The host rocks are a part of the Cambrian Lancara Formation limestone.  Two types of mineralization occur at El Valle-Boinás.

1.  Mesothermal magnesian skarn forms a rind around a Permian granitic intrusive.  Known mineralization is higher grade and more continuous along the northern, eastern, and southeastern contacts of the intrusive.  Principal minerals are chalcopyrite, pyrite and electrum.  The mineralized layers are subhorizontal to subvertical.  The Boinás East skarn consists of repeated section due to overthrusting, and
2. Epithermal jasperoid veins and breccias, e.g., A107, Charnela South, hosted by Paleozoic and Tertiary rocks.  High-grade zones are common where these structures intersect skarn mineralization.  Native gold, electrum, and native copper comprise most of the mineralization.

The Company’s recent drill program targeted areas in the A107 vein that would be included in the early years of the conceptual mine plan.  Also, holes were drilled to test the possible connection between the eastern Black Skarn, a.k.a. San Martín, and Boinás East.  Conceptually, it is projected that material from A107 and San Martín will each provide about 235,000 tonnes of feed to the mill for at least 4 years.

EVBC Drill Results

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