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A practical guide to gemstone identification

Gem Testing Techniques is the long-awaited work by the internationally-acclaimed gemmologist Alan Hodgkinson FGA DGA, and represents his life-long commitment to, and study of, the gem world. This highly-anticipated book provides an overview of his gemmological knowledge and showcases the gem-testing techniques for which he is world-renowned.

Image of the book - Gem Testing Techniques Image of the book - Gem Testing Techniques Image of a gem testing book Image of a page from a gem testing book

My hopes for my book′s use are two-fold: to aid gem identification, and to encourage an active exploration of gemstones. Regardless of their individual value, each gemstone invariably offers the privileged glimpse of an extraordinary world. In its own individual assemblage of properties and features, we may have the satisfaction of recognition, and surely we would want to share that pleasure with others whether by selling, sharing with friends, or by passing on the information in a teaching capacity.

For the student gemmologist, I sincerely hope Gem Testing Techniques will provide ample signposting and inspiration as it directs you towards the moment of gem identification and the personal satisfaction this brings.

To the qualified gemmologist, I trust you will enjoy the gemmological paths I have travelled, many of which have been trodden previously, as I discovered when reading earlier gemmological literature. The final outcome, ‘Gem Testing Techniques’, you now have in your hands. Enjoy.

Gem Testing Techniques is a case-bound book with 552 full-colour pages richly illustrated with photographs and diagrams. This is a first edition, with a limited print run of 1000 copies. The book has been designed, published and printed in Scotland.

The book chapters are: Magnification, Polariscope/Conoscope, Refractometer, Spectroscope, Specific Gravity, Visual Optics, Acid Testing, Electro-Conductivity, Filters, Hardness, Magnetism, Pleochroism, Radiation, Thermal Testing and Ultraviolet. Appendices and tables: Chrome Spinel, Feldspar, Garnet, Ivory, Physical and Optical Properties (Gems in Alphabetical Order), Optical Properties (Gems in Order of Descending Refractive Index), Glossary of Gem Names and Dispersion Measurement.