Illustrated Encyclopedia of Rocks, Minerals & Gemstones

This is the ultimate photographic guide to the world of rocks and minerals, and how to build your own collection. A comprehensive introduction explains the formation and clification of the many types of rock, mineral, and gemstones, with clear photographs of some of the world's most bizarre and beautiful examples. Expertly written text describes the impact of factors such as time, weather and water erosion on the development of rocks and minerals in the landscape, and the part played by natural phenomena such as volcanoes and earthquakes. It clarifies how contact with heat and pressure can affect external characteristics, and prompt the metamorphosis of one rock into another. There is advice for the amateur geologist on using equipment, field work, maps, tools and home testing techniques, to identify and source geological specimens. A comprehensive photographic directory illustrates over 300 examples of minerals and rocks from all over the world. Specimens are grouped according to their chemical composition and characteristics, and all entries include quick-reference identification checklists to aid recognition. Featuring over 800 photographs and artworks, this is a visual encyclopedia and field guide on a richly consuming and endlessly fascination subject.