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 Next Photo: ©International Colored Gemstone Association The Science Behind the Sparkle | Diamonds in the Sky A Primer of Gemstones | See Inside a Diamond Resources | Transcript | Site Map | Diamond Deception Home Editor's Picks | Previous Sites | Join Us/E-mail | TV/Web Schedule About NOVA | Teachers | Site Map | Shop | Jobs | Search | To print PBS Online | NOVA Online | WGBH © | Updated November 2000