What is "carrollite"

n. (context mineral English) An isometric-hexoctahedral mineral containing cobalt, copper, nickel, and sulfur.

Carrollite, CuCoS, is a sulfide of copper and cobalt, often with substantial substitution of nickel for the metal ions, and a member of the linnaeite group. It is named after the type locality in Carroll County, Maryland, US, at the Patapsco mine, Sykesville.