Black microcrystals of the very rare bismuth telluride mineral pilsenite on a contrasting matrix. From: White Elephant Mine, Vernon, British Columbia, Canada. — Photo: David Hospital · CC BY-SA 4.0
Pilsenite
Pilsenite is an IMA-recognized mineral species in the sulfide class, with the chemical formula Bi₄Te₃.
It crystallizes in the hexagonal crystal system (space group R-3m). It is a member of the Tetradymite structural group.
Key properties: specific gravity 8.4; Metallic. Anisotropism: Noticeable. R1 –R2: (400) 61.6–62.9, (420) 62.3–63.4, (440) 62.8–64.0, (460) 63.2–64.4 luster.
IMA symbol Pse, IMA status: approved, named in 1853.
Hydrothermal in origin.
It is found associated with Hessite, joséite, bismuthinite (Nagybörzsöny, Hungary); tsumoite (Sylvanite, New Mexico, USA); argentian pentlandite, hessite.
The name is taken from the type locality, Nagybörzsöny (Deutsch-Pilsen), Hungary.