This sample of tetrahedrite is displayed in the Smithsonian Museum of Natural History. Tetrahedrite is an sulfide mineral of antimony, copper and iron with the composition (Cu,Fe)12Sb4S13 . This sample is about 5x6 cm and is from Park City, Utah.
This sample of tetrahedrite is formed with calcite. It is about 6x6 cm and is from Cavnic, Crisana-Maramures, Romania.