tetrahedrite

noun

tet·​ra·​he·​drite

plural -s

: a fine-grained gray mineral (Cu,Fe)₁₂Sb₄S₁₃ that is isomorphous with tennantite, consists of a sulfide of copper, iron, and antimony and often also contains zinc, lead, mercury, or silver, occurs in characteristic tetrahedral crystals and also in massive form, and is often a valuable ore of silver and is also worked for copper (hardness 3–4, specific gravity 4.4–5.1)

Word History

Etymology

German tetraëdrit, from Late Greek tetraedros having four faces + German -it -ite

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