Gemstones have been a source of delight and fascination for many thousands of years. This revised edition explores the nature of gems, their beauty, rarity and durability, and the mineral properties that govern these qualities. It describes the most popular gemstones in detail and looks at how gem minerals form, where they are found and mined, and how they are identified. It includes information about the popular most popular and the lesser known stones, and describes how to distinguish the real from the fake.