# Cowboy State Mine Study Strengthens Foundation for Domestic U.S. Rare Earth Supply Canonical Atlas analysis: https://atlas-staging.minestarters.com/news/cowboy-state-mine-study-strengthens-foundation-for-domestic-u-s-rare-earth-suppl--854c1857-4081-4670-8a63-45d37d5fc3c4 Original source: https://www.globenewswire.com/news-release/2026/09/30/3372074/0/en/cowboy-state-mine-study-strengthens-foundation-for-domestic-u-s-rare-earth-supply.html Publisher: globenewswire Original announcement: 2026-09-30T00:00:00.000Z Analysis by Minestarters Atlas Atlas analysis published: 2026-09-30T14:34:49.982Z Atlas analysis updated: 2026-09-30T14:34:49.982Z - Company: American Rare Earths Limited - Ticker: ARR - Exchange: Unavailable - Region: Wyoming - Primary commodity: Rare earth - Secondary commodities: Neodymium, Praseodymium, Terbium, Dysprosium, Samarium, Europium, Gadolinium - Document categories: Metallurgy, Resource update - Extracted: 2026-09-30 14:34:50 UTC Narrative sentiment: 0.40 · Bullish ## Minestarters Atlas summary American Rare Earths has released an updated Scoping Study for the Cowboy State Mine in Wyoming, projecting a 4.5 Mtpa operation with a 26-year mine life. The study reports an after-tax NPV of US$1.07 billion at an 8% real discount rate, supported by increased NdPr oxide production of approximately 2,500 tonnes per annum. Reasoning: The updated scoping study demonstrates a significantly larger scale project with higher NPV and longer life, though it adopts more conservative recovery and higher capital assumptions. - Positive factor: Significant increase in planned throughput \(4.5 Mtpa vs 3.0 Mtpa\) - Positive factor: Increased annual NdPr oxide production \(2,500 t vs 1,833 t\) - Positive factor: Extended mine life \(26 years vs 20 years\) - Positive factor: Substantial NPV increase at 8% discount rate \($1.07B\) - Positive factor: Strategic domestic U.S. supply chain positioning - Negative factor: Lowered product recoveries compared to 2025 study - Negative factor: Higher initial capital requirement \($900M vs $456M\) - Negative factor: Increased contingency \(30% vs 20%\) - Negative factor: Longer payback period \(6.9 years vs 2.7 years\) Facts used in scoring: 6 ## Classification and evidence **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 Scoping Study for the Cowboy State Mine, comparing 2026 estimates to 2025 base case. Evidence · text > The 2026 Scoping Study is an update on the work completed to date and replaces the previously issued 2025 Scoping study **Low Recovery** Polarity: negative Definition: Recovery below the weak band for the commodity and processing route. Why it applies: The 2026 study adopts significantly lower product recoveries for heavy rare earths compared to the 2025 study. Evidence · table > 28.7 Context: Terbium oxide **Mill Route** Polarity: neutral Definition: Processing via mill or concentrator \(CIL, CIP, tank leach, flotation\). Why it applies: the document describes a flotation route \("concentrate"\) **Single Domain Only** Polarity: negative Definition: Testing limited to one composite or domain — representativeness not established. Why it applies: only one composite was tested ## Extracted facts Stored fact records: 6. Some facts used in scoring do not have a stored record. ## Resource Estimates (2) ### indicated [Link to this fact](https://atlas-staging.minestarters.com/news/cowboy-state-mine-study-strengthens-foundation-for-domestic-u-s-rare-earth-suppl--854c1857-4081-4670-8a63-45d37d5fc3c4#fact-resource-facts-0) Halleck Creek · neodymium #### Identity - Project: Halleck Creek - Commodity: neodymium - Region: wyoming - Reported Region: Wyoming - Ticker: ARR #### Resource scope - Estimate type: resource - Reporting standards: jorc - QP Signed: Yes - Qualified person names: Kelton Smith, Patrick A Sobecke, Alfred J Gillman, Mark W. Travis - Resource group id: resource:b9abdf6e1cbd23577766 - Deposit or zone: Cowboy State Mine #### Resource Data - Category: indicated - Tonnes: 135000000 - Grade: 3292 - Grade Unit: ppm #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-30T00:00:00.000Z Reasoning: Base resource grade for the project. - Positive factor: Large scale resource Evidence · text > Halleck Creek Mineral Resource includes... approximately 2.63 billion tonnes at 3,292 ppm total rare earth oxides #### 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 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 **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 **JORC Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with JORC Code \(Australia\) — high reporting standard. Why it applies: reporting\_standards includes jorc **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 ### indicated [Link to this fact](https://atlas-staging.minestarters.com/news/cowboy-state-mine-study-strengthens-foundation-for-domestic-u-s-rare-earth-suppl--854c1857-4081-4670-8a63-45d37d5fc3c4#fact-resource-facts-1) Halleck Creek · praseodymium #### Identity - Project: Halleck Creek - Commodity: praseodymium - Region: wyoming - Reported Region: Wyoming - Ticker: ARR #### Resource scope - Estimate type: resource - Reporting standards: jorc - QP Signed: Yes - Qualified person names: Kelton Smith, Patrick A Sobecke, Alfred J Gillman, Mark W. Travis - Resource group id: resource:b9abdf6e1cbd23577766 - Deposit or zone: Cowboy State Mine #### Resource Data - Category: indicated - Tonnes: 135000000 - Grade: 3292 - Grade Unit: ppm #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-30T00:00:00.000Z Reasoning: Base resource grade for the project. - Positive factor: Large scale resource Evidence · text > Halleck Creek Mineral Resource includes... approximately 2.63 billion tonnes at 3,292 ppm total rare earth oxides #### 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 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 **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 **JORC Compliant** Polarity: positive Definition: Resource estimate prepared in compliance with JORC Code \(Australia\) — high reporting standard. Why it applies: reporting\_standards includes jorc **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 ## Metallurgical Results (4) ### Fact 1 [Link to this fact](https://atlas-staging.minestarters.com/news/cowboy-state-mine-study-strengthens-foundation-for-domestic-u-s-rare-earth-suppl--854c1857-4081-4670-8a63-45d37d5fc3c4#fact-metallurgical-facts-2) Cowboy State Mine · neodymium oxide #### Identity - Project: Cowboy State Mine - Commodity: neodymium oxide - Region: wyoming - Reported Region: Wyoming - Ticker: ARR #### Test Work - Sample: 2026 Scoping Study base case #### Recovery - Recovery: 58.2 % #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-30T00:00:00.000Z Reasoning: Recovery decreased from 63.9% in the 2025 study to 58.2% in the 2026 study. - Negative factor: Lower recovery than 2025 study Evidence · table > 58.2 Context: NdPr oxide ### Fact 2 [Link to this fact](https://atlas-staging.minestarters.com/news/cowboy-state-mine-study-strengthens-foundation-for-domestic-u-s-rare-earth-suppl--854c1857-4081-4670-8a63-45d37d5fc3c4#fact-metallurgical-facts-3) Cowboy State Mine · terbium oxide #### Identity - Project: Cowboy State Mine - Commodity: terbium oxide - Region: wyoming - Reported Region: Wyoming - Ticker: ARR #### Test Work - Sample: 2026 Scoping Study base case #### Recovery - Recovery: 28.7 % #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-30T00:00:00.000Z Reasoning: Terbium oxide recovery dropped significantly from 70.2% to 28.7%. - Negative factor: Significant reduction in recovery Evidence · table > 28.7 Context: Terbium oxide ### Fact 3 [Link to this fact](https://atlas-staging.minestarters.com/news/cowboy-state-mine-study-strengthens-foundation-for-domestic-u-s-rare-earth-suppl--854c1857-4081-4670-8a63-45d37d5fc3c4#fact-metallurgical-facts-4) Cowboy State Mine · dysprosium oxide #### Identity - Project: Cowboy State Mine - Commodity: dysprosium oxide - Region: wyoming - Reported Region: Wyoming - Ticker: ARR #### Test Work - Sample: 2026 Scoping Study base case #### Recovery - Recovery: 12.4 % #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-30T00:00:00.000Z Reasoning: Dysprosium oxide recovery dropped from 66.5% to 12.4%. - Negative factor: Severe reduction in recovery Evidence · table > 12.4 Context: Dysprosium oxide ### Fact 4 [Link to this fact](https://atlas-staging.minestarters.com/news/cowboy-state-mine-study-strengthens-foundation-for-domestic-u-s-rare-earth-suppl--854c1857-4081-4670-8a63-45d37d5fc3c4#fact-metallurgical-facts-5) Cowboy State Mine · samarium, europium and gadolinium \(seg\) product #### Identity - Project: Cowboy State Mine - Commodity: samarium, europium and gadolinium \(seg\) product - Region: wyoming - Reported Region: Wyoming - Ticker: ARR #### Test Work - Sample: 2026 Scoping Study base case #### Recovery - Recovery: 25.8 % #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-30T00:00:00.000Z Reasoning: SEG product recovery dropped from 70.1% to 25.8%. - Negative factor: Reduction in recovery Evidence · table > 25.8 Context: Samarium, europium and gadolinium \(SEG\) product ## 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.