For centuries, all yellow stones were thought to be topaz, and all topaz yellow. Today, the many colors of topaz are well-known. Since 1988, the Smithsonian Institution has displayed the 22,892.5-carat (or roughly 10-pound) American Golden Topaz.

Class: sometimes considered precious
Origin of Name: reputedly named after Topazius, the ancient Greek name for the Red Sea island of Zebirget (though only the gem peridot is found there); alternatively, may derive from the Sanskrit tapas (fire)
Color: clear to pale blue to yellow, orange, brown, and pink
Chemical Composition: aluminum fluorosilicate with some hydroxyl
Crystal System: orthorhombic
Hardness: 8
Specific Gravity: 3.49-3.57
Geographic Origins: Brazil, Russia, Mexico, California, Colorado, Utah, Maine, New Hampshire

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Photo: ©International Colored Gemstone Association

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