pyrargyrite

A deep red to black silver ore with composition Ag₃SbS₃.

An important ore of silver, consisting of the sulphid of silver and antimony.

Ruby silver; dark red silver ore. It is a sulphide of antimony and silver, occurring in rhombohedral crystals or massive, and is of a dark red or black color with a metallic adamantine luster.

Ruby silver; dark red silver ore. It is a sulphide of antimony and silver, Ag3SbS3, occurring in rhombohedral crystals or massive, and is of a dark red or black color with a metallic adamantine luster; it is an important silver ore