# Gunnison Copper Announces Updated Preliminary Economic Assessment of Its Flagship Gunnison Copper Project Reporting Post-Tax NPV8 of US$2.0 Billion Canonical Atlas analysis: https://atlas-extractions.minestarters.com/news/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02 Original source: https://money.tmx.com/en/quote/GCU/news/8849645577425210/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi Publisher: tmx Original announcement: 2026-02-26T00:00:00.000Z Analysis by Minestarters Atlas Atlas analysis published: Unknown date Atlas analysis updated: Unknown date - Company: Gunnison Copper Corp. - Ticker: GCU - Exchange: TSX - Region: Arizona, United States - Primary commodity: Copper - Secondary commodities: Zinc, Silver - Document categories: Resource update, Metallurgy, Other - Extracted: 2026-09-12 04:02:53 UTC Narrative sentiment: 0.80 · Bullish ## Minestarters Atlas summary Gunnison Copper announced an updated Preliminary Economic Assessment \(PEA\) for its Gunnison Copper Project, reporting a post-tax NPV8 of US$2.0 billion and an Internal Rate of Return \(IRR\) of 22.7% at a copper price of $4.60/lb. This represents a 55% increase in NPV8 compared to the previous 2024 PEA, driven by the inclusion of the high-grade Strong & Harris satellite deposit, material sorting, and the addition of cement and limestone co-products. The project outlines a 21-year mine life with average annual copper cathode production of 174 million pounds for the first 15 years and competitive cash costs. Reasoning: The updated Preliminary Economic Assessment demonstrates significantly improved project economics with a substantial increase in NPV and a robust IRR, driven by operational enhancements and the integration of a new high-grade deposit and co-products. While preliminary, the results are compelling for a copper development project, though some metallurgical and permitting risks remain. - Positive factor: High post-tax NPV8 of US$2.0 billion at base case copper price. - Positive factor: Strong IRR of 22.7% at base case copper price. - Positive factor: Significant 55% increase in NPV8 compared to the previous 2024 PEA. - Positive factor: Inclusion of high-grade Strong & Harris satellite deposit adds to project economics. - Positive factor: Addition of cement and limestone co-products diversifies revenue streams and improves project value. - Positive factor: Competitive cash costs \($1.69/lb Cu C1\) position the project in the lower half of the global cost curve. - Positive factor: High oxide/enriched copper recoveries \(90.2%\) for the heap leach process. - Positive factor: Long mine life of 21 years provides sustained production potential. - Positive factor: NI 43-101 compliant report prepared by multiple independent Qualified Persons. - Negative factor: The PEA is preliminary in nature and includes inferred mineral resources, which are considered speculative. - Negative factor: Primary sulfide recoveries are lower \(59.9%\), indicating potential challenges for this material type. - Negative factor: Identified risks include permitting difficulties, slope stability, blasting costs, copper recovery unpredictability, acid consumption, and leach pad flow attenuation. - Negative factor: Current metallurgical testwork is not yet at pilot scale, with pilot testing recommended for further investigation. Low confidence — this extraction should be reviewed alongside the original source. Facts used in scoring: 9 ## Classification and evidence **NI 43-101 Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with NI 43-101 \(Canada\) — high reporting standard. Why it applies: The document states the PEA is an 'updated NI 43-101 Preliminary Economic Assessment'. Evidence · text > updated NI 43-101 Preliminary Economic Assessment **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 report is 'prepared under the supervision of John Woodson, PE, SME-RM, of M3 Engineering & Technology Corporation, Tucson, Arizona, who is a Qualified Person' and lists other Qualified Persons. Evidence · text > prepared under the supervision of John Woodson, PE, SME-RM, of M3 Engineering & Technology Corporation, Tucson, Arizona, who is a Qualified Person **PEA-Supporting** Polarity: neutral Definition: Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study. Why it applies: The document is an 'Updated Preliminary Economic Assessment'. Evidence · text > Updated Preliminary Economic Assessment **Tonnage Growth** Polarity: positive Definition: Tonnage increase reaching the strong tier vs prior estimate, with grade maintained or improved. Why it applies: The 2026 PEA NPV8% of $1,952M is an increase of $692M \(+55%\) from the 2024 PEA NPV8% of $1,260M. Evidence · text > The 2026 PEA NPV8% of $1,952M is an increase of $692M \(+55%\) from the 2024 PEA NPV8% of $1,260M. **Inferred Resource** Polarity: negative Definition: Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone. Why it applies: The PEA 'includes inferred mineral resources that are considered too speculative geologically to have the economic considerations applied to them'. Evidence · text > includes inferred mineral resources that are considered too speculative geologically to have the economic considerations applied to them **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 Gunnison deposit mineral resources include a 'Measured' category. Evidence · table > Measured Context: Resource Class **Indicated Resource** Polarity: positive Definition: Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves. Why it applies: The Gunnison deposit mineral resources include an 'Indicated' category. Evidence · table > Indicated Context: Resource Class **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: The document announces an 'Updated Preliminary Economic Assessment' which includes updated mineral resource estimates for the Gunnison deposit. Evidence · text > Updated Preliminary Economic Assessment **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 Gunnison deposit mineral resources are reported with 'an internal cut-off grade of 0.05% TCu for oxide and transition, and 0.1% TCu for sulfide'. Evidence · text > an internal cut-off grade of 0.05% TCu for oxide and transition, and 0.1% TCu for sulfide **Maiden Resource** Polarity: neutral Definition: First formal MRE for the project — establishes baseline but typically exploration-stage with high Inferred component. No prior estimate exists, so every change band is not applicable. Why it applies: The Strong & Harris satellite deposit is newly included in this PEA, with its prior technical report superseded. Evidence · text > As Strong & Harris is now included within the PEA, the prior technical report filed on SEDAR+ at www.sedarplus.ca entitled: "Estimated Mineral Resources and Preliminary Economic Analysis, Strong and Harris Copper-Zinc-Silver Project, Cochise County, Arizona" dated effective of September 9, 2021 has been superseded and is no longer a current technical report. **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: Oxide / Enriched Recoveries are reported at 90.2% CuTSol, which is excellent for a heap leach process. Evidence · table > 90.2% Context: Oxide / Enriched Recoveries **Low Recovery** Polarity: negative Definition: Recovery below the weak band for the commodity and processing route. Why it applies: Primary Sulfide Recoveries are reported at 59.9% CuSu, which is below the weak band for typical copper processing routes. Evidence · table > 59.9% Context: Primary Sulfide Recoveries \(years 10 to 21\) **Heap Leach Route** Polarity: neutral Definition: Processing via heap leach — lower CAPEX and OPEX, lower recovery expected. Why it applies: The project is described as a 'Conventional open pit, heap leach, SX/EW operation'. Evidence · text > Conventional open pit, heap leach, SX/EW operation **Bench Scale Only** Polarity: negative Definition: Only preliminary bench tests completed — no locked-cycle or pilot work. Why it applies: The document states 'Pilot metallurgical heap leach testing is recommended', indicating that current testwork is not yet at pilot scale. Evidence · text > Pilot metallurgical heap leach testing is recommended ## Extracted facts Stored fact records: 9. Some facts used in scoring do not have a stored record. ## Resource Estimates (6) ### measured [Link to this fact](https://atlas-extractions.minestarters.com/news/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02#fact-resource-facts-0) Gunnison Copper Project · copper #### Identity - Project: Gunnison Copper Project - Commodity: copper - Region: usa\_az - Reported Region: Arizona, United States - Ticker: GCU #### Resource scope - Estimate type: resource - Effective date: 2026-01-23T00:00:00.000Z - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Jeffrey Bickel - Resource group id: resource:519875132ff17dc3f105 - Deposit or zone: Gunnison Deposit - Mining method: open\_pit - Ownership percent: 100 % #### Resource Data - Category: measured - Tonnes: 173720000 - Grade: 0.37 - Grade Unit: % - Contained Metal: 1423 - Contained Unit: m lbs - Cutoff Grade: 0.05 - Cutoff Unit: % TCu #### Prior Estimate - Resource Date: 2026-01-23 #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-02-26T00:00:00.000Z Reasoning: The Measured resource provides a high level of geological confidence for a significant portion of the Gunnison deposit. - Positive factor: High confidence Measured category resource. Evidence · table > 0.37 Context: 191.5 #### 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 **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/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02#fact-resource-facts-1) Gunnison Copper Project · copper #### Identity - Project: Gunnison Copper Project - Commodity: copper - Region: usa\_az - Reported Region: Arizona, United States - Ticker: GCU #### Resource scope - Estimate type: resource - Effective date: 2026-01-23T00:00:00.000Z - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Jeffrey Bickel - Resource group id: resource:34a6a1e896dbeef7b95e - Deposit or zone: Gunnison Deposit - Mining method: open\_pit - Ownership percent: 100 % #### Resource Data - Category: indicated - Tonnes: 593870000 - Grade: 0.31 - Grade Unit: % - Contained Metal: 3768 - Contained Unit: m lbs - Cutoff Grade: 0.05 - Cutoff Unit: % TCu #### Prior Estimate - Resource Date: 2026-01-23 #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-02-26T00:00:00.000Z Reasoning: The Indicated resource forms the largest part of the Gunnison deposit, supporting further economic studies. - Positive factor: Indicated resource provides good geological confidence for a substantial portion of the deposit. Evidence · table > 0.31 Context: 654.5 #### 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 **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/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02#fact-resource-facts-2) Gunnison Copper Project · copper #### Identity - Project: Gunnison Copper Project - Commodity: copper - Region: usa\_az - Reported Region: Arizona, United States - Ticker: GCU #### Resource scope - Estimate type: resource - Effective date: 2026-01-23T00:00:00.000Z - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Jeffrey Bickel - Resource group id: resource:dc61374db435e7c129af - Deposit or zone: Gunnison Deposit - Mining method: open\_pit - Ownership percent: 100 % #### Resource Data - Category: inferred - Tonnes: 85255000 - Grade: 0.21 - Grade Unit: % - Contained Metal: 397 - Contained Unit: m lbs - Cutoff Grade: 0.05 - Cutoff Unit: % TCu #### Prior Estimate - Resource Date: 2026-01-23 #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-02-26T00:00:00.000Z Reasoning: The Inferred resource, while contributing to total contained metal, carries a lower level of geological confidence and is speculative for economic studies. - Negative factor: Inferred resources are considered too speculative geologically for economic considerations. Evidence · table > 0.21 Context: 94 #### 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 **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/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02#fact-resource-facts-3) Gunnison Copper Project · copper #### Identity - Project: Gunnison Copper Project - Commodity: copper - Region: usa\_az - Reported Region: Arizona, United States - Ticker: GCU #### Resource scope - Estimate type: resource - Effective date: 2026-01-23T00:00:00.000Z - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Jeffrey Bickel - Resource group id: resource:54a5b0e09e9f2927309e - Deposit or zone: Strong & Harris Deposit - Mining method: open\_pit - Ownership percent: 100 % #### Resource Data - Category: inferred - Tonnes: 68946000 - Grade: 0.49 - Grade Unit: % - Contained Metal: 740 - Contained Unit: m lbs - Cutoff Grade: 0.07 - Cutoff Unit: % TCu #### Prior Estimate - Resource Date: 2026-01-23 #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-02-26T00:00:00.000Z Reasoning: The Strong & Harris deposit, newly included in the PEA, adds a significant amount of high-grade copper in the Inferred category, contributing positively to project economics despite its speculative nature. - Positive factor: High-grade material from the satellite deposit significantly enhances project economics. - Positive factor: New inclusion in the PEA adds to the overall resource base. - Negative factor: Resource is entirely in the Inferred category, which is speculative. Evidence · table > 0.49 Context: 76 #### 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 **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/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02#fact-resource-facts-4) Gunnison Copper Project · zinc #### Identity - Project: Gunnison Copper Project - Commodity: zinc - Region: usa\_az - Reported Region: Arizona, United States - Ticker: GCU #### Resource scope - Estimate type: resource - Effective date: 2026-01-23T00:00:00.000Z - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Jeffrey Bickel - Resource group id: resource:54a5b0e09e9f2927309e - Deposit or zone: Strong & Harris Deposit - Mining method: open\_pit - Ownership percent: 100 % #### Resource Data - Category: inferred - Tonnes: 68946000 - Grade: 0.56 - Grade Unit: % - Contained Metal: 856 - Contained Unit: m lbs - Cutoff Grade: 0.07 - Cutoff Unit: % TCu #### Prior Estimate - Resource Date: 2026-01-23 #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-02-26T00:00:00.000Z Reasoning: The Strong & Harris deposit contains a significant zinc component in the Inferred category, representing potential future value, though not yet incorporated into the current economic plan. - Positive factor: Zinc is a valuable byproduct from the newly included Strong & Harris deposit. - Negative factor: Resource is entirely in the Inferred category, which is speculative. - Negative factor: No credits for zinc are included in the current mine and processing plan, indicating it's an opportunity for later. Evidence · table > 0.56 Context: 76 #### 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 **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/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02#fact-resource-facts-5) Gunnison Copper Project · silver #### Identity - Project: Gunnison Copper Project - Commodity: silver - Region: usa\_az - Reported Region: Arizona, United States - Ticker: GCU #### Resource scope - Estimate type: resource - Effective date: 2026-01-23T00:00:00.000Z - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Jeffrey Bickel - Resource group id: resource:54a5b0e09e9f2927309e - Deposit or zone: Strong & Harris Deposit - Mining method: open\_pit - Ownership percent: 100 % #### Resource Data - Category: inferred - Tonnes: 68946000 - Contained Metal: 9 - Contained Unit: m oz - Cutoff Grade: 0.07 - Cutoff Unit: % TCu #### Prior Estimate - Resource Date: 2026-01-23 #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-02-26T00:00:00.000Z Reasoning: The Strong & Harris deposit contains a silver component in the Inferred category, representing potential future value, though not yet incorporated into the current economic plan. - Positive factor: Silver is a valuable byproduct from the newly included Strong & Harris deposit. - Negative factor: Resource is entirely in the Inferred category, which is speculative. - Negative factor: No credits for silver are included in the current mine and processing plan, indicating it's an opportunity for later. Evidence · table > 0.12 Context: 76 #### 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 **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 (3) ### heap leach [Link to this fact](https://atlas-extractions.minestarters.com/news/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02#fact-metallurgical-facts-6) Gunnison Copper Project · copper #### Identity - Project: Gunnison Copper Project - Commodity: copper - Region: usa\_az - Reported Region: Arizona, United States - Ticker: GCU #### Test Work - Program Status: preliminary - Test Type: heap leach - Processing Route: heap leach, SX/EW #### Recovery - Recovery: 68 % - Recovery Basis: actual\_test #### Lab - Laboratory: Skyline Assayers & Laboratories - Consultant: Terence P. McNulty #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-02-26T00:00:00.000Z Reasoning: The global copper recovery of 68.0% is a reasonable overall figure for a heap leach operation, but further pilot testing is recommended to confirm performance. - Negative factor: Pilot metallurgical heap leach testing is recommended, suggesting current testwork is not yet at pilot scale. Evidence · table > 68.0% Context: Copper Recovery - Global #### Tags used in scoring **Heap Leach Route** Polarity: neutral Definition: Processing via heap leach — lower CAPEX and OPEX, lower recovery expected. Why it applies: processing\_route matches the heap\_leach signal **Byproduct Commodity** Polarity: neutral Definition: The tested commodity is a byproduct rather than the primary economic driver. Why it applies: the release describes a byproduct credit ### heap leach [Link to this fact](https://atlas-extractions.minestarters.com/news/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02#fact-metallurgical-facts-7) Gunnison Copper Project · copper #### Identity - Project: Gunnison Copper Project - Commodity: copper - Region: usa\_az - Reported Region: Arizona, United States - Ticker: GCU #### Test Work - Program Status: preliminary - Test Type: heap leach - Processing Route: heap leach, SX/EW #### Recovery - Recovery: 90.2 % - Recovery Basis: actual\_test #### Lab - Laboratory: Skyline Assayers & Laboratories - Consultant: Terence P. McNulty #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-02-26T00:00:00.000Z Reasoning: The 90.2% recovery for oxide/enriched material is a strong result for a heap leach operation, indicating good amenability of the primary ore type. - Positive factor: High recovery for oxide/enriched material is excellent for a heap leach process. - Negative factor: Pilot metallurgical heap leach testing is recommended, suggesting current testwork is not yet at pilot scale. Evidence · table > 90.2% Context: Oxide / Enriched Recoveries #### Tags used in scoring **Heap Leach Route** Polarity: neutral Definition: Processing via heap leach — lower CAPEX and OPEX, lower recovery expected. Why it applies: processing\_route matches the heap\_leach signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 90.2% is at or above the exceptional band \(80%\) **Byproduct Commodity** Polarity: neutral Definition: The tested commodity is a byproduct rather than the primary economic driver. Why it applies: the release describes a byproduct credit ### heap leach [Link to this fact](https://atlas-extractions.minestarters.com/news/gunnison-copper-announces-updated-preliminary-economic-assessment-of-its-flagshi--d4d649b7-a734-4565-a215-24cbf6c04f02#fact-metallurgical-facts-8) Gunnison Copper Project · copper #### Identity - Project: Gunnison Copper Project - Commodity: copper - Region: usa\_az - Reported Region: Arizona, United States - Ticker: GCU #### Test Work - Program Status: preliminary - Test Type: heap leach - Processing Route: heap leach, SX/EW #### Recovery - Recovery: 59.9 % - Recovery Basis: actual\_test #### Lab - Laboratory: Skyline Assayers & Laboratories - Consultant: Terence P. McNulty #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-02-26T00:00:00.000Z Reasoning: The 59.9% recovery for primary sulfide material is relatively low, suggesting this ore type may require further optimization or different processing approaches to improve economics. - Negative factor: Low recovery for primary sulfide material indicates potential processing challenges for this ore type. - Negative factor: Pilot metallurgical heap leach testing is recommended, suggesting current testwork is not yet at pilot scale. Evidence · table > 59.9% Context: Primary Sulfide Recoveries \(years 10 to 21\) #### Tags used in scoring **Heap Leach Route** Polarity: neutral Definition: Processing via heap leach — lower CAPEX and OPEX, lower recovery expected. Why it applies: processing\_route matches the heap\_leach signal **Byproduct Commodity** Polarity: neutral Definition: The tested commodity is a byproduct rather than the primary economic driver. Why it applies: the release describes a byproduct credit ## 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.