# ATAC Announces Updated Resource Estimate for the Osiris Deposit, Yukon Canonical Atlas analysis: https://atlas-extractions.minestarters.com/news/atac-announces-updated-resource-estimate-for-the-osiris-deposit-yukon--3e269513-fca0-461b-bcdc-c48301524ae2 Original source: https://money.tmx.com/en/quote/ATC/news/5779435500023434/atac-announces-updated-resource-estimate-for-the-osiris-deposit-yukon Publisher: tmx Original announcement: 2022-07-28T12:00:00.000Z Analysis by Minestarters Atlas Atlas analysis published: Unknown date Atlas analysis updated: Unknown date - Company: ATAC Resources Ltd. - Ticker: ATC - Exchange: TSX - Region: Yukon - Primary commodity: Gold - Secondary commodities: None reported - Document categories: Resource update, Metallurgy - Extracted: 2026-09-17 11:43:38 UTC Narrative sentiment: 0.70 · Bullish ## Minestarters Atlas summary ATAC Resources Ltd. has released an updated Mineral Resource Estimate for its Osiris Deposit in Yukon, reporting 732,000 Indicated ounces of gold at 4.12 g/t and 1,044,000 Inferred ounces of gold at 3.47 g/t. This update successfully converted 43% of the 2018 maiden Inferred Resource to the Indicated category, leading to an overall increase in contained gold ounces. Comprehensive metallurgical testwork confirmed viable processing paths for the refractory Carlin-style mineralization, with projected overall gold recoveries of 83% and up to 92% for specific methods. Reasoning: ATAC Resources announced an updated resource estimate for its Osiris Deposit, showing a significant upgrade of 43% of the 2018 Inferred resource to the Indicated category, increasing total contained gold ounces. Metallurgical testwork confirmed viable processing routes for the refractory Carlin-style mineralization with strong gold recoveries, although one route noted high acid consumption. The overall average grade of the total resource declined compared to the prior estimate. - Positive factor: Significant conversion of Inferred resources to Indicated category \(43%\) - Positive factor: Overall contained gold ounces increased from prior estimate - Positive factor: High-grade nature of the deposit \(Carlin-style\) - Positive factor: Viable processing paths confirmed with strong gold recoveries for refractory ore - Positive factor: Multiple zones remain open for extension - Negative factor: Overall average grade of the total resource decreased compared to the prior Inferred estimate - Negative factor: High acid consumption noted for one of the processing routes \(acid pressure oxidation\) - Negative factor: No specific effective date provided for the current resource estimate Low confidence — this extraction should be reviewed alongside the original source. Facts used in scoring: 7 ## Classification and evidence **Cut-off Disclosed** Polarity: positive Definition: Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison. Why it applies: A current resource fact retains the disclosed cut-off grade **Resource Update** Polarity: neutral Definition: Revised estimate for an existing resource — compare to prior to assess progress. Why it applies: The source explicitly discloses a revised resource estimate Evidence · text > Updated Resource Estimate **Mill Route** Polarity: neutral Definition: Processing via mill or concentrator \(CIL, CIP, tank leach, flotation\). Why it applies: the document describes a flotation route \("flotation"\) **POX/BIOX Route** Polarity: neutral Definition: Pressure or bio-oxidation for refractory ore — high CAPEX and OPEX. Why it applies: the document describes a pox\_biox route \("pressure oxidation"\) ## Extracted facts Stored fact records: 7. Some facts used in scoring do not have a stored record. ## Resource Estimates (6) ### indicated [Link to this fact](https://atlas-extractions.minestarters.com/news/atac-announces-updated-resource-estimate-for-the-osiris-deposit-yukon--3e269513-fca0-461b-bcdc-c48301524ae2#fact-resource-facts-0) Osiris Deposit, Rackla Gold Property · gold #### Identity - Project: Osiris Deposit, Rackla Gold Property - Commodity: gold - Region: canada\_yt - Reported Region: Yukon - Ticker: ATC #### Resource scope - Estimate type: resource - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Steven Ristorcelli - Resource group id: resource:594f226087668a88c5cd - Mining method: open\_pit - Ownership percent: 100 % #### Resource Data - Category: indicated - Tonnes: 4658000 - Grade: 604000 - Grade Unit: ounces - Contained Metal: 604000 - Contained Unit: oz - Cutoff Grade: 1 - Cutoff Unit: g/t #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2022-07-28T00:00:00.000Z Reasoning: This represents a substantial portion of the newly upgraded Indicated resource, with a strong grade for an open-pit scenario, contributing significantly to the overall resource confidence. - Positive factor: High-grade open-pit indicated resource - Positive factor: Contributes to significant category upgrade from prior estimate Evidence · table > 604,000 Context: 4,658,000 #### 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 ### indicated [Link to this fact](https://atlas-extractions.minestarters.com/news/atac-announces-updated-resource-estimate-for-the-osiris-deposit-yukon--3e269513-fca0-461b-bcdc-c48301524ae2#fact-resource-facts-1) Osiris Deposit, Rackla Gold Property · gold #### Identity - Project: Osiris Deposit, Rackla Gold Property - Commodity: gold - Region: canada\_yt - Reported Region: Yukon - Ticker: ATC #### Resource scope - Estimate type: resource - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Steven Ristorcelli - Resource group id: resource:07816c4e419bfd3202de - Mining method: underground - Ownership percent: 100 % #### Resource Data - Category: indicated - Tonnes: 870400 - Grade: 128000 - Grade Unit: ounces - Contained Metal: 128000 - Contained Unit: oz - Cutoff Grade: 2 - Cutoff Unit: g/t #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2022-07-28T00:00:00.000Z Reasoning: This high-grade underground indicated resource adds to the overall confidence and flexibility of the deposit, contributing to the significant category upgrade. - Positive factor: High-grade underground indicated resource - Positive factor: Contributes to significant category upgrade from prior estimate Evidence · table > 128,000 Context: 870,400 #### 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 ### indicated [Link to this fact](https://atlas-extractions.minestarters.com/news/atac-announces-updated-resource-estimate-for-the-osiris-deposit-yukon--3e269513-fca0-461b-bcdc-c48301524ae2#fact-resource-facts-2) Osiris Deposit, Rackla Gold Property · gold #### Identity - Project: Osiris Deposit, Rackla Gold Property - Commodity: gold - Region: canada\_yt - Reported Region: Yukon - Ticker: ATC #### Resource scope - Estimate type: resource - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Steven Ristorcelli - Resource group id: resource:68f2ff02fdc2e9bae864 - Mining method: combined - Ownership percent: 100 % #### Resource Data - Category: indicated - Tonnes: 5528400 - Grade: 732000 - Grade Unit: ounces - Contained Metal: 732000 - Contained Unit: oz #### Prior Estimate - Prior Tonnes: 12387077.51 - Prior Grade: 4.23 - Prior Contained Metal: 1685000 #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2022-07-28T00:00:00.000Z Reasoning: The conversion of a large portion of the prior Inferred resource to Indicated is a strong de-risking signal, significantly improving the confidence in the project's economics, despite a slight decrease in overall average grade. - Positive factor: Significant category upgrade \(43% of 2018 Inferred converted to Indicated\) - Positive factor: Substantial Indicated contained gold ounces - Positive factor: High average grade for a total resource - Negative factor: Overall average grade of the total resource \(Indicated + Inferred\) decreased compared to the prior Inferred estimate Evidence · table > 732,000 Context: 5,528,400 #### 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 **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 **Tonnage Decline** Polarity: negative Definition: Resource tonnage decreased vs prior estimate — pit optimization removed marginal material or geological model revised down. Why it applies: 5528400 against 12387077.51 previously **Grade Improvement** Polarity: positive Definition: Average resource grade improved vs prior estimate — better deposit economics. Why it applies: 732000 against 4.23 previously **Contained Metal Decline** Polarity: negative Definition: Contained metal decreased vs prior despite tonnage growth — grade dilution exceeds volume gain. Why it applies: 732000 against 1685000 previously **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 ### inferred [Link to this fact](https://atlas-extractions.minestarters.com/news/atac-announces-updated-resource-estimate-for-the-osiris-deposit-yukon--3e269513-fca0-461b-bcdc-c48301524ae2#fact-resource-facts-3) Osiris Deposit, Rackla Gold Property · gold #### Identity - Project: Osiris Deposit, Rackla Gold Property - Commodity: gold - Region: canada\_yt - Reported Region: Yukon - Ticker: ATC #### Resource scope - Estimate type: resource - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Steven Ristorcelli - Resource group id: resource:80de882fdc5484d951f2 - Mining method: open\_pit - Ownership percent: 100 % #### Resource Data - Category: inferred - Tonnes: 5370000 - Grade: 530000 - Grade Unit: ounces - Contained Metal: 530000 - Contained Unit: oz - Cutoff Grade: 1 - Cutoff Unit: g/t #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2022-07-28T00:00:00.000Z Reasoning: This inferred open-pit resource adds substantial ounces to the project's potential, maintaining a reasonable grade for future exploration and conversion. - Positive factor: Adds significant ounces to the overall resource base - Positive factor: Good grade for an open-pit inferred resource Evidence · table > 530,000 Context: 5,370,000 #### 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 ### inferred [Link to this fact](https://atlas-extractions.minestarters.com/news/atac-announces-updated-resource-estimate-for-the-osiris-deposit-yukon--3e269513-fca0-461b-bcdc-c48301524ae2#fact-resource-facts-4) Osiris Deposit, Rackla Gold Property · gold #### Identity - Project: Osiris Deposit, Rackla Gold Property - Commodity: gold - Region: canada\_yt - Reported Region: Yukon - Ticker: ATC #### Resource scope - Estimate type: resource - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Steven Ristorcelli - Resource group id: resource:2812e032cb07fd421e6e - Mining method: underground - Ownership percent: 100 % #### Resource Data - Category: inferred - Tonnes: 3990000 - Grade: 514000 - Grade Unit: ounces - Contained Metal: 514000 - Contained Unit: oz - Cutoff Grade: 2 - Cutoff Unit: g/t #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2022-07-28T00:00:00.000Z Reasoning: This inferred underground resource provides additional ounces at a good grade, indicating potential for future development and resource expansion. - Positive factor: Adds significant ounces to the overall resource base - Positive factor: Good grade for an underground inferred resource Evidence · table > 514,000 Context: 3,990,000 #### 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 ### inferred [Link to this fact](https://atlas-extractions.minestarters.com/news/atac-announces-updated-resource-estimate-for-the-osiris-deposit-yukon--3e269513-fca0-461b-bcdc-c48301524ae2#fact-resource-facts-5) Osiris Deposit, Rackla Gold Property · gold #### Identity - Project: Osiris Deposit, Rackla Gold Property - Commodity: gold - Region: canada\_yt - Reported Region: Yukon - Ticker: ATC #### Resource scope - Estimate type: resource - Reporting standards: ni\_43\_101 - QP Signed: Yes - Qualified person names: Steven Ristorcelli - Resource group id: resource:8601a69fa52305548aaf - Mining method: combined - Ownership percent: 100 % #### Resource Data - Category: inferred - Tonnes: 9360000 - Grade: 1044000 - Grade Unit: ounces - Contained Metal: 1044000 - Contained Unit: oz #### Prior Estimate - Prior Tonnes: 12387077.51 - Prior Grade: 4.23 - Prior Contained Metal: 1685000 #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2022-07-28T00:00:00.000Z Reasoning: The Inferred resource provides significant future potential, contributing to the overall contained metal growth, but the decrease in average grade compared to the prior estimate warrants attention. - Positive factor: Substantial Inferred contained gold ounces - Positive factor: Contributes to overall contained metal growth - Negative factor: Overall average grade of the total resource \(Indicated + Inferred\) decreased compared to the prior Inferred estimate Evidence · table > 1,044,000 Context: 9,360,000 #### 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 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 **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 **Tonnage Decline** Polarity: negative Definition: Resource tonnage decreased vs prior estimate — pit optimization removed marginal material or geological model revised down. Why it applies: 9360000 against 12387077.51 previously **Grade Improvement** Polarity: positive Definition: Average resource grade improved vs prior estimate — better deposit economics. Why it applies: 1044000 against 4.23 previously **Contained Metal Decline** Polarity: negative Definition: Contained metal decreased vs prior despite tonnage growth — grade dilution exceeds volume gain. Why it applies: 1044000 against 1685000 previously **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 ## Metallurgical Results (1) ### pressure oxidation [Link to this fact](https://atlas-extractions.minestarters.com/news/atac-announces-updated-resource-estimate-for-the-osiris-deposit-yukon--3e269513-fca0-461b-bcdc-c48301524ae2#fact-metallurgical-facts-6) Osiris Deposit, Rackla Gold Property · gold #### Identity - Project: Osiris Deposit, Rackla Gold Property - Commodity: gold - Region: canada\_yt - Reported Region: Yukon - Ticker: ATC #### Test Work - Program Status: detailed - Test Type: pressure oxidation - Processing Route: acid pressure oxidation and cyanidation #### Recovery - Recovery: 92 % - Recovery Basis: actual\_test #### Lab - Laboratory: Blue Coast Research - Consultant: Blue Coast Research #### Review - Needs Review: No - Historical: No #### Dates - Event date: 2022-07-28T00:00:00.000Z Reasoning: Achieving an exceptional 92% gold recovery with acid pressure oxidation is a strong technical result, but the high acid consumption due to carbonate content presents a potential economic challenge that needs optimization. - Positive factor: Exceptional recovery for refractory ore via acid pressure oxidation - Negative factor: High acid consumption due to elevated carbonate content Evidence · text > up to 92% recovery after cyanidation. However, the elevated carbonate content of the feed material incurs a high acid consumption. #### Tags used in scoring **POX/BIOX Route** Polarity: neutral Definition: Pressure or bio-oxidation for refractory ore — high CAPEX and OPEX. Why it applies: processing\_route matches the pox\_biox signal ## 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.