Great Panther Announces Updated Mineral Reserve and Mineral Resource Estimates for the Tucano Gold Mine

Original announcement by tmx on

Company
Great Panther Mining Limited
Ticker
GPR
Exchange
TSX
Region
Brazil
Primary commodity
Gold
Secondary commodities
None reported
Document categories
Resource update, Other
Extracted
2026-09-16 03:29:32 UTC

Analysis by Minestarters Atlas

Minestarters Atlas analysis

Summary

Great Panther has released updated 2021 Mineral Reserve and Mineral Resource Estimates for the Tucano Gold Mine in Brazil. The update highlights a 24% increase in open pit reserves and a 65% increase in open pit Measured and Indicated resources compared to the 2020 estimate.

Reasoning: The update shows significant growth in both open pit reserves and M&I resources, effectively extending mine life and replacing depletion.

Positive factors

  • Significant tonnage growth in open pit reserves (+24%)
  • Substantial M&I resource expansion (+65%)
  • Successful replacement of mining depletion
  • Increased mine life for open pit

Negative factors

  • Underground estimates pending engineering studies

Facts used in scoring: 5

Classification and evidence

Tonnage Growthpositive

Tonnage increase reaching the strong tier vs prior estimate, with grade maintained or improved.

Why it applies: Open pit reserves increased by 24% since the 2020 MRMR.

Evidence · text

“a 24% increase in P&P open pit reserves since the previously reported MRMR estimate”

NI 43-101 Compliantpositive

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

Why it applies: Estimates were prepared in accordance with NI 43-101 standards.

Evidence · text

“prepared in accordance with National Instrument 43-101”

QA/QC Disclosedpositive · Story-specific tag

Release includes QA/QC disclosure — certified lab, QP sign-off, or stated methods (blanks, standards, duplicates).

Why it applies: Release details QA/QC protocols including blanks, standards, duplicates, and certified laboratory use.

Evidence · text

“includes the regular insertion of blanks, standards and duplicates”

Extracted facts

Stored fact records: 5. Some facts used in scoring do not have a stored record.

Resource Estimates (5)

provenTucano Gold Mine · goldTonnes: 2495000Grade: 1.4Grade Unit: g/tContained Metal: 112000Contained Unit: ozView all details
Link to this fact

Identity

Project
Tucano Gold Mine
Commodity
gold
Region
brazil
Reported Region
Brazil
Ticker
GPR

Resource scope

Estimate type
reserve
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Fernando A. Cornejo, Nicholas Winer, Carlos Pires
Resource group id
resource:5ec471fb40da2ba3cda5
Deposit or zone
Open pit
Mining method
combined
Material type
oxide

Resource Data

Category
proven
Tonnes
2495000
Grade
1.4
Grade Unit
g/t
Contained Metal
112000
Contained Unit
oz
Cutoff Grade
2.4
Cutoff Unit
g/t

Prior Estimate

Resource Date
2021-07-31

Review

Needs Review
No
Historical
No

Dates

Event date
2022-04-26T00:00:00.000Z

Reasoning: Proven reserve component of the open pit.

Evidence · table

“1.40”

Context: 2,495

Tags used in scoring

Proven Reservepositive

Measured Resource with demonstrated economic viability after applying modifying factors.

Why it applies: category is "proven"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

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 Compliantpositive

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

Why it applies: reporting_standards includes ni_43_101

probableTucano Gold Mine · goldTonnes: 74371000Grade: 1.08Grade Unit: g/tContained Metal: 259000Contained Unit: ozView all details
Link to this fact

Identity

Project
Tucano Gold Mine
Commodity
gold
Region
brazil
Reported Region
Brazil
Ticker
GPR

Resource scope

Estimate type
reserve
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Fernando A. Cornejo, Nicholas Winer, Carlos Pires
Resource group id
resource:6ef8c4b4fffcf328071d
Deposit or zone
Open pit
Mining method
combined
Material type
oxide

Resource Data

Category
probable
Tonnes
74371000
Grade
1.08
Grade Unit
g/t
Contained Metal
259000
Contained Unit
oz
Cutoff Grade
2.4
Cutoff Unit
g/t

Prior Estimate

Resource Date
2021-07-31

Review

Needs Review
No
Historical
No

Dates

Event date
2022-04-26T00:00:00.000Z

Reasoning: Probable reserve component of the open pit.

Evidence · table

“1.08”

Context: 7,4371

Tags used in scoring

Probable Reservepositive

Indicated Resource with demonstrated economic viability after applying modifying factors.

Why it applies: category is "probable"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

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 Compliantpositive

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

Why it applies: reporting_standards includes ni_43_101

measuredTucano Gold Mine · goldTonnes: 5651000Grade: 1.2Grade Unit: g/tContained Metal: 217000Contained Unit: ozView all details
Link to this fact

Identity

Project
Tucano Gold Mine
Commodity
gold
Region
brazil
Reported Region
Brazil
Ticker
GPR

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Fernando A. Cornejo, Nicholas Winer, Carlos Pires
Resource group id
resource:86250ea51833a37112f6
Deposit or zone
Open pit
Mining method
combined
Material type
oxide

Resource Data

Category
measured
Tonnes
5651000
Grade
1.2
Grade Unit
g/t
Contained Metal
217000
Contained Unit
oz
Cutoff Grade
2.4
Cutoff Unit
g/t

Prior Estimate

Resource Date
2021-07-31

Review

Needs Review
No
Historical
No

Dates

Event date
2022-04-26T00:00:00.000Z

Reasoning: Measured resource component of the open pit.

Evidence · table

“1.20”

Context: 5,651

Tags used in scoring

Measured Resourcepositive

Highest confidence category — tonnage, grade, shape well-established from closely-spaced drilling. Basis for Proven Reserves.

Why it applies: category is "measured"

Cut-off Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

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 Compliantpositive

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

Why it applies: reporting_standards includes ni_43_101

indicatedTucano Gold Mine · goldTonnes: 18863000Grade: 1.17Grade Unit: g/tContained Metal: 711000Contained Unit: ozView all details
Link to this fact

Identity

Project
Tucano Gold Mine
Commodity
gold
Region
brazil
Reported Region
Brazil
Ticker
GPR

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Fernando A. Cornejo, Nicholas Winer, Carlos Pires
Resource group id
resource:219d2925d0919ccb70a6
Deposit or zone
Open pit
Mining method
combined
Material type
oxide

Resource Data

Category
indicated
Tonnes
18863000
Grade
1.17
Grade Unit
g/t
Contained Metal
711000
Contained Unit
oz
Cutoff Grade
2.4
Cutoff Unit
g/t

Prior Estimate

Resource Date
2021-07-31

Review

Needs Review
No
Historical
No

Dates

Event date
2022-04-26T00:00:00.000Z

Reasoning: Indicated resource component of the open pit.

Evidence · table

“1.17”

Context: 18,863

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 Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

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 Compliantpositive

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

Why it applies: reporting_standards includes ni_43_101

inferredTucano Gold Mine · goldTonnes: 1476000Grade: 1.1Grade Unit: g/tContained Metal: 52000Contained Unit: ozView all details
Link to this fact

Identity

Project
Tucano Gold Mine
Commodity
gold
Region
brazil
Reported Region
Brazil
Ticker
GPR

Resource scope

Estimate type
resource
Reporting standards
ni_43_101
QP Signed
Yes
Qualified person names
Fernando A. Cornejo, Nicholas Winer, Carlos Pires
Resource group id
resource:11ec334eb8e0028d3517
Deposit or zone
Open pit
Mining method
combined
Material type
oxide

Resource Data

Category
inferred
Tonnes
1476000
Grade
1.1
Grade Unit
g/t
Contained Metal
52000
Contained Unit
oz
Cutoff Grade
2.4
Cutoff Unit
g/t

Prior Estimate

Resource Date
2021-07-31

Review

Needs Review
No
Historical
No

Dates

Event date
2022-04-26T00:00:00.000Z

Reasoning: Inferred resource component of the open pit.

Negative factors

  • Inferred category implies limited geological confidence

Evidence · table

“1.10”

Context: 1,476

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 Disclosedpositive

Cut-off grade used for resource reporting is clearly stated, enabling like-for-like comparison.

Why it applies: cutoff_grade is stated

QP/CP Signedpositive

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 Compliantpositive

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

Why it applies: reporting_standards includes ni_43_101

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.