stephanite
Steph"an*ite, n. Etym: [So named after the Archduke Stephan, mining director of Austria.] (Min.) Defn: A sulphide of antimony and silver of an iron-black color and metallic luster; called also black silver, and brittle silver ore.
Steph"an*ite, n. Etym: [So named after the Archduke Stephan, mining director of Austria.] (Min.) Defn: A sulphide of antimony and silver of an iron-black color and metallic luster; called also black silver, and brittle silver ore.