Seligmannite Locality: Palomo Mine, Castrovirreyna Province , Huancavelica Department , Peru ( Locality at mindat.org ) Picture width 1 mm. Collection and photograph Christian Rewitzer — Photo: Christian Rewitzer · CC BY-SA 3.0
Seligmannite
A rare lead-copper-arsenic sulfosalt first described from the Lengenbach quarry.
Intro adapted from Wikipedia (CC BY-SA).
Seligmannite is an IMA-recognized mineral species in the sulfosalt class, with the chemical formula CuPbAsS₃.
It crystallizes in the orthorhombic crystal system (space group Pn2_1m). It is a member of the Bournonite structural group.
Key properties: Mohs hardness 2.5–3; specific gravity 5.38; Chocolate-brown to purple-black streak; Metallic. Anisotropism: Strong. R1 –R2: (400) 34.8–36.0, (420) 34.6–35.6, (440) 34.2–35.3, (460) 33.9–35.1 luster.
IMA symbol Seli, grandfathered status — known before the IMA’s founding, named in 1901.
Found in cavities in dolostone (Binntal, Switzerland).
It is found associated with Tennantite, sphalerite, pyrite, dufrénoysite, rathite, baumhauerite (Binntal, Switzerland); tennantite, jordanite, dufrénoysite (Bleikvassli deposit, Norway).
The mineral was named to honor Gustav Seligmann (1849–1920), a mineral collector of Koblenz, Germany.