'Proustite' definitions:

Definition of 'Proustite'

From: GCIDE

Proustite \Proust"ite\, n. [From the French chemist, J. L. Proust.] (Min.) A sulphide of arsenic and silver of a beautiful cochineal-red color, occurring in rhombohedral crystals, and also massive; ruby silver. [1913 Webster]