The 2017-2018 exploration drilling campaign focused on five targets – Sofía-Julia, Buena Vista, San Pedro Sur, San Pedro Norte (Karina) and Veta Azul. Eighty-three holes, totaling 16,448 meters of core, were drilled as follows:
Sofia – Julia: 8,451 meters in 31 holes.
San Pedro Sur: 3,991 meters in 24 holes.
San Pedro Norte (Karina): 1,007 meters in 14 holes.
Buena Vista: 1,950 meters in 8 holes.
Veta Azul.: 1,049 meters in 6 holes.
The holes are logged and mineralized intervals with enclosing wall rock are sawn in half and sent to the ALS Global Laboratory in Mendoza for preparation and analysis.
For QA/QC, 15% blanks, standards and duplicates are added by Trident. Except for Veta Azul, resources for all drilled veins significantly increased as indicated by plotting grade x thickness of drill intercepts and delimiting areas above the predicted cutoff grade for mining (e.g. economically extractable ore).
Both historic and current drill core and cuttings are stored, with clear markings, in a secured building on site for easy reference. All drill core is boxed at the drill
platform and transported to the logging facility by TRIDENT staff, where the entire core is photographed and logged according to defined project protocols. Visually
mineralized core is sawn in half with half sent to ALS Mendoza for assay. For QA/QC, 15% standards, blanks plus duplicates are added to each assay batch.
Residual Andacollo Mineral Resources were estimated as of November 29, 2016 by Jorge Brantt based on MAGSA data. These resources were classified as Measured, Indicated and Inferred Mineral Resources following the CIM Definition Standards for Mineral Resources and Mineral Reserves guidelines. Resources are reported at a cut-off grade of 1.0 g/t gold equivalent (AuEq) constrained by the actual vein width. The gold equivalence was calculated using a gold price of US$ 1,200 per troy ounce and a silver price of US$ 17.00 per troy ounce as follows:
AuEq =Au (g/t) + Ag (g/t)/70.6
Gold and silver grades were estimated for each block using the inverse distance squared (ID2) method.
