# BTR: Sandstone PFS Metallurgy Delivers 94% Gold Recovery Canonical Atlas analysis: https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a Original source: https://www.asx.com.au/asx/v2/statistics/displayAnnouncement.do?display=pdf&idsId=03143254 Publisher: asx Original announcement: 2026-09-23T23:30:00.000Z Analysis by Minestarters Atlas Atlas analysis published: 2026-09-24T00:22:05.290Z Atlas analysis updated: 2026-09-24T00:22:05.290Z - Company: Brightstar Resources Limited - Ticker: BTR - Exchange: ASX - Region: Western Australia - Primary commodity: Gold - Secondary commodities: None reported - Document categories: Metallurgy - Extracted: 2026-09-24 00:22:06 UTC Narrative sentiment: 0.90 · Bullish ## Minestarters Atlas summary Brightstar Resources announced metallurgical testwork results for its Sandstone Gold Project, delivering average gold recoveries of 94% using a conventional gravity and CIL flowsheet. The results, which cover 80% of the 2.9Moz Mineral Resource, confirm a simple, low-cost processing route with high gravity gold recovery and low reagent consumption, supporting the ongoing Pre-Feasibility Study due in December Q4 2026. Reasoning: PFS-level metallurgical testwork confirms high average gold recoveries of 95.7% \(CIL\) across 80% of the 2.9Moz Sandstone Gold Project, using a conventional gravity and CIL flowsheet, with low reagent consumption and no refractory characteristics, significantly de-risking the project's processing route. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Facts used in scoring: 13 ## Classification and evidence **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: The metallurgical testwork delivered average gold recoveries of 94% and overall CIL recoveries averaged 95.7%, which is at or above the exceptional band for the CIL processing route. Evidence · text > average gold recoveries of 94% **Free Milling** Polarity: positive Definition: Simple, clean ore amenable to standard processing without oxidation. Why it applies: The testwork identified no refractory recovery characteristics, preg-robbing, or other complex processing issues, indicating the ore is amenable to standard processing. Evidence · text > No refractory recovery characteristics have been identified in any deposit at Sandstone. **Multi-Domain Tested** Polarity: positive Definition: Variability across ore domains \(oxide, transition, fresh\) has been addressed. Why it applies: The testwork covered master and variability composites from nine deposits and included oxide, transitional, and fresh ore types, representing approximately 80% of the Sandstone Mineral Resource. Evidence · text > The deposits tested represent approximately 80% of the Sandstone Mineral Resource; results are being incorporated into the Sandstone PFS **QP/CP Signed** Polarity: positive Story-specific tag 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 metallurgical results are based on information reviewed by Mr Alex Borger, a Member of The Australasian Institute of Mining and Metallurgy \(AusIMM\), who qualifies as a Competent Person. Evidence · text > Mr Alex Borger, BSc \(Extractive Metallurgy and Chemistry\), who is a Member of The Australasian Institute of Mining and Metallurgy \(AusIMM\). **JORC Compliant** Polarity: positive Story-specific tag Definition: Resource estimate prepared in compliance with JORC Code \(Australia\) — high reporting standard. Why it applies: The Competent Person Statement confirms that the information is reported in accordance with the JORC Code 2012. Evidence · text > Competent Person as defined in the 2012 Edition of the “Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves” \(JORC Code 2012\). **PFS-Supporting** Polarity: neutral Story-specific tag Definition: Resource estimate prepared to support a Pre-Feasibility Study — requires adequate M&I component. Why it applies: The metallurgical testwork program is being completed as part of the Pre-Feasibility Study \(PFS\) on the Sandstone Gold Project. Evidence · text > metallurgical testwork program being completed as part of the Pre-Feasibility Study \(PFS\) on its Sandstone Gold Project **Mill Route** Polarity: neutral Definition: Processing via mill or concentrator \(CIL, CIP, tank leach, flotation\). Why it applies: The confirmed processing route is a conventional gravity and carbon-in-leach \(CIL\) circuit, which is a mill-based process. Evidence · text > conventional gravity and carbon-in-leach \(CIL\) circuit **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: A significant proportion of the gold is recoverable by gravity alone, with master composites averaging 42% gravity recovery. Evidence · text > A significant proportion of the gold is recoverable by gravity alone **Deleterious Elements Present** Polarity: negative Story-specific tag Definition: Penalty elements \(arsenic, antimony, etc.\) or refractory concerns noted in the release. Why it applies: While no refractory characteristics were identified, the report notes the presence of arsenic, tellurium, and bismuth in some composites, which will be assessed further. Evidence · text > Arsenic is highest in the Havilah fresh master composite \(741ppm As\)... Tellurium is low across the program except at Montague Boulder, where it correlates with bismuth \(R2 = 0.97\) and with leach residue gold grade \(R2 = 0.98\) ## Extracted facts Stored fact records: 13. Some facts used in scoring do not have a stored record. ## Metallurgical Results (13) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-0) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Montague Boulder Transitional - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 98.6 % - Recovery Basis: actual\_test - Head Grade: 1.93 - Head Grade Unit: g/t - Tailings Grade: 0.03 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.15 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: High CIL gold recovery of 98.6% for the Montague Boulder Transitional composite, well above the exceptional threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 98.6 Context: Montague Boulder Transitional #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 98.6% is at or above the exceptional band \(95%\) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-1) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Montague Boulder Fresh - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 91.1 % - Recovery Basis: actual\_test - Head Grade: 2.93 - Head Grade Unit: g/t - Tailings Grade: 0.2 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.14 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: Strong CIL gold recovery of 91.1% for the Montague Boulder Fresh composite, above the strong threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 91.1 Context: Montague Boulder Fresh #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-2) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Vanguard Oxide - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 98.5 % - Recovery Basis: actual\_test - Head Grade: 2.28 - Head Grade Unit: g/t - Tailings Grade: 0.09 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.14 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: High CIL gold recovery of 98.5% for the Vanguard Oxide composite, well above the exceptional threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 98.5 Context: Vanguard Oxide #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 98.5% is at or above the exceptional band \(95%\) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-3) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Vanguard Transitional - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 96.3 % - Recovery Basis: actual\_test - Head Grade: 2.02 - Head Grade Unit: g/t - Tailings Grade: 0.1 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.46 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: High CIL gold recovery of 96.3% for the Vanguard Transitional composite, well above the exceptional threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 96.3 Context: Vanguard Transitional #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 96.3% is at or above the exceptional band \(95%\) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-4) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Vanguard Fresh - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 95.8 % - Recovery Basis: actual\_test - Head Grade: 2.38 - Head Grade Unit: g/t - Tailings Grade: 0.12 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.27 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: High CIL gold recovery of 95.8% for the Vanguard Fresh composite, well above the exceptional threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 95.8 Context: Vanguard Fresh #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 95.8% is at or above the exceptional band \(95%\) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-5) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Havilah Fresh - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 89.7 % - Recovery Basis: actual\_test - Head Grade: 1.81 - Head Grade Unit: g/t - Tailings Grade: 0.18 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.3 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: Moderate CIL gold recovery of 89.7% for the Havilah Fresh composite, just below the strong threshold for CIL, but still within an economic range, supporting processing amenability despite elevated arsenic. - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 89.7 Context: Havilah Fresh #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-6) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Lord Nelson Fresh - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 92.9 % - Recovery Basis: actual\_test - Head Grade: 1.48 - Head Grade Unit: g/t - Tailings Grade: 0.18 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.3 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: Strong CIL gold recovery of 92.9% for the Lord Nelson Fresh composite, above the strong threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 92.9 Context: Lord Nelson Fresh #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-7) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Lord Henry Fresh - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 95.8 % - Recovery Basis: actual\_test - Head Grade: 1.07 - Head Grade Unit: g/t - Tailings Grade: 0.07 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.2 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: High CIL gold recovery of 95.8% for the Lord Henry Fresh composite, well above the exceptional threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 95.8 Context: Lord Henry Fresh #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 95.8% is at or above the exceptional band \(95%\) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-8) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Achilles Fresh - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 97.2 % - Recovery Basis: actual\_test - Head Grade: 1.44 - Head Grade Unit: g/t - Tailings Grade: 0.07 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.21 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: High CIL gold recovery of 97.2% for the Achilles Fresh composite, well above the exceptional threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 97.2 Context: Achilles Fresh #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 97.2% is at or above the exceptional band \(95%\) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-9) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Whistler Fresh - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 97.3 % - Recovery Basis: actual\_test - Head Grade: 2.1 - Head Grade Unit: g/t - Tailings Grade: 0.04 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.17 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: High CIL gold recovery of 97.3% for the Whistler Fresh composite, well above the exceptional threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 97.3 Context: Whistler Fresh #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 97.3% is at or above the exceptional band \(95%\) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-10) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Two Mile Hill Fresh \(MC1\) - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 95 % - Recovery Basis: actual\_test - Head Grade: 1.11 - Head Grade Unit: g/t - Tailings Grade: 0.09 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.14 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: High CIL gold recovery of 95.0% for the Two Mile Hill Fresh \(MC1\) composite, at the exceptional threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 95.0 Context: Two Mile Hill Fresh \(MC1\) #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 95% is at or above the exceptional band \(95%\) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-11) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Two Mile Hill Fresh \(MC2\) - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 99.3 % - Recovery Basis: actual\_test - Head Grade: 3.77 - Head Grade Unit: g/t - Tailings Grade: 0.08 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.13 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: Exceptional CIL gold recovery of 99.3% for the Two Mile Hill Fresh \(MC2\) composite, well above the exceptional threshold for CIL, strongly supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 99.3 Context: Two Mile Hill Fresh \(MC2\) #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 99.3% is at or above the exceptional band \(95%\) ### CIL [Link to this fact](https://atlas-staging.minestarters.com/news/btr-sandstone-pfs-metallurgy-delivers-94-gold-recovery--824cd9f5-c1dd-44fc-8762-4a84fc7c821a#fact-metallurgical-facts-12) Sandstone Gold Project · gold #### Identity - Project: Sandstone Gold Project - Commodity: gold - Region: australia\_wa - Reported Region: Western Australia - Ticker: BTR #### Test Work - Program Status: detailed - Test Type: CIL - Processing Route: conventional gravity and CIL flowsheet - Sample: Indomitable Oxide - Grind P80: 75 µm - Leach Time: 24 hours #### Recovery - Recovery: 96.7 % - Recovery Basis: actual\_test - Head Grade: 2.17 - Head Grade Unit: g/t - Tailings Grade: 0.06 - Tailings Grade Unit: g/t #### Reagents - Cyanide: 0.36 kg/t #### Lab - Laboratory: Metallurgy Pty Ltd and SGS Australia - Consultant: Independent Metallurgical Operations Pty Ltd and GR Engineering Services Limited #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2026-09-23T00:00:00.000Z Reasoning: High CIL gold recovery of 96.7% for the Indomitable Oxide composite, well above the exceptional threshold for CIL, supports the project's processing amenability. - Positive factor: High Recovery - Positive factor: Free Milling - Positive factor: Multi-Domain Tested - Positive factor: QP/CP Signed - Positive factor: JORC Compliant - Negative factor: Deleterious Elements Present Evidence · table > 96.7 Context: Indomitable Oxide #### 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 **Gravity Route** Polarity: neutral Definition: Gravity separation forms a material part of the flowsheet. Why it applies: processing\_route matches the gravity signal **High Recovery** Polarity: positive Definition: Recovery at or above the exceptional band for the commodity and processing route. Why it applies: 96.7% 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.