Gems : their sources, descriptions and identification.

This updated and expanded edition of the most comprehensive single handbook on gemstones and ornamental stones maintains the effective direction of prior editions (3rd ed., CH, Oct'75) for readers who may range from serious gem collectors to professional gemologists. The original work by Webster (London Chamber of Commerce Gem Testing Laboratory) has been revised by Read, author of the recent Gemmology (CH, Mar'92), and by 15 supporting specialists in the individual chapter topics. The book comprises two divisions: the first includes descriptions of the gemstone minerals, their physical properties, geologic occurrences, geographic localities, and the means of fashioning them into gems; the second provides extensive detail on the methods and techniques of gemstone identification, examination, and laboratory testing. The well-written text is supported by gemstone identification tables, abundant optical property and crystallographic drawings, photographs, photomicrographs, and a few color plates. Well-selected bibliography; thorough index. Recommended for libraries serving gem and mineral hobbyists and for all libraries supporting students in geology and mineralogy. General; undergraduate; professional. W. C. Peters; University of Arizona