Crerarite
Crerarite is an IMA-recognized mineral species in the sulfosalt class, with the chemical formula (Pt,Pb)Bi₃(S,Se)₄₋ₓ (x = 0.4-0-8).
It crystallizes in the cubic crystal system (space group Fm3m). It is a member of the Rocksalt structural group.
Key properties: Mohs hardness 3.5; specific gravity 7.75; Metallic. R: (400) 53.7, (420) 53.8, (440) 53.1, (460) 52.4, (480) 51.6, (500) 50.8, (520) 50.5, (540) 49.9 luster.
IMA symbol Cea, IMA status: approved, named in 1994.
Found in an amphibolite boulder, perhaps glacially transported, containing sulfides.
It is found associated with Chalcopyrite, pentlandite, pyrrhotite, sphalerite, galena, michenerite, actinolite, chlorite, quartz.
The mineral was named to honor Professor David Crerar (1945–1994), economic geologist, Princeton University, Princeton, New Jersey, USA.