A comprehensive, illustrated identification guide for beginners and serious collectors alike, featuring special colour photography of specimens held at the Natural History Museum, London. Rocks are minerals are naturally occurring compounds formed by intense geological processes in the Earth's crust such as volcanic eruptions. With striking colour photography of rocks and minerals from around the globe, this detailed and easy-to-use guide is designed to help readers identify specimens and begin collecting. Fully fact checked by the Department of Mineralogy at the Natural History Museum, London, this guide will give you geological knowledge at your fingertips.