Sapphire, like ruby, is a variety of corundum; it gains its color from one or more metallic oxides that appear in the mineral as impurities. The Lone Star, a star sapphire cut in England in 1889, weighs 9,719.5 carats, or about four and a half pounds.

Class: precious
Origin of Name: from the Latin sapphirus (blue)
Color: blue, white, yellow, orange, green, purple, pink
Chemical Composition: aluminum oxide
Crystal System: trigonal
Hardness: 9
Specific Gravity: 3.96-4.05
Geographic Origins: Kashmir (India), Sri Lanka, Burma, Australia, Montana, North Carolina

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Photo: ©International Colored Gemstone Association

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