Book excerpt: A guide to the major rocks, minerals and gemstones found in Europe. It contains an introduction to the basics of mineralogy, followed by a list of the general features of a rock that can be used in its identification. It also explains how to tell the basic difference between an igneous, metamorphic and sedimentary rock, allowing quick reference to the major identification sections for each of these classes. In these will be found comprehensive descriptions of each rock or mineral, with details of its composition, hardness, specific gravity, colour, fracture, cleavage, streak, lustre, transparency and crystal system, as well as notes on how it is formed and where it might be found, both in the UK and in the rest of the world.