Updated Mineral Resource Estimate' for the Copperstone project.
Evidence · text
“Updated Mineral Resource Estimate”
PFS-Supportingneutral
Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component.
Why it applies: The entire document is an announcement of a Pre-Feasibility Study (PFS) for the project.
Evidence · text
“Minera Alamos Announces Positive Pre-Feasibility Study for the Copperstone Gold Project in Arizona”
High Recoverypositive
Recovery at or above the exceptional band for the commodity and processing route.
Why it applies: The projected gold recovery of 96% is at the exceptional band for a mill/CIL processing route for gold.
Evidence · text
“projected overall gold recovery of approximately 96%”
Pilot Scale Completepositive
Pilot or demonstration plant testing completed under continuous operation.
Why it applies: The 'Process Plant Design' section describes a flowsheet and plant design, implying detailed testwork beyond bench scale, consistent with a PFS level of study.
Evidence · text
“The proposed flowsheet will incorporate crushing, grinding, flotation, and cyanide leaching circuits to produce a gold concentrate and gold-loaded carbon products.”
Underground Miningneutral · Story-specific tag
No canonical definition is currently available.
Why it applies: The PFS is for an 'underground gold mining project' and discusses underground mining methods.
Evidence · text
“The Copperstone PFS results show a high-return, low capital underground gold mining project”
Low Capital Intensitypositive · Story-specific tag
Below the benchmark for its project type.
Why it applies: The PFS highlights 'Low capital intensity : Total initial capital cost ("capex") of $58 M'.
Evidence · text
“Low capital intensity : Total initial capital cost ("capex") of $58 M”
Fully Permittedpositive · Story-specific tag
Key permits granted with no unresolved challenge.
Why it applies: The document states that the project is 'Fully permitted for construction' and has 'active mining and environmental permits'.
Evidence · text
“Fully permitted for construction : Copperstone is a previously mined property with active mining and environmental permits.”
Inferred Resourcenegative
Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.
Why it applies: The document reports an 'Inferred' mineral resource category, which is a speculative category with limited drilling.
Evidence · table
“Inferred”
Context: Inferred
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 flotation route ("flotation")
Gravity Routeneutral
Gravity separation forms a material part of the flowsheet.
Why it applies: the document describes a gravity route ("gravity")
Extracted facts
Stored fact records: 9. Some facts used in scoring do not have a stored record.
Resource Estimates (8)
measuredCopperstone · goldTonnes: 2198000Grade: 5.08Grade Unit: g/tContained Metal: 359Contained Unit: koz auView all detailsHide details
Identity
- Project
- Copperstone
- Commodity
- gold
- Region
- usa_az
- Reported Region
- Arizona
- Ticker
- MAI
Resource scope
- Estimate type
- resource
- Effective date
- 2025-12-01T00:00:00.000Z
- Reporting standards
- ni_43_101
- QP Signed
- Yes
- Qualified person names
- Darren Koningen, Peter Szkilnyk, Scott Zelligan, Garth Wilcox, Lawrence Segerstrom, Alex Duggan
- Resource group id
- resource:50a5b6fffb126c8302c4
- Mining method
- combined
- Ownership percent
- 100 %
Resource Data
- Category
- measured
- Tonnes
- 2198000
- Grade
- 5.08
- Grade Unit
- g/t
- Contained Metal
- 359
- Contained Unit
- koz au
- Cutoff Grade
- 2.2
- Cutoff Unit
- g/t Au
Prior Estimate
- Resource Date
- 2025-12-01
Review
- Needs Review
- No
- Historical
- No
Dates
- Event date
- 2026-05-27T00:00:00.000Z
Reasoning: The Measured Resource provides a high-confidence base for the project, with a strong grade and substantial contained gold, supporting the positive PFS results.
Positive factors
- High confidence Measured Resource category
- High grade for an underground gold project
- Contributes to significant overall resource growth
Evidence · table
“2,198”
Context: Measured
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
Resource Updateneutral
Revised estimate for an existing resource — compare to prior to assess progress.
Why it applies: the release compares against a previous estimate
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
DFS-Supportingneutral
Resource estimate prepared to support a Definitive Feasibility Study — requires high M&I confidence.
Why it applies: the release names the study this estimate supports
indicatedCopperstone · goldTonnes: 1856000Grade: 4.54Grade Unit: g/tContained Metal: 271Contained Unit: koz auView all detailsHide details
Identity
- Project
- Copperstone
- Commodity
- gold
- Region
- usa_az
- Reported Region
- Arizona
- Ticker
- MAI
Resource scope
- Estimate type
- resource
- Effective date
- 2025-12-01T00:00:00.000Z
- Reporting standards
- ni_43_101
- QP Signed
- Yes
- Qualified person names
- Darren Koningen, Peter Szkilnyk, Scott Zelligan, Garth Wilcox, Lawrence Segerstrom, Alex Duggan
- Resource group id
- resource:8c24500250375a62692f
- Mining method
- combined
- Ownership percent
- 100 %
Resource Data
- Category
- indicated
- Tonnes
- 1856000
- Grade
- 4.54
- Grade Unit
- g/t
- Contained Metal
- 271
- Contained Unit
- koz au
- Cutoff Grade
- 2.2
- Cutoff Unit
- g/t Au
Prior Estimate
- Resource Date
- 2025-12-01
Review
- Needs Review
- No
- Historical
- No
Dates
- Event date
- 2026-05-27T00:00:00.000Z
Reasoning: The Indicated Resource adds substantial tonnage and contained gold with good confidence, supporting the project's economic viability.
Positive factors
- Indicated Resource category provides good geological confidence
- Strong grade for an underground gold project
- Contributes to significant overall resource growth
Evidence · table
“1,856”
Context: Indicated
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
Resource Updateneutral
Revised estimate for an existing resource — compare to prior to assess progress.
Why it applies: the release compares against a previous estimate
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
DFS-Supportingneutral
Resource estimate prepared to support a Definitive Feasibility Study — requires high M&I confidence.
Why it applies: the release names the study this estimate supports
indicatedCopperstone · goldTonnes: 4054000Grade: 4.83Grade Unit: g/tContained Metal: 630Contained Unit: koz auView all detailsHide details
Identity
- Project
- Copperstone
- Commodity
- gold
- Region
- usa_az
- Reported Region
- Arizona
- Ticker
- MAI
Resource scope
- Estimate type
- resource
- Effective date
- 2025-12-01T00:00:00.000Z
- Reporting standards
- ni_43_101
- QP Signed
- Yes
- Qualified person names
- Darren Koningen, Peter Szkilnyk, Scott Zelligan, Garth Wilcox, Lawrence Segerstrom, Alex Duggan
- Resource group id
- resource:55c8c78b2d767223b602
- Mining method
- combined
- Ownership percent
- 100 %
Resource Data
- Category
- indicated
- Tonnes
- 4054000
- Grade
- 4.83
- Grade Unit
- g/t
- Contained Metal
- 630
- Contained Unit
- koz au
- Cutoff Grade
- 2.2
- Cutoff Unit
- g/t Au
Prior Estimate
- Resource Date
- 2025-12-01
Review
- Needs Review
- No
- Historical
- No
Dates
- Event date
- 2026-05-27T00:00:00.000Z
Reasoning: The significant increase in total Measured & Indicated Resources, coupled with a strong average grade, substantially de-risks the project and underpins the positive PFS.
Positive factors
- Total Measured & Indicated Resources show a 110% increase in contained gold ounces compared to previous estimate
- High confidence resource base for economic studies
- Strong average grade for an underground gold project
Evidence · table
“4,054”
Context: Total Measured & Indicated
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
Resource Updateneutral
Revised estimate for an existing resource — compare to prior to assess progress.
Why it applies: the release compares against a previous estimate
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
DFS-Supportingneutral
Resource estimate prepared to support a Definitive Feasibility Study — requires high M&I confidence.
Why it applies: the release names the study this estimate supports
inferredCopperstone · goldTonnes: 401000Grade: 4.04Grade Unit: g/tContained Metal: 52Contained Unit: koz auView all detailsHide details
Identity
- Project
- Copperstone
- Commodity
- gold
- Region
- usa_az
- Reported Region
- Arizona
- Ticker
- MAI
Resource scope
- Estimate type
- resource
- Effective date
- 2025-12-01T00:00:00.000Z
- Reporting standards
- ni_43_101
- QP Signed
- Yes
- Qualified person names
- Darren Koningen, Peter Szkilnyk, Scott Zelligan, Garth Wilcox, Lawrence Segerstrom, Alex Duggan
- Resource group id
- resource:3e07ae74d3be1d447536
- Mining method
- combined
- Ownership percent
- 100 %
Resource Data
- Category
- inferred
- Tonnes
- 401000
- Grade
- 4.04
- Grade Unit
- g/t
- Contained Metal
- 52
- Contained Unit
- koz au
- Cutoff Grade
- 2.2
- Cutoff Unit
- g/t Au
Prior Estimate
- Resource Date
- 2025-12-01
Review
- Needs Review
- No
- Historical
- No
Dates
- Event date
- 2026-05-27T00:00:00.000Z
Reasoning: The Inferred Resource provides future exploration upside but currently has limited economic certainty, as it is not included in reserves.
Positive factors
- Adds to the overall resource base
- Potential for future conversion to higher confidence categories
Negative factors
- Inferred category has lower geological confidence and cannot support economic studies alone
Evidence · table
“401”
Context: Inferred
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
Resource Updateneutral
Revised estimate for an existing resource — compare to prior to assess progress.
Why it applies: the release compares against a previous estimate
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
DFS-Supportingneutral
Resource estimate prepared to support a Definitive Feasibility Study — requires high M&I confidence.
Why it applies: the release names the study this estimate supports
provenCopperstone · goldTonnes: 1052000Grade: 5.06Grade Unit: g/tContained Metal: 172Contained Unit: koz auView all detailsHide details
Identity
- Project
- Copperstone
- Commodity
- gold
- Region
- usa_az
- Reported Region
- Arizona
- Ticker
- MAI
Resource scope
- Estimate type
- reserve
- Effective date
- 2025-12-01T00:00:00.000Z
- Reporting standards
- ni_43_101
- QP Signed
- Yes
- Qualified person names
- Darren Koningen, Peter Szkilnyk, Scott Zelligan, Garth Wilcox, Lawrence Segerstrom, Alex Duggan
- Resource group id
- resource:0001ea878a63dd18441e
- Mining method
- combined
- Ownership percent
- 100 %
Resource Data
- Category
- proven
- Tonnes
- 1052000
- Grade
- 5.06
- Grade Unit
- g/t
- Contained Metal
- 172
- Contained Unit
- koz au
- Cutoff Grade
- 2.2
- Cutoff Unit
- g/t Au
Prior Estimate
- Resource Date
- 2025-12-01
Review
- Needs Review
- No
- Historical
- No
Dates
- Event date
- 2026-05-27T00:00:00.000Z
Reasoning: The establishment of a maiden Proven Reserve is a significant de-risking event, confirming a substantial portion of the resource as economically extractable with high confidence.
Positive factors
- Maiden Proven Reserve demonstrates high confidence and economic viability
- High grade for an underground gold project
- Forms a strong base for mine planning
Evidence · table
“1,052”
Context: Proven
Tags used in scoring
Proven Reservepositive
Measured Resource with demonstrated economic viability after applying modifying factors.
Why it applies: category is "proven"
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
Resource Updateneutral
Revised estimate for an existing resource — compare to prior to assess progress.
Why it applies: the release compares against a previous estimate
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
DFS-Supportingneutral
Resource estimate prepared to support a Definitive Feasibility Study — requires high M&I confidence.
Why it applies: the release names the study this estimate supports
probableCopperstone · goldTonnes: 882000Grade: 4.61Grade Unit: g/tContained Metal: 131Contained Unit: koz auView all detailsHide details
Identity
- Project
- Copperstone
- Commodity
- gold
- Region
- usa_az
- Reported Region
- Arizona
- Ticker
- MAI
Resource scope
- Estimate type
- reserve
- Effective date
- 2025-12-01T00:00:00.000Z
- Reporting standards
- ni_43_101
- QP Signed
- Yes
- Qualified person names
- Darren Koningen, Peter Szkilnyk, Scott Zelligan, Garth Wilcox, Lawrence Segerstrom, Alex Duggan
- Resource group id
- resource:e5fef91e4db71fbe4b41
- Mining method
- combined
- Ownership percent
- 100 %
Resource Data
- Category
- probable
- Tonnes
- 882000
- Grade
- 4.61
- Grade Unit
- g/t
- Contained Metal
- 131
- Contained Unit
- koz au
- Cutoff Grade
- 2.2
- Cutoff Unit
- g/t Au
Prior Estimate
- Resource Date
- 2025-12-01
Review
- Needs Review
- No
- Historical
- No
Dates
- Event date
- 2026-05-27T00:00:00.000Z
Reasoning: The maiden Probable Reserve adds a significant amount of economically viable gold to the project, supporting the positive PFS outcomes.
Positive factors
- Maiden Probable Reserve demonstrates economic viability
- Strong grade for an underground gold project
- Adds to the overall reserve base for mine planning
Evidence · table
“882”
Context: Probable
Tags used in scoring
Probable Reservepositive
Indicated Resource with demonstrated economic viability after applying modifying factors.
Why it applies: category is "probable"
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
Resource Updateneutral
Revised estimate for an existing resource — compare to prior to assess progress.
Why it applies: the release compares against a previous estimate
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
DFS-Supportingneutral
Resource estimate prepared to support a Definitive Feasibility Study — requires high M&I confidence.
Why it applies: the release names the study this estimate supports
probableCopperstone · goldTonnes: 1934000Grade: 4.87Grade Unit: g/tContained Metal: 303Contained Unit: koz auView all detailsHide details
Identity
- Project
- Copperstone
- Commodity
- gold
- Region
- usa_az
- Reported Region
- Arizona
- Ticker
- MAI
Resource scope
- Estimate type
- reserve
- Effective date
- 2025-12-01T00:00:00.000Z
- Reporting standards
- ni_43_101
- QP Signed
- Yes
- Qualified person names
- Darren Koningen, Peter Szkilnyk, Scott Zelligan, Garth Wilcox, Lawrence Segerstrom, Alex Duggan
- Resource group id
- resource:834a6772dce1cb0dc894
- Mining method
- combined
- Ownership percent
- 100 %
Resource Data
- Category
- probable
- Tonnes
- 1934000
- Grade
- 4.87
- Grade Unit
- g/t
- Contained Metal
- 303
- Contained Unit
- koz au
- Cutoff Grade
- 2.2
- Cutoff Unit
- g/t Au
Prior Estimate
- Resource Date
- 2025-12-01
Review
- Needs Review
- No
- Historical
- No
Dates
- Event date
- 2026-05-27T00:00:00.000Z
Reasoning: The establishment of maiden Proven & Probable Reserves is a key milestone, confirming the economic viability of a substantial portion of the resource and enabling the construction decision.
Positive factors
- Maiden Total Proven & Probable Reserves provide a robust economic foundation for the project
- Strong average grade for an underground gold project
- Supports the positive PFS and construction decision
Evidence · table
“1,934”
Context: Total Proven & Probable
Tags used in scoring
Probable Reservepositive
Indicated Resource with demonstrated economic viability after applying modifying factors.
Why it applies: category is "probable"
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
Resource Updateneutral
Revised estimate for an existing resource — compare to prior to assess progress.
Why it applies: the release compares against a previous estimate
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
DFS-Supportingneutral
Resource estimate prepared to support a Definitive Feasibility Study — requires high M&I confidence.
Why it applies: the release names the study this estimate supports
Fact 8Copperstone · goldView all detailsHide details
Identity
- Project
- Copperstone
- Commodity
- gold
- Region
- usa_az
- Reported Region
- Arizona
- Ticker
- MAI
Resource scope
- Effective date
- 2025-12-01T00:00:00.000Z
- Reporting standards
- ni_43_101
- Resource group id
- resource:d9b54984c3e2732e06f2
- Mining method
- combined
- Ownership percent
- 100 %
Review
- Needs Review
- No
- Historical
- No
Dates
- Event date
- 2026-05-27T00:00:00.000Z
Reasoning: The production profile demonstrates a low-cost, high-return operation with a substantial mine life and significant contribution to the company's overall gold production, justifying the construction decision.
Positive factors
- Robust mine life of 6.3 years with significant total gold production
- Low all-in sustaining costs ($1,314/oz) and cash operating costs ($1,070/oz)
- Low initial capital intensity ($58.3M)
- Average annual production of 46 koz gold will more than double company's current production
Evidence · text
“PFS life-of-mine ("LOM") plan shows an initial 6.3-year mine life producing a total of 291 koz gold with average annual production of 46 koz at total cash costs 1 of $1,070/oz gold and all-in sustaining costs 1 ("AISC") of $1,314/oz gold.”
Tags used in scoring
Cut-off Undisclosednegative
High-grade interval reported without stating the cut-off grade used for compositing.
Why it applies: no cutoff_grade was stated
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
No Contained Metalnegative
Tonnage and grade reported but contained metal not calculated or disclosed — incomplete reporting.
Why it applies: contained_metal was not reported
Resource Updateneutral
Revised estimate for an existing resource — compare to prior to assess progress.
Why it applies: the release compares against a previous estimate
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
DFS-Supportingneutral
Resource estimate prepared to support a Definitive Feasibility Study — requires high M&I confidence.
Why it applies: the release names the study this estimate supports
Metallurgical Results (1)
mill routeCopperstone · goldRecovery: 96 %View all detailsHide details
Identity
- Project
- Copperstone
- Commodity
- gold
- Region
- usa_az
- Reported Region
- Arizona
- Ticker
- MAI
Test Work
- Program Status
- detailed
- Test Type
- mill route
- Processing Route
- crushing, grinding, flotation, and cyanide leaching circuits
Recovery
- Recovery
- 96 %
- Recovery Basis
- actual_test
Review
- Needs Review
- No
- Historical
- No
Dates
- Event date
- 2026-05-27T00:00:00.000Z
Reasoning: The high gold recovery rate of 96% is a significant positive for the project's economics, indicating efficient processing of the ore.
Positive factors
- Exceptional gold recovery rate of 96%
- Hybrid process designed for flexibility and high recoveries
- Supports strong project economics
Evidence · text
“projected overall gold recovery of approximately 96%”
Tags used in scoring
Mill Routeneutral
Processing via mill or concentrator (CIL, CIP, tank leach, flotation).
Why it applies: processing_route matches the mill_cil signal
High Recoverypositive
Recovery at or above the exceptional band for the commodity and processing route.
Why it applies: 96% is at or above the exceptional band (95%)
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.