Reserves & Resources

Historical Reserves and Consolidated Grade at Limon and Libertad

B2Gold AIF 2010-2019 available on sedar.com and Calibre AIF 2020, available on sedar.com

Mineral Reserves at Limon and Libertad – December 31, 20201,2

  Category Tonnage
(kt)
Grade
(g/t Au)
Grade
(g/t Ag)
Contained Au
(koz)
Contained Ag
(koz)
Limon UG Probable 617 5.14 8.25 102 164
Limon OP Probable 3,389 4.24 1.22 462 133
Limon Stockpile Probable 29 3.82 0 4 0
Sub-total Limon Probable 4,036 4.38 2.29 568 297
             
Libertad UG Probable 477 3.92 20.00 60 307
Libertad OP Sources Probable 1,420 4.80 11.29 219 515
Libertad Stockpile Probable 55 9.30 0 16 0
Sub-total Libertad Probable 1,952 4.71 13.08 296 822
             
Total Mineral Reserves Probable 5,988 4.49 5.81 864 1,119

Note 1 -Limon Mineral Reserve Notes

  1. CIM (2014) definitions were followed for Mineral Reserves and rounded and reported in dry tonnes.
  2. Underground Mineral Reserves are estimated at fully costed and incremental cut-off grades of 3.3 g/t Au and 2.2 g/t Au, respectively, for Santa Pancha 1; 3.5 g/t Au and 2.2 g/t Au, respectively, for Panteon; and 2.6 g/t Au and 1.8 g/t Au, respectively, for Veta Nueva.
  3. Open pit Mineral Reserves are estimated at a cut-off grade of 1.24 g/t Au, and incorporate estimates of dilution and mining losses. 
  4. Mineral Reserves are estimated using an average long-term gold price of US$1,400 per ounce.
  5. A minimum mining width of 1.5 m was used for underground Mineral Reserves.
  6. Bulk density varies between 2.30 t/m3 and 2.41 t/m3 for all open pit Mineral Reserves; Bulk density varies between 2.47 t/m3 to 2.50 t/m3 for all underground Mineral Reserves.
  7. A mining extraction factor of 95% was applied to the underground stopes.  Where required a pillar factor was also applied for sill or crown pillar.  A 100% extraction factor was assumed for development.

Note 2 -Libertad Mineral Reserve Notes

  1. CIM (2014) definitions were followed for Mineral Reserves and rounded and reported in dry tonnes.
  2. Underground Mineral Reserves are estimated at fully costed and incremental cut-off grades of 3.05 g/t Au and 1.90 g/t Au, respectively, and incorporates 0.5 m dilution in both hanging wall and footwall.
  3. Open pit Mineral Reserves are estimated at a cut-off grade of 1.50 g/t Au for Pavon Norte and Pavon Central, and incorporate estimates of dilution and mining losses. 
  4. Open pit Mineral Reserves are estimated at a cut-off grade of 0.92 g/t Au for Jabali Antena, and incorporate estimates of dilution and mining losses. 
  5. Mineral Reserves are estimated using an average long-term gold price of US$1,400 per ounce.
  6. A minimum mining width of 1.5 m was used for underground Mineral Reserves.
  7. Open pit and underground bulk density varies from 1.70 t/m3 to 2.61 t/m3; underground backfill density is 1.00 t/m3.
  8. A mining extraction factor of 95% was applied to the underground stopes.  Where required a pillar factor was also applied for sill or crown pillar.  A 100% extraction factor was assumed for development.

Indicated & Inferred Mineral Resources at Limon and Libertad – December 31, 20203,4

  Category Tonnage
(kt)
Grade
(g/t Au)
Grade
(g/t Ag)
Contained Au
(koz)
Contained Ag
(koz)
Limon UG Indicated 1,475 5.46 5.40 259 256
Limon OP Indicated 4,393 4.45 1.57 628 222
Limon Stockpile Indicated 29 3.82 - 4 -
Tailings Indicated 7,329 1.12 - 263 -
Sub-total Limon Indicated 13,226 2.71 1.12 1,154 478
             
Libertad UG Indicated 421 5.72 28.15 77 381
Libertad OP Sources* Indicated 2,012 4.41 12.57 285 813
Libertad Stockpile Indicated 55 9.30 - 16 -
Sub-total Libertad Indicated 2,488 4.74 14.93 378 1,194
             
Total Mineral Resources Indicated 15,714 3.03 3.31 1,532 1,672
             
Limon UG Inferred 1,149 5.22 3.90 193 144
Limon OP Inferred 260 4.07 0.84 34 7
Sub-total Limon Inferred 1,409 5.01 3.33 227 151
             
Libertad UG Inferred 1,585 5.40 13.44 275 685
Libertad OP Sources* Inferred 1,246 2.77 5.37 111 215
Sub-total Libertad Inferred 2,831 4.24 9.89 386 900
             
Total Mineral Resources Inferred 4240 4.50 7.71 613 1,051

*Includes Pavon
Note 3 Limon Mineral Resource Notes

  1. Effective dates are December 31, 2020 for all El Limon deposits.
  2. CIM (2014) definitions were followed for Mineral Resources and numbers may not add up due to rounding.
  3. A cut-off grade of 1.15 g/t Au is used for Limon OP, 2.40 g/t for Limon UG, 3.05 g/t for SP1 UG, 2.25 g/t for SP2 UG, 2.41 g/t for Veta Nueva UG, 3.25 g/t for Panteon UG, 0.00 g/t for Tailings, and 2.60 g/t for Atravesada UG.
  4. Reporting shapes were used for reporting Limon UG, SP1 UG, Veta Nueva UG, Panteon UG, and Atravesada UG.
  5. Mineral Resources are estimated using a long-term gold price of US$1,500/oz Au in all deposits.
  6. Bulk density varies between 2.30 t/m3 and 2.50 t/m3.
  7. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
  8. Mineral Resources are inclusive of Mineral Reserves.

Note 4 – Libertad Mineral Resource Notes

  1. Effective dates are December 31, 2020 for all La Libertad deposits except San Antonio OP, with an effective date of August 30, 2020. The Pavon estimate has an effective date of November 12, 2019.
  2. CIM (2014) definitions were followed for Mineral Resources.
  3. A cut-off grade of 0.85 g/t Au is used for Jabali Antena OP, 0.81 g/t for Rosario OP, 0.80 g/t for Socorro OP and San Antonio OP, 2.90 g/t for San Juan UG, San Diego UG and Mojon UG, and 2.84 g/t for Jabali West UG and Jabali East UG, and 1.17 g/t Au for Pavon.
  4. Reporting shapes were used for reporting Jabali West UG.
  5. Mineral Resources are estimated using a long-term gold price of US$1,500/oz Au in all deposits except Pavón Sur, estimated using a long-term gold price of US$1,400/oz Au.
  6. Bulk density varies between 1.70 t/m3 and 2.57 t/m3.
  7. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
  8. Mineral Resources are inclusive of Mineral Reserves.
  9. Numbers may not add up due to rounding.

The Borosi Concession Projects

Overview; Calibre Mining Corp. has outlined mineral resources in the Borosi Concessions. (Click here for the Techncial Reports)

100% owned Eastern Borosi Project

INFERRED Mineral Resources – Eastern Borosi Project

CATEGORY METHOD /
VEIN
TONNAGE
(000 T)
GRADE AU
(G/T)
CONTAINED OUNCES
AU (OZ)
GRADE AG
(G/T)
CONTAINED OUNCES
AG (OZ)
GRADE AUEQ
(G/T)
CONTAINED OUNCES
AUEQ (OZ)
Inferred Underground              
  Blag 740 3.01 71,500 117 2,776,000 4.16 99,000
  East Dome 513 2.23 37,000 219 3,611,000 4.38 72,500
  Riscos 1,184 5.73 218,000 106 4,046,500 6.77 258,000
  Guapinol 612 12.74 251,000 12 243,500 12.86 253,000
  Vancouver 170 8.54 46,500 15 82,000 8.69 47,500
  Total Underground 3,219 6.03 624,000 104 10,758,500 7.05 729,500
     
Inferred Open Pit
  La Luna 1,199 1.98 76,500 16 601,000 2.13 82,000
     
Inferred Total Underground
and Open Pit
4,418 4.93 700,500 80 11,359,500 5.72 812,000

Notes:

  1. CIM (2014) definitions were followed for classification of Mineral Resources.
  2. Mineral Resources are estimated at a cut-off grade of 2.0 g/t AuEq for resources potentially mined by underground methods and 0.42 g/t AuEq for resources potentially mined by open pit methods.
  3. Gold equivalent values were calculated using the formula: AuEq (g/t) = Au (g/t) + Ag (g/t) / (101.8)
  4. Mineral Resources are estimated using a long-term gold price of US$1,500 per ounce of gold, US$23 per ounce of silver.
  5. A minimum mining width of 2.4 m was used for underground and 3 m for open pit.
  6. Bulk density is 2.65 t/m3 for Blag, East Dome, Riscos De Oro, and La Luna, and 2.60 t/m3 for Guapinol and Vancouver.
  7. East Dome is included in the Blag resource model and Vancouver is included in the Guapinol resource model.
  8. Numbers may not add due to rounding.
  9. Mineral Resources that are not Mineral Reserves do not have economic viability

100% owned Borosi Inferred Resources (Subject to an earn-in Agreement with Rio Tinto) (see news release here)

The Cerro Aeropuerto deposit contains gold and base metal bearing quartz veins and replacement style skarn mineralization.  The NI 43-101 compliant Inferred Mineral Resource estimate for the Cerro Aeropuerto deposit is provided in the table below:  

Cerro Aeropuerto NI 43-101 Inferred Mineral Resource (April 11, 2011)
Tonnes Grade
(Au g/t)
Grade
(Ag g/t)
Grade
(AuEq g/t)
Contained
Au (ounces)
Contained
Ag (ounces)
Contained
AuEq (ounces)
6,052,000 3.64 16.16 3.89 707,750 3,144,500 757,000
  1. CIM definition standards were followed for the resource estimate
  2. The 2011 resource models used Inverse Distance grade estimation within a three-dimensional block model with mineralized zones defined by wireframed solids and
  3. A base cutoff grade of 0.6 g/t AuEq was used for reporting mineral resources.
  4. Gold Equivalent (AuEq) grades were calculated using $1,058/oz Au for gold and $16.75/oz Ag for silver, and metallurgical recoveries and net smelter returns are assumed to be 100%.
  5. Resource Estimates for Cerro Aeropuerto are detailed in the technical report titled ‘NI 43-101 Technical Report and Resource Estimation of the Cerro Aeropuerto and La Luna Deposits, Borosi Concessions, Nicaragua’ by Todd McCracken, dated April 11, 2011.
  6. The quantity and grade of reported inferred resources in this estimation are uncertain in nature and there has been insufficient exploration to define these inferred resources as an indicated or measured mineral resource. It is uncertain if further exploration will result in upgrading them to an indicated or measured mineral resource category.
  7. Numbers may not add exactly due to rounding.
  8. Mineral Resources that are not mineral reserves do not have demonstrated economic viability.

100% owned Borosi Inferred Resources (Subject to an earn-in Agreement with Rio Tinto) (see news release here)

The NI 43-101 compliant Inferred Mineral Resource estimate for Primavera is provided in the table below:

Primavera NI 43-101 Inferred Mineral Resource (January 31, 2017)
Tonnes Grade
(Au g/t)
Grade
(Ag g/t)
Grade
(Cu %)
Grade
(AuEq g/t)
Contained
Au (ounces)
Contained
Ag (ounces)
Contained
Cu (pounds)
Contained
AuEq (ounces)
44,974,000 0.54 1.15 0.22 0.84 782,000 1,661,000 218,670,000 1,200,000
  1. CIM definition standards were followed for the resource estimate.
  2. The 2016 resource models used Ordinary Kriging grade estimation within a three-dimensional block model with mineralized zones defined by wireframed solids (HG=high grade, LG= low grade, sap=saprolite).
  3. A base cutoff grade of 0.5 g/t AuEq was used for reporting mineral resources.
  4. Gold Equivalent (AuEq) grades have been calculated using $1300/oz Au for gold, $2.40/lb for Copper, and $20.00/oz Ag for silver and metallurgical recoveries are assumed to be equal for all metals.
  5. Resource Estimates for the Primavera project are detailed in the NI 43-101 Technical Report titled ‘Primavera Project ‘by Todd McCracken, dated January 31, 2017.
  6. The quantity and grade of reported Inferred resources in this estimation are uncertain in nature and there has been insufficient exploration to define these Inferred resources as an indicated or measured resource. It is uncertain if further exploration will result in upgrading them to indicated or measure mineral resource category.
  7. Numbers may not add exactly due to rounding.
  8. Mineral Resources that are not mineral reserves do not have demonstrated economic viability.

Qualified Person

Darren Hall, MAusIMM, MSME, SVP & Chief Operating Officer Calibre Mining Corp is a “qualified person” as set out under NI 43-101 has reviewed and approved the scientific and technical information in this press release.


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