Pinnacle Receives More Positive Results from Second Round of Scoping Metallurgical Tests at El Potrero with Average Gold Recovery of 97.8% for the Main Dos de Mayo Vein

Original announcement by tmx on

Company
Pinnacle Silver and Gold Corp.
Ticker
PINN
Exchange
TSX
Region
Durango, Mexico
Primary commodity
Gold
Secondary commodities
Silver
Document categories
Metallurgy
Extracted
2026-09-12 18:38:07 UTC

Analysis by Minestarters Atlas

Minestarters Atlas analysis

Summary

Pinnacle Silver and Gold Corp. reported successful second-round scoping metallurgical tests at the El Potrero project in Mexico. Results showed exceptional gold recoveries averaging 97.8% for the Dos de Mayo vein via bottle roll leaching, while silver recoveries were more variable due to complex mineralogy.

Reasoning: Second round of scoping tests confirms very high gold recoveries (97.8%) and robust head grades, though silver mineralogy is more complex.

Positive factors

  • High gold recoveries (>97%)
  • Free-milling characteristics (electrum)
  • Low deleterious elements
  • Small grain size suggests predictable grind requirements

Negative factors

  • Silver recovery is variable and lower than gold
  • Gravity circuit showed no benefit and actually penalized silver recovery

Facts used in scoring: 8

Classification and evidence

Free Millingpositive

Simple, clean ore amenable to standard processing without oxidation.

Why it applies: Gold detected as electrum and high recoveries suggest simple metallurgy.

Evidence · text

“Gold in the form of electrum, a natural Au-Ag alloy, was detected in all seven samples.”

Bench Scale Onlynegative

Only preliminary bench tests completed — no locked-cycle or pilot work.

Why it applies: Tests were bottle roll and gravity tests on 1kg/25kg samples, which are bench-scale.

Evidence · text

“The bottle roll test was performed in a 2-gallon Nalgene bottle, using 1,000 g of sample”

Mill Routeneutral

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

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

Gravity Routeneutral

Gravity separation forms a material part of the flowsheet.

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

Multi-Domain Testedpositive

Variability across ore domains (oxide, transition, fresh) has been addressed.

Why it applies: 3 distinct composites were tested

Extracted facts

Stored fact records: 8. Some facts used in scoring do not have a stored record.

Metallurgical Results (8)

bottle rollEl Potrero · goldRecovery: 97.83 %View all details
Link to this fact

Identity

Project
El Potrero
Commodity
gold
Region
mexico
Reported Region
Durango, Mexico
Ticker
PINN

Test Work

Program Status
preliminary
Test Type
bottle roll
Processing Route
bottle roll cyanide leach
Sample
Dos de Mayo vein composite (5 samples), 53 micron grind
Grind P80
53 µm

Recovery

Recovery
97.83 %
Recovery Basis
actual_test

Lab

Laboratory
SGS

Review

Needs Review
No
Historical
No

Dates

Event date
2026-06-02T00:00:00.000Z

Reasoning: 97.83% recovery is exceptional for a preliminary scoping test.

Positive factors

  • Exceptional gold recovery

Evidence · text

“the five-sample composite from the bottle roll cyanide leach tests... resulted in a gold recovery of 97.83%”

Tags used in scoring

High Recoverypositive

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

Why it applies: 97.83% is at or above the exceptional band (95%)

bottle rollEl Potrero · silverRecovery: 70.02 %View all details
Link to this fact

Identity

Project
El Potrero
Commodity
silver
Region
mexico
Reported Region
Durango, Mexico
Ticker
PINN

Test Work

Program Status
preliminary
Test Type
bottle roll
Processing Route
bottle roll cyanide leach
Sample
Dos de Mayo vein composite (5 samples), 53 micron grind
Grind P80
53 µm

Recovery

Recovery
70.02 %
Recovery Basis
actual_test

Lab

Laboratory
SGS

Review

Needs Review
No
Historical
No

Dates

Event date
2026-06-02T00:00:00.000Z

Reasoning: Silver recovery is moderate and shows complexity compared to gold.

Positive factors

  • Improved recoveries compared to previous rounds

Negative factors

  • Variable and lower than gold

Evidence · text

“a silver recovery of 70.02%”

Tags used in scoring

Low Recoverynegative

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

Why it applies: 70.02% is below the weak band (75%)

bottle rollEl Potrero · goldRecovery: 96.79 %View all details
Link to this fact

Identity

Project
El Potrero
Commodity
gold
Region
mexico
Reported Region
Durango, Mexico
Ticker
PINN

Test Work

Program Status
preliminary
Test Type
bottle roll
Processing Route
bottle roll cyanide leach
Sample
Dos de Mayo vein composite (5 samples), 75 micron grind
Grind P80
75 µm

Recovery

Recovery
96.79 %
Recovery Basis
actual_test

Lab

Laboratory
SGS

Review

Needs Review
No
Historical
No

Dates

Event date
2026-06-02T00:00:00.000Z

Reasoning: High recovery even at a coarser grind.

Positive factors

  • High gold recovery

Evidence · text

“resulted in gold and silver recoveries of 96.79% and 66.38%, respectively”

Tags used in scoring

High Recoverypositive

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

Why it applies: 96.79% is at or above the exceptional band (95%)

bottle rollEl Potrero · silverRecovery: 66.38 %View all details
Link to this fact

Identity

Project
El Potrero
Commodity
silver
Region
mexico
Reported Region
Durango, Mexico
Ticker
PINN

Test Work

Program Status
preliminary
Test Type
bottle roll
Processing Route
bottle roll cyanide leach
Sample
Dos de Mayo vein composite (5 samples), 75 micron grind
Grind P80
75 µm

Recovery

Recovery
66.38 %
Recovery Basis
actual_test

Lab

Laboratory
SGS

Review

Needs Review
No
Historical
No

Dates

Event date
2026-06-02T00:00:00.000Z

Reasoning: Silver recovery is lower at 75 microns compared to 53 microns.

Negative factors

  • Lower recovery at coarser grind

Evidence · text

“resulted in gold and silver recoveries of 96.79% and 66.38%, respectively”

Tags used in scoring

Low Recoverynegative

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

Why it applies: 66.38% is below the weak band (75%)

bottle rollEl Potrero · goldRecovery: 97.6 %View all details
Link to this fact

Identity

Project
El Potrero
Commodity
gold
Region
mexico
Reported Region
Durango, Mexico
Ticker
PINN

Test Work

Program Status
preliminary
Test Type
bottle roll
Processing Route
bottle roll cyanide leach
Sample
La Estrella vein sample

Recovery

Recovery
97.6 %
Recovery Basis
actual_test

Lab

Laboratory
SGS

Review

Needs Review
No
Historical
No

Dates

Event date
2026-06-02T00:00:00.000Z

Reasoning: Consistent high gold recovery across different veins.

Positive factors

  • High gold recovery

Evidence · text

“gold recoveries of 97.6%... were obtained for the Estrella... veins”

Tags used in scoring

High Recoverypositive

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

Why it applies: 97.6% is at or above the exceptional band (95%)

bottle rollEl Potrero · silverRecovery: 64.7 %View all details
Link to this fact

Identity

Project
El Potrero
Commodity
silver
Region
mexico
Reported Region
Durango, Mexico
Ticker
PINN

Test Work

Program Status
preliminary
Test Type
bottle roll
Processing Route
bottle roll cyanide leach
Sample
La Estrella vein sample

Recovery

Recovery
64.7 %
Recovery Basis
actual_test

Lab

Laboratory
SGS

Review

Needs Review
No
Historical
No

Dates

Event date
2026-06-02T00:00:00.000Z

Reasoning: Silver recovery is lower and more variable than gold.

Negative factors

  • Variable silver recovery

Evidence · text

“silver recoveries were more variable, at... 64.7%... for La Estrella”

Tags used in scoring

Low Recoverynegative

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

Why it applies: 64.7% is below the weak band (75%)

bottle rollEl Potrero · goldRecovery: 97.4 %View all details
Link to this fact

Identity

Project
El Potrero
Commodity
gold
Region
mexico
Reported Region
Durango, Mexico
Ticker
PINN

Test Work

Program Status
preliminary
Test Type
bottle roll
Processing Route
bottle roll cyanide leach
Sample
El Capulin vein sample

Recovery

Recovery
97.4 %
Recovery Basis
actual_test

Lab

Laboratory
SGS

Review

Needs Review
No
Historical
No

Dates

Event date
2026-06-02T00:00:00.000Z

Reasoning: Consistent high gold recovery.

Positive factors

  • High gold recovery

Evidence · text

“gold recoveries of... 97.4% were obtained for the... Capulin... veins”

Tags used in scoring

High Recoverypositive

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

Why it applies: 97.4% is at or above the exceptional band (95%)

bottle rollEl Potrero · silverRecovery: 80.5 %View all details
Link to this fact

Identity

Project
El Potrero
Commodity
silver
Region
mexico
Reported Region
Durango, Mexico
Ticker
PINN

Test Work

Program Status
preliminary
Test Type
bottle roll
Processing Route
bottle roll cyanide leach
Sample
El Capulin vein sample

Recovery

Recovery
80.5 %
Recovery Basis
actual_test

Lab

Laboratory
SGS

Review

Needs Review
No
Historical
No

Dates

Event date
2026-06-02T00:00:00.000Z

Reasoning: Silver recovery in El Capulin is better than in the other tested veins.

Positive factors

  • Relatively high silver recovery compared to other veins

Evidence · text

“silver recoveries... at... 80.5%, respectively, reflecting the more complex silver mineralogy”

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.