dioptase

noun di·op·tase \dīˈäpˌtās, -āz\

Definition of dioptase

plural

-s

  1. :  a mineral CuSiO2(OH)2 consisting of hydrous copper silicate and occurring in emerald-green crystals and massive (hardness 5, specific gravity 3.47)

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Origin and Etymology of dioptase

French, probably from Late Greek dioptos transparent (from Greek dia- + optos visible, from opsesthai to be going to see) + French -ase (as in euclase) — more at optic


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to cast off or become cast off

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