Agates Treasures of the Earth Author:Roger Pabian, Brian Jackson, Peter Tandy, John Cromartie The first popular guide to these brilliantly banded and highly prized gemstones. The agate is one of the world's most strikingly beautiful semi-precious gems. Collectors worldwide are drawn to the stone's infinite variety of colorations and banding. Agates form within rock cavities, taking on distinctive shapes and colors according to lo... more »cal geology. While many specimens are readily available, the rare and higher-quality ones are valuable and sought after. This book is a comprehensive, easy-to-use identification guide and worldwide listing of where agates are found. Produced in cooperation with the Natural History Museum of London, Agates is an up-to-date reference and introduction to their formation and individuality. Beautifully illustrated with full-color photographs of superb specimens from around the world, this book is an indispensable resource and reference for amateur gemologists and agate collectors.« less