Since ''Gemmology'' was published, readers have used it to gain an in-depth appreciation of the science of gemmology, its history and practice.This third edition has been completely revised to cover the latest methods of gem enhancement and identification, as well as the latest test instruments and laboratory techniques.''Gemmology'' serves as an invaluable reference guide for gemmologists, professionals and students, and is an invaluable text for anyone in the gemmological profession. Also included are details of the Gemmological Association's Foundation Course together with advice on examination techniques.