a usually green or white mineral of the clinopyroxene group, found in igneous and metamorphic rocks. It is used as a gemstone (jade). Composition: sodium aluminium silicate. Formula: NaAlSi2O6. Crystal structure: monoclinic
(jād'īt') A rare, usually green mineral of the pyroxene group. Jadeite can also occur in white, auburn, buff, or violet varieties. The most highly valued form of jade consists of jadeite. Chemical formula: NaAlSi2O6.