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 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