More than 1,500 full-color photos showcase each precious and semiprecious stone in all its singular glory--in both its rough natural state and its polished and cut renditions. Each entry offers complete information on a gemstone's formation and structure, physical properties and characteristics, methods of working, cutting, and polishing. Learn about the best known, including amethyst and diamond. Find full treatments of lesser-known gems, from andalusite to vesuvian. A special section is devoted to rocks as precious stones, including alabaster, onyx, obsidian, and fossils. Organic gem materials are also covered, such as coral, ivory, amber, and pearl, plus new on the market stones like charcoite. Everything is covered, including imitations, synthetics, and combined stones. Charts and tables help you identify unknown gemstones and, when you're in the market, how to check for genuineness. This is truly the ultimate one-volume book every hobbyist, jeweler, jewelry maker and rockhound will ever need!