Stuhini Reports Strong Metallurgical Recoveries from Surface Mini-Bulk Sample at Silver Surprise Zone, Ruby Creek Project

Original announcement by tmx on

Company
Stuhini Exploration Ltd.
Ticker
STU
Exchange
TSX
Region
British Columbia
Primary commodity
Silver
Secondary commodities
Molybdenum
Document categories
Metallurgy
Extracted
2026-09-14 15:16:26 UTC

Analysis by Minestarters Atlas

Minestarters Atlas analysis

Summary

Stuhini Exploration has reported highly favourable metallurgical results from a 719 kg surface mini-bulk sample at the Silver Surprise Zone of the Ruby Creek Project. Direct smelting achieved a 95% silver recovery from a 4,200 g/t silver feed, while gravity separation successfully produced a refined silver bar.

Reasoning: The results demonstrate exceptionally high silver recovery (95%) from an ultra-high-grade surface sample using a low-complexity smelting route, significantly de-risking the processing of the Silver Surprise Zone.

Positive factors

  • High silver recovery (95%) via simple direct smelting
  • Very high head grade (4,200 g/t Ag)
  • Simple, low-complexity processing route identified
  • Gravity separation successfully produced a refined silver bar

Negative factors

  • Test scale is a mini-bulk sample (719 kg), which may not be fully representative of the deposit

Facts used in scoring: 3

Classification and evidence

Free Millingpositive

Simple, clean ore amenable to standard processing without oxidation.

Why it applies: The release notes that the high native silver content and simple mineralogy make it well-suited to low-complexity processing.

Evidence · text

“The high native silver content and simple quartz-hosted mineralogy make the mineralization particularly well-suited to this low-complexity processing route.”

Mill Routeneutral

Processing via mill or concentrator (CIL, CIP, tank leach, flotation).

Why it applies: The sample was processed using a Denver ball mill.

Evidence · text

“The sample was milled in a 3' x 3' Denver ball mill”

Gravity Routeneutral

Gravity separation forms a material part of the flowsheet.

Why it applies: the document describes a gravity route ("gravity")

Single Domain Onlynegative

Testing limited to one composite or domain — representativeness not established.

Why it applies: only one composite was tested

Extracted facts

Stored fact records: 3. Some facts used in scoring do not have a stored record.

Metallurgical Results (3)

direct smeltingRuby Creek Project · silverRecovery: 95 %Head Grade: 4200Head Grade Unit: g/tView all details
Link to this fact

Identity

Project
Ruby Creek Project
Commodity
silver
Region
canada_bc
Reported Region
British Columbia
Ticker
STU

Test Work

Program Status
preliminary
Test Type
direct smelting
Processing Route
direct smelting
Sample
719 kg surface mini-bulk sample from Silver Surprise Zone

Recovery

Recovery
95 %
Recovery Basis
actual_test
Head Grade
4200
Head Grade Unit
g/t

Lab

Consultant
Rino Mihoc of Ruby Gold Ltd.

Review

Needs Review
No
Historical
No

Dates

Event date
2025-12-01T00:00:00.000Z

Reasoning: 95% recovery from ultra-high-grade material via direct smelting is a standout outcome.

Positive factors

  • 95% recovery is exceptional for direct smelting

Negative factors

  • Small sample size

Evidence · text

“Direct smelting test achieved 95% silver recovery”

Tags used in scoring

High Recoverypositive

Recovery at or above the exceptional band for the commodity and processing route.

Why it applies: 95% is at or above the exceptional band (90%)

gravityRuby Creek Project · silverRecovery: 15 %Head Grade: 4200Head Grade Unit: g/tView all details
Link to this fact

Identity

Project
Ruby Creek Project
Commodity
silver
Region
canada_bc
Reported Region
British Columbia
Ticker
STU

Test Work

Program Status
preliminary
Test Type
gravity
Processing Route
gravity separation using a Gemini shaking table
Sample
719 kg surface mini-bulk sample from Silver Surprise Zone (gravity circuit)

Recovery

Recovery
15 %
Recovery Basis
actual_test
Head Grade
4200
Head Grade Unit
g/t
Conc. Grade
10
Conc. Grade Unit
%

Review

Needs Review
No
Historical
No

Dates

Event date
2025-12-01T00:00:00.000Z

Reasoning: While gravity recovery is low (15%), it successfully concentrated the silver for subsequent smelting and confirmed the presence of free, heavy silver.

Positive factors

  • Successfully produced a refined silver bar
  • Simple single-pass process

Negative factors

  • Low recovery (15%) for the gravity circuit alone

Evidence · text

“Gravity separation using a single pass on a Gemini shaking table recovered 15% of the contained silver”

Tags used in scoring

Gravity Routeneutral

Gravity separation forms a material part of the flowsheet.

Why it applies: processing_route matches the gravity signal

Low Recoverynegative

Recovery below the weak band for the commodity and processing route.

Why it applies: 15% is below the weak band (75%)

Fact 3Ruby Creek Project · silverHead Grade: 4200Head Grade Unit: g/tView all details
Link to this fact

Identity

Project
Ruby Creek Project
Commodity
silver
Region
canada_bc
Reported Region
British Columbia
Ticker
STU

Test Work

Sample
719 kg surface mini-bulk sample from Silver Surprise Zone (gravity tailings)

Recovery

Head Grade
4200
Head Grade Unit
g/t
Tailings Grade
3540
Tailings Grade Unit
g/t

Review

Needs Review
No
Historical
No

Dates

Event date
2025-12-01T00:00:00.000Z

Reasoning: Tailings grade of 3,540 g/t silver confirms the gravity stage is not efficient for primary recovery, necessitating the smelting route.

Negative factors

  • High tailings grade indicates significant silver loss in the gravity stage

Evidence · text

“Tailings after gravity separation assayed 3,540 g/t silver”

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.