Pyrite (Gold bearing)

Cluster of cubic Pyrite crystals from the Carson Hill Gold Mine. The Pyrite crystals are Gold bearing. According to articles on the deposit 'The ore bodies at this mine were formed by extensive hydrothermal alteration and mineralization of fractured metavolcanic and metasedimentary rocks within the shear zones of two principal quartz veins; the Bull vein and Calaveras vein. Unlike typical gold deposits in this area, these quartz veins were unusually low-grade to barren, with the bulk of the gold coming from disseminated sulfides in the altered wall rocks. Locally, greenstone bodies adjacent to the quartz veins contain enough disseminated auriferous pyrite in large enough bodies to constitute what has been called 'gray ore'. Assays of solitary large pyrite crystals averaged greater than 0.333 ounces per ton'. From an old Pyrite collection built in the 1970s-80s.