Aventurine

Aventurine, or AVANTURINE, a vitreous variety of quartz, generally translucent, and of a gray, green, yellow, red, or brown colour, and containing numerous minute spangles. These last are generally mica, but sometimes, according to some authorities, they are scales of metallic copper. It is used in jewelry, but is not so much valued as the finer kinds of amethyst or cairngorm stone. It is found in Silesia, Bohemia, France, Spain, and India, but chiefly in the Ural Mountains, near Ekaterinburg. Beautiful imitations of aventurine are made. The name for the natural substance in fact is borrowed from that applied to the artificial gold-spangled glass which originated accidentally—all aventura (par aventure)—at Murano, near Venice.