- Bournonite, Quartz
- Small Cabinet, 8.4 x 6.7 x 5.0 cm
- Milpo Mine, Atacocha District, Cerro de Pasco, Daniel Alcides Carrion Province, Pasco Department, Peru
Lightly iridescent, splendent metallic-gray bournonite crystals to 1.5 cm are richly scattered amongst milky quartz crystals on this fine and uncommon specimen from the Milpo Mine of Peru. Many of the bournonites have the classic and textbook "cogwheel" crystal form. The 3-dimensional matrix is massive sulfides on this fine specimen, which probably dates to the heyday of specimen production from this district in the 1970s to early 1980s. Bournonite from this locality is very uncommon.