/te'treuh hee"druyt/ , n.
a steel-gray or blackish mineral with a brilliant metallic luster, essentially copper and antimony sulfide, (Cu, Fe, Zn, Ag,) 12 Sb 4 S 13 , an end member of a series of solid solutions into which arsenic enters to form tennantite: mined as an ore of copper and silver.
[ 1865-70; TETRAHEDR(ON) + -ITE 1 , modeled on G Tetraedrit ]