Exploring the Sierra Madre of Mexico for gold and base metals.
San Agustín Vein is located about 1.8 kilometers southeast of the Pueblo of Picachos in the shadow of Cerro San Agustín. Geologically, this vein is controlled by the faulted contact between a Paleocene rhyolitic flow-dome intercalated with coeval pyroclastic rocks to the southeast and metasedimentary graphitic argillite of submarine origin that might be as old as Paleozoic to the northwest. The average vein orientation is 204º/83º WNW, and the true width is five to eight meters. LiDAR data show several shallow pits, trenches and glory holes that define about 275 meters of strike length. Mineral extraction crosscuts 20-, 50- and 220- meters long are present at 680-, 657- and 619- meters elevation.
Mineralization is in quartz veins and veinlets that contain sphalerite, galena, chalcopyrite and electrum. Geochemically, the mineralization is zinc-dominant with lesser lead, copper, silver and gold. Minor amounts of molybdenum and tungsten are present. Alteration minerals are typically illite and smectite clay in the wall-rock and microcrystalline white to grey quartz and calcite in the gangue. Cockade breccias of angular rock fragments surrounded by fine layers of microcrystalline quartz and sulfide are present in some intercepts. This is one of the few veins on the property that does not have mica in the vein selvedges.
holeid | From (m) | To (m) | Width (m) | Au (g/t) | Ag (g/t) | Cu (ppm) | Pb (ppm) | Zn (ppm) | W (ppm) |
---|---|---|---|---|---|---|---|---|---|
HBM-73175 | 0.0 | 1.2 | 1.2 | 184.90 | 61 | 2198 | >10000 | >10000 | 226 |
MCA-65084 | 0.0 | 1.4 | 1.4 | 52.45 | 139 | 1303 | 5511 | 7835 | 173 |
MCA-29887 | 0.0 | 0.6 | 0.6 | 88.20 | 36 | 949 | 9860 | 16550 | 93 |
DH-BRG-001 | 75.0 | 82.0 | 7.0 | 7.45 | 51 | 321 | 1896 | 3373 | 19 |
MCA-65090 | 0.0 | 0.7 | 0.7 | 72.30 | 177 | 889 | 5976 | 13600 | 110 |
MCA-65015 | 3.0 | 5.2 | 2.2 | 20.05 | 103 | 209 | 874 | 879 | 76 |
MCA-65086 | 0.0 | 0.6 | 0.6 | 63.80 | 147 | 2121 | 20200 | 20400 | 116 |
DH-BRG-008 | 84.0 | 92.0 | 8.0 | 3.99 | 21 | 330 | 1203 | 2348 | 6 |
MCA-65087 | 0.0 | 0.6 | 0.6 | 50.10 | 228 | 1360 | 6472 | 25200 | 190 |
MCA-65136 | 0.0 | 2.0 | 2.0 | 14.60 | 45 | 659 | 2609 | 4174 | 24 |
Indicated mineral resources for the San Agustín Vein are 414,188 tonnes of 15.97 g/t gold, 54.8 g/t silver, 0.43% zinc, 0.25% lead and 0.1% copper using a gold-equivalent metal cut-off of 1.83 g/t Au. The estimated metal grade of the indicated MRE closely matches the result of the test mining work completed by Vane Minerals in 2014 of 15.8 g/t Au and 63 g/t Ag across 2.5 m from the south face of Extraction Level 619. In addition, there are an estimated 314,767 tonnes of inferred mineral resources with an average grade of 10.5 g/t gold, 44.4 g/t silver, 0.4% zinc, 0.2% lead and 0.1% copper. Information regarding the mineral resource estimate is here.