This boleite crystal (635) is from the Boleo District in the Mun. de Mulege, Baja California Sur (BC Sur), Mexico. Over 50 mineral species have been identified as coming from this area. It has been mined intermittently since 1885. The extraction of cobalt and zinc minerals made up the primary ores. Boleite is a halide mineral and includes the elements K, Pb, Ag, Cu, O, H, and Cl. This specimen consists of a a pair of twinned boleite crystals they display complex twinning on several surfaces. It measures approximately 8 x 7 x 6 mm.