Chrysoprase or chrysophrase is a gemstone variety of chalcedony (a cryptocrystalline form of silica) that contains small quantities of nickel. Its colour is normally apple-green, but varies to deep green.
00000Unlike emerald which owes its green colour to the presence of chromium, the colour of chrysoprase is due to trace amounts of nickel compounds in form of very small inclusions.

Location - Australia, Germany, Poland, Russia, Arizona, California, and Brazil.