Alloclasite

Alloclasite ((Co,Fe)As S) is a sulfosalt mineral. It is a member of the arsenopyrite group. Alloclasite crystallizes in the monoclinic system and typically forms as columnar to radiating acicular prismatic clusters. It is an opaque steel-gray to silver-white, with a metallic luster and a black streak. It is brittle with perfect cleavage, a Mohs hardness of 5 and a specific gravity of 5.91–5.95.[1]

It was first described in 1866 for an occurrence in Romania.[2] Its name is derived from Greek for "other" and "to break," in reference to its distinct cleavage which distinguished it from the similar appearing mineral marcasite.[3][1]

References

http://rruff.geo.arizona.edu/doclib/hom/alloclasite.pdf Handbook of Mineralogy
http://www.mindat.org/min-134.html Mindat data
http://www.webmineral.com/data/Alloclasite.shtml Webmineral data

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.

[Handbook-1] ttp://rruff.geo.arizona.edu/doclib/hom/alloclasite.pdf Handbook of Mineralogy

[2] ttp://www.mindat.org/min-134.html Mindat data

[3] ttp://www.webmineral.com/data/Alloclasite.shtml Webmineral data