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O C T O B E R / N O V E M B E R 2 0 1 7 www.resourceworld.com 59 Drilling operations at the Silver Sand Project near Potosi, Bolivia. Photo courtesy New Pacific Metals Corp. New Pacific Metals finds silver in Bolivian sandstone by Jennifer S. Getsinger, PhD, PGeo Vancouver company New Pacific Metals Corp. [NUAG-TSXV] is most pleased with its Bolivian acquisition of the Silver Sand Project near Potosí, Bolivia according to its new president, Gordon Neal, in a recent interview. The company, with larg- est shareholder Silvercorp Metals Inc. [SVM-TSX, NYSE AMERICAN], also holds properties in China and Canada: the RZY silver–lead–zinc project in the Himalayan plateau and the Tagish Lake (Skukum) gold–silver project in Yukon. Those two projects are undergoing strategic review as New Pacific Metals focuses on advancing its flagship Silver Sand Bolivian project. New Pacific Metals has acquired Bolivian mining company, Alcira, which has several silver-polymetallic mineral properties, most in a very early stage of exploration, except the Silver Sand Project, which is a small historic producer about 25 km from Cerro Rico in Potosí. Alcira carried out a program of drilling there in 2012-2015 using Chinese contractors. Unlike Cerro Rico, which is a Neogene rhyolite dome riddled with sil- ver mining tunnels dating from the 1500s, the Silver Sand property is underlain by Cretaceous sandstone, and has only been mined sporadically since its discovery in the 1500s by Spanish explorers for silver, and in the 1920s for tin. Geological setting is in the Cordillera Oriental of the high Andes, a Paleozoic to Cenozoic fold and thrust belt with young igneous rocks. The Silver Sand Project is located between historic min- ing districts of Cerro Rico de Potosí and Colavi. Northwest-trending belts of folded Ordovician and Silurian flysch (marine) sediments are overlain unconformably by more gently folded Cretaceous sedimen- tary rocks dominated by cross-bedded sandstones which are the host of silver mineralization. Mineralization of the Bolivian tin belt is ascribed to Neogene felsic volcanic and appear to be structurally controlled, run- ning subparallel to as well as crosscutting stratigraphic units and tectonic structures such as folds and faults. At Silver Sand, silver mineralization is hosted in a series of northwest striking silicified fracture zones developed in Cretaceous porous sandstones. Mineralization is characterized by disseminated and stockwork veinlets of sulfides and sulfosalts containing silver, such as acanthite/argentite and proustite – pyrargyrite. What makes the Silver Sand property stand out is the consistently high silver assays, with many samples running more than 100 g/t silver over samples as long as 100 metres in several subvertical tabu- lar bodies up to 125 metres wide and 1.5 km along strike, to a known depth of 400 metres. Although these numbers are from previous owners, they are reported in a recent technical report update. In the spring of 2017, New Pacific Metals drilled four diamond drill holes totaling 1,546 metres to test previous results, and confirmed significant silver mineralization on the Silver Sand property. Examples of drill intersections from each of the four holes (three twin holes and one scissors hole) are as follows: DSS4601, 108.0 m averaging 86.0 g/t Ag; DSS5401, 187.5 m averaging 162.0 g/t Ag; DSS6602, 133.5 m averaging 226.6 g/t Ag; DSS6601, 102.0 m averaging 197.0 g/t Ag. All of the above include shorter inter- vals with higher assays. Initial metallurgy tests by the previous owner also determined an estimated 92% recovery. Conveniently located, the San Bartolomé toll mill near Potosí could be used to process materials from the Silver Sand property. Much more exploration work will have to be done in order to produce a NI 43-101 compliant technical report with verified resource figures. A 30,000-metre drill pro- gram starts in October 2017. The CEO of both New Pacific Metals and Silvercorp, Rui Feng, is known for driving companies to quick production and prof- its, and is estimating a 36-month pathway to production including both open pit and underground mining. President, Gordon Neal, concluded that New Pacific Metals has an "exciting opportunity with Silver Sand's potential to hold both high silver grades and tonnes." n MINING