dioptase

[ dahy-op-teys ]

noun

1. a mineral, hydrous copper silicate, CuSiO 3 ⋅H 2 O, occurring in emerald-green crystals.

dioptase

/ -teɪz; daɪˈɒpteɪs /

noun

1. a green glassy mineral consisting of hydrated copper silicate in hexagonal crystalline form. Formula: Cu 6 Si 6 O 18 .6H 2 O

Word History and Origins

Origin of dioptase¹

1795–1805; < French, equivalent to di- di- ³ + Greek optasía view

Word History and Origins

Origin of dioptase¹

C19: from French, from Greek dia- through + optos visible