Covering 240 commonly-found types of rock, mineral and gemstone throughout the world, Rocks and Minerals is the perfect introduction to this popular subject. Each type of rock or mineral is illustrated with a stunning full-colour photograph. Additional artwork may show the crystalline structure or other identification features. There is a description of each rock or mineral type which includes information on distribution, chemical composition, hardness, colour and texture, and an ID Fact File that offers information at a glance.