Dioptase Reference Libraries
Dioptase is an intense emerald-green to bluish-green copper cyclosilicate mineral. It is transparent to translucent. Its luster is vitreous to sub-adamantine. Its formula is CuSiO3Â·H2O (also reported as: CuSiO2(OH)2). It has a hardness of 5, the same as tooth enamel. It specific gravity is 3.28 - 3.35, and it has two perfect and one very good cleavage directions. Additionally, dioptase is...
- A large punch-bowl of the eighteenth century, usually of silver and with a movable rim, and decorated with flutings and a scalloped edge. It was also used for cooling and carrying wine-glasses.
- A kind of cotton handkerchief having white spots on a colored ground, the spots being produced by a chemical which discharges the color.