Centuries after it was first discovered, the opal remains the undisputed Queen of Gems. A stone of incredible beauty and variety, with a background rich in myth, adventure, and intrigue, it is considered by many to be the most desirable, the most handsome, and the most precious of all gemstones. The first comprehensive book on the subject in over thirty years, The World of Opals is a complete guide to the science and history of these remarkable gems...