A semiprecious gemstone that takes a high polish; is usually green but sometimes whitish; consists of jadeite or nephrite; SYN. jadestone.
Semiprecious stone consisting of either jadeite, NaAlSi2O6 (a pyroxene), or nephrite, Ca2(Mg,Fe)5Si8O22(OH,F)2 (an amphibole), ranging from colorless through shades of green to black according to the iron content. Jade ranks 5.5–6.5 on the Mohs’ scale of hardness.
The early Chinese civilization discovered jade, bringing it from E Turkestan, and carried the art of jade-carving to its peak. The Olmecs, Aztecs, Maya, and the Maori have also used jade for ornaments, ceremony, and utensils.