Quartz vein gold mineralization in the Klondike Schist: The Mitchell-Sheba system, central Klondike district, Yukon.

The Mitchell-Sheba occurrence is a gold, silver and base metal-bearing quartz vein system contained within a thrust slice of mafic schist that forms part of the Klondike Schist. The vein system formed late in the D4 folding event or subsequently thereafter. Mineralization occurs as gold + silver, base metal sulphides and sulphosalts within quartz veins. Low-grade gold associated with pyrite mineralization is hosted within the surrounding chlorite schist. The mafic rocks are interpreted to be metavolcanic in origin and have reached upper greenschist facies metamorphism. Hydrothermal sericite-carbonate alteration of the host rocks is associated with mineralization and is reflected in the whole rock geochemistry. The prospect underlies one of the larger soil geochemical anomalies in the Klondike region.