Pyrrhotite

This sample of pyrrhotite (formed with quartz) is displayed in the Smithsonian Museum of Natural History. Pyrrhotite is a sulfide mineral of iron with the designated composition Fe_1-xS . This sample is about 6x10 cm and is from Trepca mine, Srbija, Yugoslavia.

This sample is about 6x9 cm and is from the same mine. It is also formed with quartz.

This sample of pyrrhotite with sphalerite is about 15x20 cm and is from Santa Eulalia mine in Chihuahua, Mexico. Pyrrhotite is sometimes an ore of iron, but at this mine the ore was the shiny black sphalerite, a source of zinc.