Dioptase / Quartz

CuSiO,2(OH)2 - Mohs Hardness: 5.  Dioptase is a brightly colored mineral, highly desired for its intense green color. It can form in very distinctive, well-developed crystals, but only a handful of well-known deposits have produced large crystals. Most localities of this mineral, including those in Arizona, only produce microcrystals. Dioptase crystals are generally fragile and can easily break or crumble, and therefore care must be exercised when handling specimens.
Abstract/Description: CuSiO,2(OH)2 - Mohs Hardness: 5. Dioptase is a brightly colored mineral, highly desired for its intense green color. It can form in very distinctive, well-developed crystals, but only a handful of well-known deposits have produced large crystals. Most localities of this mineral, including those in Arizona, only produce microcrystals. Dioptase crystals are generally fragile and can easily break or crumble, and therefore care must be exercised when handling specimens.
Subject(s): environmental sciences