NOTE: Intercepts calculated using a 0.40 g/t AuEq cut-off grade. AuEq (g/t) = gold equivalent (g/t). AuEq (g/t) calculated assuming a long-term gold price of US $1200/oz and a long-term copper price of US $2.75/lb. No adjustment has been made for metallurgical recoveries or net-smelter returns as these remain uncertain at this time. AuEq formula: AuEq g/t = Au g/t + ((Cu% x 22.0462 x 2.75)/(1200/31.1035)) g/t; Ag values are not included. Gold and copper grades capped at 5 g/t Au and 2% Cu, respectively. Intercepts reported as down-hole lengths and may not represent true thicknesses.
Discussion of the Drill-Hole Results
The La Garrucha drill holes are positioned to confirm and expand upon the mineralization encountered in the six holes drilled in 2011-2012 (see news release dated February 29, 2012). Significant intercepts from the previous program include LME-1047 with 64 meters at 0.55 g/t Au and 0.15% Cu, and LME-1040 with 23.89 meters at 0.51 g/t Au and 0.19% Cu. LME-1047 also bottomed in +1.0 g/t gold mineralization. All the holes drilled to date in the west Garrucha area terminate near the La Mina concession limit, without regard to geological breaks or mineralization.
Drill hole LME-1096 (Figure 2) plunges directly eastward from a position roughly halfway between LME-1037 and LME-1047. The La Garrucha mineralized porphyry (mostly G2 Breccia with some G2 Porphyry) reaches its westernmost extent at this location. Levels of gold and copper mineralization are consistent over long intervals, with many of the sub 0.4 g/t AuEQ intervals approaching cutoff. A calculated average over the final 208 meters of LME-1096, ignoring grade cutoff, yields 0.63 g/t AuEq. This is an unparalleled mineralized intercept at La Garrucha, and compares favorably with the long runs of mineralization seen at La Cantera. The final assayed interval contains 2.2 g/t Au, 0.29 % Cu, and 4.8 g/t Ag.
The dominant alteration over much of the G2 Breccia alternates between propylitic and potassic. However, the lower reaches of the drill hole exhibit classic potassic alteration with secondary biotite and potassium feldspar, resembling the alteration seen in the core areas of the La Cantera Deposit. Copper sulfides (chalcopyrite + bornite) are noted over long intervals. The increasing intensity of alteration and mineralization at depth indicates that drilling is approaching the core of the mineral system. Quartz-sulfide veins, some exhibiting open space textures, are interspersed through the mineralized intervals, but predominantly in the shallower portions. These veins usually bring highly anomalous As, Sb, and Ag, along with elevated Au and Cu. These veins are similar to those seen elsewhere in the La Mina district, but the Au and Cu contents are higher at Garrucha than typically seen (see news release dated December 27, 2012).
Drill hole LME-1095 (Figure 3) is collared approximately 100 meters south of LME-1037 and plunges N45E, terminating near the La Mina concession boundary. The edge of the mineralizing G2/G2 Breccia appears to curve back to the east in this area, so this drill hole intersects a shorter mineralized interval. Grades are a slight improvement over the closest 2012 drill intercept (LME-1037 with 30.8 meters of 0.43 g/t Au and 0.06 % Cu, see news release February 29, 2012). Again, the alteration and mineralization increase in intensity towards the bottom of the hole, and this hole also ends in strong mineralization (0.81 g/t AuEq).
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