This tetrahedrite is from the Santa Benita Prospect in the Pachipaqui District, Bolognesi Province, Ancash Department of Peru. This district encompasses a large area containing several mines. There are 30 different minerals found in the district including tetrahedrite. It is a sulfide that contains the elements Cu, Sb and S. This specimen consists of a quartz/ sulfide matrix that is covered with tetrahedrite, quartz, galena, and barite crystals. The tetrahedrites are mostly twinned with multiple terminations. The largest crystal is 1/2 inches across and the piece measures 3 1/16 x 2 1/4 x 1 5/8 inches or 78 x 57 x 42 mm.