Guanajuato Mine Complex Resource Estimates

Summary Table of the Updated 2019 Mineral Resource Estimate for the Guanajuato Mine Complex¹

MEASURED
Mine Tonnes Ag (g/t) Au (g/t) Pb (%) Zn (%) Ag
(oz)
Au
(oz)
Ag Eq Oz
San Ignacio 314,863 156 3.06 - - 1,574,848 30,984 4,053,537
Guanajuato 256,260 206 1.72 - - 1,693,799 14,131 2,824,256
Total Measured  571,123 178 2.46 - - 3,268,647 45,115 6,877,793
                 
INDICATED
Mine Tonnes Ag (g/t) Au (g/t) Pb (%) Zn (%) Ag (oz) Au (oz) Ag Eq Oz
San Ignacio 71,554 173 2.87 - - 398,172 6,613 927,201
Guanajuato 87,476 199 1.62 - - 560,673 4,553 924,903
Total Indicated    159,030 188 2.18 - - 958,845 11,166 1,852,104
                 
MEASURED & INDICATED
Mine Tonnes Ag (g/t) Au (g/t) Pb (%) Zn (%) Ag (oz) Au (oz) Ag Eq Oz
San Ignacio 386,417 159 3.03 - - 1,973,020 37,597 4,980,738
Guanajuato 343,736 204 1.69 - - 2,254,472 18,684 3,749,160
Total M&I 730,153 180 2.40 - - 4,227,492 56,281 8,729,897
                 
INFERRED
Mine Tonnes Ag (g/t) Au (g/t) Pb (%) Zn (%) Ag (oz) Au (oz) Ag Eq Oz
San Ignacio 501,870 149 2.69 - - 2,405,484 43,398 5,877,391
Guanajuato 208,609 168 2.32 - - 1,129,416 15,561 2,374,341
El Horcón  162,140 76 3.44 2.69 3.79 398,094 17,942 2,092,913
Total Inferred  872,619 140 2.74 - - 3,932,994 76,901 4,467,254

1Mineral Resource Estimates use an effective date of July 31, 2019 for San Ignacio and Guanajuato and used a metal price outlook of US$15.80/oz silver and US$1,290/oz gold.  Mineral Resource Estiamtes for El Horcon use an effective date of August 31, 2016 and used a metal price outlook of US$18.00/oz silver, US$1,300/oz gold, and US$0.80/lb lead.

Notes for San Ignacio Mine Mineral Resource Estimate:

  1. Ven Bulk Density of 2.64t/m³.
  2. Measured, Indicated and Inferred Mineral Resources are reported at a full cost cut-off Net Smelter Return (NSR) of US$100/tonne.
  3. Totals may not agree due to rounding.
  4. Grades in metric units and contained silver and gold in troy ounces.
  5. Minimum true width 0.5m.
  6. Mineral Resources are estimated using metal prices of US$15.80/oz Ag and US$1,290/oz Au (based on 3 year back averages); and metallurgical recoveries of 88% Ag, 87% Au.
  7. 2019 Mineral Resources Ag Eq oz were calculauted using 80:1 Ag:Au ratio.  The ratios are refelctive of average metal prices for 2019.

Notes for Guanajuato Mine Mineral Resource Estimate:

  1. Cut-offs are based on the marginal operating costs per mining area being US$113/tonne for Cata, US$75/tonne for Santa Margarita / San Cayetano, US$77/tonne for Los Pozos, US$124/tonne for Guanajuatito, US$60/tonne for Promontorio, and US$197/tonne for Valenciana.
  2. Block model grades converted to US$/t value using process plant recoveries of 88% Ag, 87% Au, and net smelter terms negotiated for pyrite concentrates.
  3. Rock Density for all veins is 2.68t/m³.
  4. Totals may not agree due to rounding.
  5. Grades in metric units.
  6. Contained silver and gold in troy ounces.
  7. Minimum true width 1.0m.
  8. Ag:Au ratio of 80:1 was used for Ag eq (oz)

Notes for El Horcón Project Mineral Resource Estimate:

  1. US$110 per tonne Cut-off, considering plant recoveries of %Ag, %Au, %Pb, and net smelter terms typical for Pb concentrates.
  2. Rock Density for all veins for Diamantillo is 2.77t/m³, San Guillermo 2.78t/m³, Diamantillo HW is 2.62t/m³, Natividad 2.57t/m³.
  3. Totals may not agree due to rounding.
  4. Grades in metric units.
  5. Contained silver and gold in troy ounces.
  6. Minimum true width 1.5m
  7. Metal Prices US$18.00/oz silver, US$1,300/oz gold, and US$0.80/lb lead.
  8. Silver equivalent calculations for El Horcón include gold and lead content but not zinc, as the zinc would not be recovered in the Guanajuato plant.
  9. Report effective date of August 31, 2016.

The technical information for the Guanajuato Mine and the San Ignacio Mine in this news release has been reviewed and approved by the Company’s employees Robert F. Brown, P. Eng., and Mohammad Nourpour, P. Geo., who are the Qualified Persons for GMC under the meaning of NI 43-101.  Aspects relating to mining and metallurgy are overseen by Neil Hepworth, C. Eng. and COO for Great Panther.

Analyses from the Guanajuato and San Ignacio Mines’ underground sampling, operational and exploration drilling are completed at the Company’s GMC laboratory.  Exploration drill core is re-assayed by SGS in Durango, Mexico.

The Company’s QA/QC program for drill-core includes the regular insertion of blanks, standards, and duplicates into the sample shipments, diligent monitoring of assay results, and necessary remedial actions.  The GMC laboratory was independently run and certified by SGS until December 2018 and used the following analytical techniques: ASS12B for silver with over-limits (300 g/t) completed by FAG323; FAA313 for gold with over-limits completed by FAG323; and lead, zinc, copper, arsenic and antimony analyses completed using atomic absorption spectroscopy (“AAS”). 

Since the beginning of 2019 the GMC laboratory has been managed by qualified Company personnel and uses the same analytical techniques as under the previous SGS management.  QA/QC monitoring of the GMC laboratory includes shipping all exploration drill hole pulps to SGS-DGO for re-analysis.  Statistical comparison using correlation coefficients shows excellent correlations in both gold and silver.

 

Topia Resource Estimates

Summary Table of the Updated 2018 Mineral Resource Estimate for the Topia Mine

MEASURED
Mine Tonnes Ag
(g/t)
Au
(g/t)
Pb
(%)
Zn
(%)
Ag
(oz)
Au
(oz)
Ag Eq Oz
Topia 310,600 474 1.36 4.02 4.20 4,732,807 13,579 9,920,000
               
INDICATED
Mine Tonnes Ag
(g/t)
Au
(g/t)
Pb
(%)
Zn
(%)
Ag
(oz)
Au
(oz)
Ag Eq Oz
Topia 165,300 436 1.34 3.57 3.79 2,317,563 7,123 4,850,000
               
MEASURED & INDICATED
Mine Tonnes Ag
(g/t)
Au
(g/t)
Pb
(%)
Zn
(%)
Ag
(oz)
Au
(oz)
Ag Eq Oz
Topia 475,900 461 1.35   3.87 4.06 7,050,370 20,702 14,770,000
               
INFERRED
Mine Tonnes Ag
(g/t)
Au
(g/t)
Pb
(%)
Zn
(%)
Ag
(oz)
Au
(oz)
Ag Eq Oz
Topia 400,400 434 1.34 2.86 2.97 5,586,431 17,248 10,720,000

Notes:

  1. 2018 Mineral Resource Ag eq oz were calculated using 80:1 Ag:Au ratio, and ratios of 1:0.0636 and 1:0.0818 for the price/ounce of silver to price/pound of lead and zinc, respectively. The ratios are reflective of average metal prices for 2018.
  2. CIM Definitions were followed for Mineral Resources.
  3. Area-Specific vein bulk densities as follows: Argentina - 3.06t/m3; 1522 - 3.26t/m3; Durangueno - 3.12t/m3; El Rosario - 3.00t/m3; Hormiguera - 2.56t/m3; La Prieta - 2.85t/m3; Recompensa - 3.30t/m3; Animas - 3.02t/m3; San Miguel - 2.56t/m3.
  4. Measured, Indicated, and Inferred Mineral Resources are reported at a cut-off Net Smelter Return (NSR) as follows: 1522 Mine US$193/t, Argentina Mine US$172/t, Durangueno Mine US$144/t, Recompensa Mine US$151/t, Hormiguera Mine US$152/t, El Rosario Mine US$173/t, La Prieta US$235/t, Animas US$149/t, and San Miguel US$248/t.
  5. Totals may not agree due to rounding.
  6. A minimum mining width of 0.30 metres was used.
  7. Mineral Resources are estimated using metal prices of US$1,225/oz Au, US$15.50/oz Ag, US$1.00/lb Pb, and US$1.15/lb Zn; and metallurgical recoveries of 94% for Ag, 60% for Au, 94% for Pb, and 93% for Zn.

The geological interpretations are similar to the previously reported MRE with the exception of adjustments made due to improved geological understanding of faulting and vein splays, and further constraints on the Leapfrog geological software used to create wireframes. Vein widths were adjusted to a minimum width of 0.3 m, with the assumption of zero grade waste, for the construction of wireframes. Capping of extraordinary high analytical values was completed both for drill core and underground samples from all 52 veins. The block modelling was conducted using MicroMine 3D geological software and the Inverse Distance Cubed grade estimation method. The NSR calculation was then completed on undiluted and capped block model assays.

Over the period of November 30, 2014 to July 31, 2018 (effective dates of the last and this MRE, respectively) a total of 221.6 kt was mined at Topia with average grades of 357 g/t silver, 0.67 g/t gold, 2.27% lead, and 3.03% zinc. Reconciliations were completed at four of the nine mining areas (Argentina, Recompensa, Hormiguera, and El Rosario) to see how well production from each area matched block model corresponding volumes mined and associated grades. The four areas reconciled in this MRE show reasonable agreement with production in terms of tonnes and associated grades.

While most of the current MRE is derived from Company core drilling and underground sampling along mine development, certain portions of the MRE (i.e. parts of Argentina Mine) are derived from verified pre-existing underground sampling. Analysis of the underground mine samples was completed at the on-site Topia Mine laboratory, while analysis of the drill-core was independently performed at the Company’s Guanajuato Mine Complex (“GMC”) laboratory by SGS Minerals Services (ISO 17025 Certified).

The Company’s QA/QC program for drill-core includes the regular insertion of blanks, standards, and duplicates into the sample shipments, diligent monitoring of assay results, and necessary remedial actions. QA/QC monitoring of the Topia Mine laboratory was accomplished by the monthly shipping and re-analysis of 25-30 mine sample pulps to the GMC laboratory, and statistically comparing the two laboratories’ results using correlation coefficients. The GMC laboratory used the following analytical techniques, ASS12B for silver with over-limits (300 g/t) completed by FAG323, FAA313 for gold with over-limits completed by FAG323, and lead, zinc, copper, arsenic and antimony analysis completed using atomic absorption spectroscopy (“AAS”). At the Topia Mine laboratory, silver, gold, lead, zinc, and iron analysis are completed using AAS. Silver (300 g/t) and gold (10 g/t) over-limits are completed by fire assay.

Robert F. Brown, P. Eng. was designated as the Qualified Person by Great Panther for the Topia Mine under the meaning of National Instrument 43-101.

Coricancha Resource Estimates

Updated 2017 Mineral Resource Estimate for the Coricancha Mine, Peru

MEASURED
Mine Tonnes Au
(g/t)
Ag
(g/t)
Pb
(%)
Zn
(%)
Cu
(%)
Ag eq gpt Ag eq oz
(M)
Constancia 270,336 6.2 219 2.36 3.44 0.43 1,064 9.24
Wellington 92,328 6.1 184 1.69 3.95 0.51 1,028 3.05
Escondida 15,362 0.9 279 0.28 1.35 3.20 832 0.41
Constancia East 16,315 6.0 143 1.97 2.16 0.11 836 0.44
San Jose 6,922 5.8 212 4.49 2.94 0.30 1,078 0.24
Colquipallana 2,944 3.4 220 3.67 5.26 0.21 995 0.09
Total Measured 404,205 5.9 210 2.16 3.43 0.54 1,037 13.49
               
INDICATED
Mine Tonnes Au
(g/t)
Ag
(g/t)
Pb
(%)
Zn
(%)
Cu
(%)
Ag eq gpt Ag eq oz
(M)
Constancia 218,545 6.0 188 2.09 3.08 0.34 968 6.80
Wellington 77,080 6.0 186 1.68 3.66 0.52 1,004 2.49
Escondida 21,406 1.0 238 0.24 1.08 2.84 733 0.50
Constancia East 18,636 5.8 137 1.93 1.95 0.11 798 0.48
San Jose 7,673 5.7 217 4.76 2.93 0.30 1,084 0.27
Colquipallana 5,215 3.4 207 3.31 5.14 0.19 953 0.16
Total Indicated 348,554 5.6 189 1.95 3.05 0.52 955 10.71
               
MEASURED & INDICATED
Mine Tonnes Au
(g/t)
Ag
(g/t)
Pb
(%)
Zn
(%)
Cu
(%)
Ag eq gpt Ag eq oz
(M)
Constancia 488,881 6.1 205 2.24 3.28 0.39 1,021 16.05
Wellington 169,408 6.0 185 1.69 3.82 0.51 1,017 5.54
Escondida 36,767 1.0 255 0.26 1.19 2.99 775 0.92
Constancia East 34,950 5.9 139 1.95 2.05 0.11 816 0.92
San Jose 14,594 5.7 215 4.63 2.93 0.30 1,081 0.51
Colquipallana 8,159 3.4 212 3.44 5.18 0.20 968 0.25
Total M & I 752,759 5.8 200 2.06 3.26 0.53 999 24.20
               
INFERRED
Mine Tonnes Au
(g/t)
Ag
(g/t)
Pb
(%)
Zn
(%)
Cu
(%)
Ag eq gpt Ag eq oz
(M)
Constancia 532,422 5.3 215 1.71 3.29 0.40 950 16.25
Wellington 238,811 5.4 219 1.06 3.95 0.78 1,014 7.78
Escondida 96,926 2.2 208 0.26 2.24 1.90 751 2.34
Constancia East 49,234 5.7 125 1.66 1.57 0.21 760 1.20
San Jose 14,174 5.7 213 4.34 2.78 0.28 1,049 0.48
Colquipallana 11,592 3.7 117 2.98 3.15 0.15 743 0.28
Total Inferred 943,160 5.0 209 1.45 3.25 0.64 934 28.36

Notes for Mineral Resource Estimates:

  1. Cut-offs are based on an estimated $140 Net Smelter Return (NSR)/tonne.
  2. Metal prices used to calculate NSR: $1,300 per ounce (oz) Au, $17/oz Ag, $1.15 per pound (lb) Pb, $1.50/lb Zn, $3.00/lb Cu
  3. Block model grades converted to United States Dollar (US$) value using plant recoveries of 92.1% Ag, 80.2% Au, 77.3% Pb, 82.6% Zn, 52.7% Cu.
  4. Rock Density for Constancia: 3.3 tonnes per cubic meter (t/m³), Wellington, Constancia East, Escondida, San Jose: 3.2 t/m Colquipallana: 2.9 t/m³.
  5. Totals may not agree due to rounding.
  6. Grades in metric units.
  7. All currencies US dollars.
  8. Ag equivalent ounces (eq oz) million (M) is calculated from gpt data
  9.   AgEq g/t = Ag g/t + (Pb grade x ((Pb price per lb/Ag price per oz) x 0.0685714 lbs per Troy Ounce x  10000 g per %)) +(Zn grade x ((Zn price per lb/Ag price per oz) x 0.0685714 lbs per Troy Ounce x 10000 g per %)) + (Cu grade x ((Cu price per lb/Ag price per oz) x 0.0685714 lbs per Troy Ounce x 10000 g per %)) + (Au grade x (Au price per oz/Ag price per oz)).

The above updated resource estimates included in this news release were classified per the CIM Definition Standards on Mineral Resources and Mineral Reserves and, as such, are consistent with the requirements of NI 43-101. The Mineral Resource Estimate was constructed under supervision of Ronald Turner, P.Geo. of Golder Associates S.A., the Qualified Person. The Mineral Resource Estimate was completed using MicroMine 3D geological software, and the inverse distance cubed estimation technique was utilized in the estimation of grade to each of the blocks in the block models.

The Company's QA/QC program includes the regular insertion of blanks, duplicates, and standards into the sample shipments; diligent monitoring of assay results; and necessary remedial actions. Sample assaying was completed at the independent SGS-Lima lab in Lima, Peru. The gold was analyzed by fusion with 30 g fire assay and atomic absorption spectroscopy (AAS) finish, with the resulting values reported in parts per million (code FAA313). The remaining 52 elements were analyzed by mass spectrometry of inductively coupled plasma (ICPMS) and the resulting values were reported in parts per million (code IMC12B). Any gold results that exceeded the limit of detection were re-analyzed by fire assay with a gravimetric finish (code FAG303). Any silver results that exceeded the limit of detection (>10g/t) were re-analyzed by fire assay with a gravimetric finish (code FAG313). Any other metals that exceeded the limit of detection were re-analyzed by ICP-AAS (code AAS11B).