# Minera Alamos Announces Positive Pre-Feasibility Study for the Copperstone Gold Project in Arizona Canonical Atlas analysis: https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720 Original source: https://money.tmx.com/en/quote/MAI/news/7839448542604975/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold- Publisher: tmx Original announcement: 2026-05-27T21:00:00.000Z Analysis by Minestarters Atlas Atlas analysis published: Unknown date Atlas analysis updated: Unknown date - 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 Narrative sentiment: 0.90 · Bullish ## Minestarters Atlas 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 factor: Strong project economics with high NPV and IRR at base case gold price - Positive factor: Significant increase in contained gold in Measured & Indicated Resources \(110% increase\) - Positive factor: Maiden Proven & Probable Reserves established - Positive factor: Low capital intensity for initial development - Positive factor: Project is fully permitted for construction - Positive factor: Board of Directors has approved fast-track construction - Positive factor: Anticipated production will more than double the company's annual gold production - Positive factor: High gold recovery rate of 96% from the proposed flowsheet - Negative factor: 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 Resource** Polarity: positive Definition: 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 Resource** Polarity: positive Definition: 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 Reserve** Polarity: positive Definition: 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 Reserve** Polarity: positive Definition: 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 Upgrade** Polarity: positive Definition: 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 Growth** Polarity: positive Definition: 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 Signed** Polarity: positive Definition: 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 Disclosed** Polarity: positive Definition: 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 Compliant** Polarity: positive Definition: 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 Reserve** Polarity: positive Story-specific tag Definition: 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 Update** Polarity: neutral Definition: 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-Supporting** Polarity: neutral Definition: 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 Recovery** Polarity: positive Definition: 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 Complete** Polarity: positive Definition: 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 Mining** Polarity: neutral Story-specific tag Definition: 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 Intensity** Polarity: positive Story-specific tag Definition: 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 Permitted** Polarity: positive Story-specific tag Definition: 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 Resource** Polarity: negative Definition: 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 Route** Polarity: neutral Definition: Processing via heap leach — lower CAPEX and OPEX, lower recovery expected. Why it applies: the document describes a heap\_leach route \("heap leach"\) **Mill Route** Polarity: neutral Definition: Processing via mill or concentrator \(CIL, CIP, tank leach, flotation\). Why it applies: the document describes a flotation route \("flotation"\) **Gravity Route** Polarity: neutral Definition: 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) ### measured [Link to this fact](https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720#fact-resource-facts-0) Copperstone · gold #### 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 factor: High confidence Measured Resource category - Positive factor: High grade for an underground gold project - Positive factor: Contributes to significant overall resource growth Evidence · table > 2,198 Context: Measured #### Tags used in scoring **Measured Resource** Polarity: positive Definition: Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves. Why it applies: category is "measured" **Cut-off Disclosed** Polarity: positive Definition: Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison. Why it applies: cutoff\_grade is stated **QP/CP Signed** Polarity: positive Definition: 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 Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with NI 43-101 \(Canada\) — high reporting standard. Why it applies: reporting\_standards includes ni\_43\_101 **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: the release compares against a previous estimate **PEA-Supporting** Polarity: neutral Definition: Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study. Why it applies: the release names the study this estimate supports **PFS-Supporting** Polarity: neutral Definition: 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-Supporting** Polarity: neutral Definition: 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 ### indicated [Link to this fact](https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720#fact-resource-facts-1) Copperstone · gold #### 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 factor: Indicated Resource category provides good geological confidence - Positive factor: Strong grade for an underground gold project - Positive factor: Contributes to significant overall resource growth Evidence · table > 1,856 Context: Indicated #### Tags used in scoring **Indicated Resource** Polarity: positive Definition: Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves. Why it applies: category is "indicated" **Cut-off Disclosed** Polarity: positive Definition: Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison. Why it applies: cutoff\_grade is stated **QP/CP Signed** Polarity: positive Definition: 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 Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with NI 43-101 \(Canada\) — high reporting standard. Why it applies: reporting\_standards includes ni\_43\_101 **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: the release compares against a previous estimate **PEA-Supporting** Polarity: neutral Definition: Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study. Why it applies: the release names the study this estimate supports **PFS-Supporting** Polarity: neutral Definition: 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-Supporting** Polarity: neutral Definition: 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 ### indicated [Link to this fact](https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720#fact-resource-facts-2) Copperstone · gold #### 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 factor: Total Measured & Indicated Resources show a 110% increase in contained gold ounces compared to previous estimate - Positive factor: High confidence resource base for economic studies - Positive factor: Strong average grade for an underground gold project Evidence · table > 4,054 Context: Total Measured & Indicated #### Tags used in scoring **Indicated Resource** Polarity: positive Definition: Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves. Why it applies: category is "indicated" **Cut-off Disclosed** Polarity: positive Definition: Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison. Why it applies: cutoff\_grade is stated **QP/CP Signed** Polarity: positive Definition: 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 Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with NI 43-101 \(Canada\) — high reporting standard. Why it applies: reporting\_standards includes ni\_43\_101 **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: the release compares against a previous estimate **PEA-Supporting** Polarity: neutral Definition: Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study. Why it applies: the release names the study this estimate supports **PFS-Supporting** Polarity: neutral Definition: 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-Supporting** Polarity: neutral Definition: 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 ### inferred [Link to this fact](https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720#fact-resource-facts-3) Copperstone · gold #### 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 factor: Adds to the overall resource base - Positive factor: Potential for future conversion to higher confidence categories - Negative factor: Inferred category has lower geological confidence and cannot support economic studies alone Evidence · table > 401 Context: Inferred #### Tags used in scoring **Inferred Resource** Polarity: negative Definition: Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone. Why it applies: category is "inferred" **Cut-off Disclosed** Polarity: positive Definition: Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison. Why it applies: cutoff\_grade is stated **QP/CP Signed** Polarity: positive Definition: 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 Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with NI 43-101 \(Canada\) — high reporting standard. Why it applies: reporting\_standards includes ni\_43\_101 **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: the release compares against a previous estimate **PEA-Supporting** Polarity: neutral Definition: Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study. Why it applies: the release names the study this estimate supports **PFS-Supporting** Polarity: neutral Definition: 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-Supporting** Polarity: neutral Definition: 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 ### proven [Link to this fact](https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720#fact-resource-facts-4) Copperstone · gold #### 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 factor: Maiden Proven Reserve demonstrates high confidence and economic viability - Positive factor: High grade for an underground gold project - Positive factor: Forms a strong base for mine planning Evidence · table > 1,052 Context: Proven #### Tags used in scoring **Proven Reserve** Polarity: positive Definition: Measured Resource with demonstrated economic viability after applying modifying factors. Why it applies: category is "proven" **Cut-off Disclosed** Polarity: positive Definition: Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison. Why it applies: cutoff\_grade is stated **QP/CP Signed** Polarity: positive Definition: 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 Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with NI 43-101 \(Canada\) — high reporting standard. Why it applies: reporting\_standards includes ni\_43\_101 **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: the release compares against a previous estimate **PEA-Supporting** Polarity: neutral Definition: Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study. Why it applies: the release names the study this estimate supports **PFS-Supporting** Polarity: neutral Definition: 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-Supporting** Polarity: neutral Definition: 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 ### probable [Link to this fact](https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720#fact-resource-facts-5) Copperstone · gold #### 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 factor: Maiden Probable Reserve demonstrates economic viability - Positive factor: Strong grade for an underground gold project - Positive factor: Adds to the overall reserve base for mine planning Evidence · table > 882 Context: Probable #### Tags used in scoring **Probable Reserve** Polarity: positive Definition: Indicated Resource with demonstrated economic viability after applying modifying factors. Why it applies: category is "probable" **Cut-off Disclosed** Polarity: positive Definition: Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison. Why it applies: cutoff\_grade is stated **QP/CP Signed** Polarity: positive Definition: 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 Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with NI 43-101 \(Canada\) — high reporting standard. Why it applies: reporting\_standards includes ni\_43\_101 **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: the release compares against a previous estimate **PEA-Supporting** Polarity: neutral Definition: Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study. Why it applies: the release names the study this estimate supports **PFS-Supporting** Polarity: neutral Definition: 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-Supporting** Polarity: neutral Definition: 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 ### probable [Link to this fact](https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720#fact-resource-facts-6) Copperstone · gold #### 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 factor: Maiden Total Proven & Probable Reserves provide a robust economic foundation for the project - Positive factor: Strong average grade for an underground gold project - Positive factor: Supports the positive PFS and construction decision Evidence · table > 1,934 Context: Total Proven & Probable #### Tags used in scoring **Probable Reserve** Polarity: positive Definition: Indicated Resource with demonstrated economic viability after applying modifying factors. Why it applies: category is "probable" **Cut-off Disclosed** Polarity: positive Definition: Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison. Why it applies: cutoff\_grade is stated **QP/CP Signed** Polarity: positive Definition: 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 Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with NI 43-101 \(Canada\) — high reporting standard. Why it applies: reporting\_standards includes ni\_43\_101 **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: the release compares against a previous estimate **PEA-Supporting** Polarity: neutral Definition: Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study. Why it applies: the release names the study this estimate supports **PFS-Supporting** Polarity: neutral Definition: 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-Supporting** Polarity: neutral Definition: 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 8 [Link to this fact](https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720#fact-resource-facts-8) Copperstone · gold #### 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 factor: Robust mine life of 6.3 years with significant total gold production - Positive factor: Low all-in sustaining costs \($1,314/oz\) and cash operating costs \($1,070/oz\) - Positive factor: Low initial capital intensity \($58.3M\) - Positive factor: 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 Undisclosed** Polarity: negative Definition: High-grade interval reported without stating the cut-off grade used for compositing. Why it applies: no cutoff\_grade was stated **NI 43-101 Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with NI 43-101 \(Canada\) — high reporting standard. Why it applies: reporting\_standards includes ni\_43\_101 **No Contained Metal** Polarity: negative Definition: Tonnage and grade reported but contained metal not calculated or disclosed — incomplete reporting. Why it applies: contained\_metal was not reported **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: the release compares against a previous estimate **PEA-Supporting** Polarity: neutral Definition: Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study. Why it applies: the release names the study this estimate supports **PFS-Supporting** Polarity: neutral Definition: 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-Supporting** Polarity: neutral Definition: 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 route [Link to this fact](https://atlas-extractions.minestarters.com/news/minera-alamos-announces-positive-pre-feasibility-study-for-the-copperstone-gold--12e92e77-9bb6-4519-b426-c0dc1ec93720#fact-metallurgical-facts-7) Copperstone · gold #### 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 factor: Exceptional gold recovery rate of 96% - Positive factor: Hybrid process designed for flexibility and high recoveries - Positive factor: Supports strong project economics Evidence · text > projected overall gold recovery of approximately 96% #### Tags used in scoring **Mill Route** Polarity: neutral Definition: Processing via mill or concentrator \(CIL, CIP, tank leach, flotation\). Why it applies: processing\_route matches the mill\_cil signal **High Recovery** Polarity: positive Definition: 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.