Grey black metallic crystal aggregtaes of the rare sulphide mineral hammarite from New Mexico (Victorio District, Luna County, New Mexico, United States of America). Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Hammarite
Hammarite is an IMA-recognized mineral species in the sulfosalt class, with the chemical formula Cu₂Pb₂Bi₄S₉.
It crystallizes in the orthorhombic crystal system (space group Pbnm). It is a member of the Meneghinite structural group.
Key properties: Mohs hardness 3–4; specific gravity 6.74; Black streak; Metallic. R1 –R2: (400) 39.7–43.6, (420) 39.8–43.7, (440) 39.8–43.8, (460) 39.9–44.0, (480) 40.1–44.1, (500) 40.3–44.4 luster.
IMA symbol Hmr, grandfathered status — known before the IMA’s founding, named in 1924.
Hydrothermal in origin.
It is found associated with Paděraite, pekoite, bismuthinite, chalcopyrite, grossular, andradite (Băiţa, Romania); pyrite, sphalerite (Dzhida deposit, Russia).
The name is derived from the locality at Gladhammar, Sweden.