Jade comes in two varieties: jadeite, originally found in Guatemala and carved by early Indian civilizations, and nephrite, most famously carved by the Chinese. The largest piece of jade ever found was a 636-ton lens of nephrite jade unearthed in Canada's Yukon Territory in 1992.

Class: semiprecious
Origin of Name: from the Spanish piedra de hijada, name given for the jadeite carved by Indian civilizations of Central America
Color: white to green, orange, brown, lilac (jadeite); green to creamy-white (nephrite)
Chemical Composition: sodium aluminum silicate (jadeite), calcium magnesium aluminum silicate, with some iron (nephrite)
Crystal System: monoclinic (jadeite and nephrite)
Hardness: 7 (jadeite), 6.5 (nephrite)
Specific Gravity: 3.3-3.36 (jadeite), 2.9-3.1 (nephrite)
Geographic Origins: Burma (jadeite); Siberia, New Zealand, Taiwan, British Columbia


Photo: ©International Colored Gemstone Association

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