Emerald, like aquamarine, is a variety of the mineral beryl. The largest gem-quality emerald crystal, found in Colombia's Cruces Mine in 1969, weighed 7,025 carats, or about three pounds.

Class: precious
Origin of Name: from a Persian word that later appeared in the Greek as smaragdos, from which the form esmeralde and later emerald were derived
Color: blue-green to green
Chemical Composition: beryllium aluminum silicate
Crystal System: hexagonal
Hardness: 7.5
Specific Gravity: 2.63-2.91
Geographic Origins: Colombia, Zimbabwe, Zambia, Pakistan, Russia, Australia, North Carolina


Photo: ©International Colored Gemstone Association

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