Measured and Indicated mineral resources at Great Panther Silver's (TSE:GPR) (NYSE MKT:GPL) Topia silver-gold-lead-zinc mine in Durango, Mexico, are 41% higher than the same period last year, reflecting continual refinements and improvements in our resource model.
Topia now has 346,200 tonnes of Measured and Indicated ("M&I") mineral resources grading 624g/t silver, 1.31g/t gold, 4.50% lead and 4.19% zinc, containing 11.58 million silver equivalent ounces (ag eq oz).
Inferred mineral resources increased by 29%, year over year, to 357,400 tonnes grading 592g/t silver, 1.31g/t gold, 3.44% lead and 3.96% zinc, containing 11.05 million silver equivalent ounces (see table below for a breakdown).
"The improved modeling, successful in-vein development and better reconciliation between the geological model and actual mine output resulted in an increase in estimated tonnage and contained ounces, in spite of a notable drop in the silver price. In addition, our operations team continues to convert Inferred resources to M&I resources through underground development and sampling, underpinning the long mine life at Topia," said Great Panther's president & CEO, Robert Archer.
The majority of Great Panther's mining to date has come from new mine development on veins reported in these estimates.
Great Panther said that the updated MRE, effective as of November 30, 2014, is consistent with NI 43-101 requirements. It replaces a previous estimate, which the company completed in 2013.
This updated resources accounts for 40 veins from nine mining areas and based on an approximate average Net Smelter Return cut-off value of US$180/tonne, corresponding to 2014 mining, processing, concentrate shipment and treatment, and general and administrative costs for each mining area.
Great Panther has proven its expertise in taking exploration assets through to production in Mexico. In April the silver producer bolstered the Mineral Resource Estimate at its new San Ignacio satellite mine, which forms part of its Guanajuato Mine Complex. It increased indicated resources by more than 30 percent, and more than doubled inferred resources.
Table 1: Mineral Resource Estimate (notes below)
Topia Mine Mineral Resource Estimate, effective date November 30, 2014
Category Tonnage Ag g/t Au g/t Pb % Zn %
Total Measured 180,400 606 1.44 4.26 4.52
Total Indicated 165,800 644 1.17 4.75 3.82
Total Measured & Indicated 346,200 624 1.31 4.50 4.19
Total Inferred 357,400 592 1.31 3.44 3.96
Notes to Table 1
1 CIM Definitions were followed for Mineral Resources.
2 Mineral Resources are reported using different Net Smelter Return (NYSE:NSR) cut-off values for the different mines as follows: US$167/t for the 1522 Mine, US$197/t for Argentina, US$153/t for Durangueno, US$189/t for Hormiguera, US$196/t for Recompensa, US$173/t for El Rosario, and US$204/t for La Prieta.
3 Area-specific bulk densities are 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.
4 A minimum mining width of 0.30 metres was used.
5 Mineral Resources are estimated using metal prices of: US$1,200/oz Au, US$17.00/oz Ag, US$0.90/lb Pb, and US$0.95/lb Zn. Silver equivalent calculations used the same metal pricing and 2014 recoveries of 89.9% for Ag, 56.4% for Au, 94.0% for Pb and 92.3% for Zn.
6 Totals may not agree due to rounding.