Star Royalties Highlights Copperstone Development Progress and Exploration Potential

Original announcement by tmx on

Company
Star Royalties Ltd.
Ticker
STRR
Exchange
TSX
Region
Arizona, USA
Primary commodity
Gold
Secondary commodities
Copper
Document categories
Resource update, Economic study, Permitting
Extracted
2026-09-19 01:15:48 UTC

Analysis by Minestarters Atlas

Minestarters Atlas analysis

Summary

Star Royalties highlights progress at the Copperstone Gold Mine, where a Preliminary Economic Assessment (PEA) shows an after-tax NPV5% of $227 million and an IRR of 171% at $3,000/oz gold. The project features a high-grade M&I resource of 1.2 Mt at 7.7 g/t Au and is being re-interpreted as an IOCG system, suggesting significant expansion potential.

Reasoning: The announcement highlights strong economic indicators from a PEA and significant resource scale, alongside a constructive new geological interpretation (IOCG) that suggests upside potential.

Positive factors

  • Robust PEA economics with 171% IRR
  • High-grade M&I resource (7.7 g/t Au)
  • IOCG geological interpretation suggests expansion potential
  • Permitting milestones on track for 2026 restart

Negative factors

  • Project restart depends on pending MPO amendments

Facts used in scoring: 3

Classification and evidence

High IRRpositive

Post-tax real unlevered IRR in the strong tier or better.

Why it applies: The PEA reports an after-tax IRR of 171%.

Evidence · text

“after-tax IRR of 171%”

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: The document reports 1.2 Mt at 7.7 g/t gold as Indicated.

Evidence · text

“1.2 Mt at 7.7 g/t”

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: The document reports 0.97 Mt at 6.3 g/t gold as Inferred.

Evidence · text

“0.97 Mt at 6.3 g/t”

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: The resource and PEA are referenced under NI 43-101 standards.

Evidence · text

“under National Instrument 43-101”

Extracted facts

Stored fact records: 2. Some facts used in scoring do not have a stored record.

Resource Estimates (2)

indicatedCopperstone · goldTonnes: 1200000Grade: 7.7Grade Unit: g/tContained Metal: 300000Contained Unit: ozView all details
Link to this fact

Identity

Project
Copperstone
Commodity
gold
Region
usa_az
Reported Region
Arizona, USA
Ticker
STRR

Resource scope

Estimate type
resource
Effective date
2025-02-06T00:00:00.000Z
Reporting standards
ni_43_101
Resource group id
resource:913e5d222208fae6763b
Mining method
underground

Resource Data

Category
indicated
Tonnes
1200000
Grade
7.7
Grade Unit
g/t
Contained Metal
300000
Contained Unit
oz

Prior Estimate

Resource Date
2025-02-06

Review

Needs Review
No
Historical
No

Dates

Event date
2025-11-07T00:00:00.000Z

Reasoning: High grade M&I resource reported.

Positive factors

  • High grade

Evidence · text

“300,000 oz of Measured and Indicated resources (1.2 Mt at 7.7 g/t)”

Tags used in scoring

Indicated Resourcepositive

Reasonable geological confidence based on adequate drilling; continuity can be assumed. Basis for Probable Reserves.

Why it applies: category is "indicated"

Cut-off Undisclosednegative

High-grade interval reported without stating the cut-off grade used for compositing.

Why it applies: no cutoff_grade was stated

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

inferredCopperstone · goldTonnes: 970000Grade: 6.3Grade Unit: g/tContained Metal: 197000Contained Unit: ozView all details
Link to this fact

Identity

Project
Copperstone
Commodity
gold
Region
usa_az
Reported Region
Arizona, USA
Ticker
STRR

Resource scope

Estimate type
resource
Effective date
2025-02-06T00:00:00.000Z
Reporting standards
ni_43_101
Resource group id
resource:e99a5a3c80bb214216a4
Mining method
underground

Resource Data

Category
inferred
Tonnes
970000
Grade
6.3
Grade Unit
g/t
Contained Metal
197000
Contained Unit
oz

Prior Estimate

Resource Date
2025-02-06

Review

Needs Review
No
Historical
No

Dates

Event date
2025-11-07T00:00:00.000Z

Reasoning: Inferred resource component.

Negative factors

  • Inferred category

Evidence · text

“197,000 oz of Inferred resources (0.97 Mt at 6.3 g/t)”

Tags used in scoring

Inferred Resourcenegative

Speculative category — limited drilling, geological continuity assumed but not confirmed. Cannot support economic studies alone.

Why it applies: category is "inferred"

Cut-off Undisclosednegative

High-grade interval reported without stating the cut-off grade used for compositing.

Why it applies: no cutoff_grade was stated

NI 43-101 Compliantpositive

Resource estimate prepared in compliance with NI 43-101 (Canada) — high reporting standard.

Why it applies: reporting_standards includes ni_43_101

PEA-Supportingneutral

Resource estimate prepared to support a Preliminary Economic Assessment — early-stage study.

Why it applies: the release names the study this estimate supports

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.