Famatinite , Pyrite Locality: Pen-Shan Ore Body, Chinkuahshih Mine, Jui-Fang Town, Taipei County , Taiwan Province, Taiwan ( Locality at mindat.org ) Size: 5.3 x 5.0 x 3.7 cm Famatinite is a rare copper-antimony sulfide found in low to moderate temperature copper deposits. This is an exceptional and rich specimen from this uncommon locale of knobby aggregates of sharp, metallic-gray crystals covering the crystallized pyrite matrix. Famatinite is found on both sides of this extremely rich and very rarely available combination example of the species and locale. Ex. Larry Krause specimen — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Famatinite
Famatinite is an IMA-recognized mineral species in the sulfosalt class, with the chemical formula Cu₃SbS₄.
It crystallizes in the tetragonal crystal system (space group I-42m). It is a member of the Sphalerite, Stannite structural group.
Key properties: Mohs hardness 3.5; specific gravity 4.635; Black streak; Dull metallic luster.
IMA symbol Fam, grandfathered status — known before the IMA’s founding, named in 1873.
Found in copper deposits formed at low to medium temperatures.
It is found associated with Pyrite, enargite, tetrahedrite–tennantite, chalcopyrite, covellite, sphalerite, bismuthinite, silver, gold, marcasite, quartz, barite.
The name is derived from the locality, Sierra de Famatina, Argentina.