Gemology

This edition has been revised and expanded to reflect recent and varied developments in the highly specialized field of gemology. Among these are: gemstone synthesis; imitation gems; the alteration of gems to improve, add, remove or otherwise change their color, phenomena or clarity; the importance and widespread uses of the microscope to reflect the aforementioned developments; and a number of new gem minerals or new forms of previously described minerals recently discovered or actively marketed for the first time. The chapter on Descriptive Gemology has been divided into two groups: important gemstones (those gem materials most widely used in jewelry and ornamental objects) and less important gemstones (those less commonly encountered).