Gem Testing

This unusual work is a complete treatise on the identification of precious stones that is thoroughly recommended for inclusion on the jeweller or antiquarian's bookshelf. Contents Include: Preface; How to Use The Book; Refractive Index and its Measurement; Double Refraction and How to Detect it; Colour, Colour Filters and the Dichroscope; Specific Gravity and How to Measure It; Detection of Synthetic and Imitation Stones; The Use of the Microscope; The Identification of Diamond; The Identification of Ruby; The Identification of Sapphire; The Identification of Emerald; Aquamarine and Alexandrite; The Identification of Zircon; The Identification of Topaz; The Identification of Pink, Mauve, etc. Stones; The Identification of Brown and Orange Stones; Quartz, Opal, and Garnets; Tourmaline, Peridot, and Spinel; Identification of Translucent and Opaque Stones; Amber, Tortoiseshell, Coral, and Jet; Pearls: Real, Cultured, and Imitation; Appendix: Glossary, Alphabetical Summary of Gem Species, Crystal Systems, Bibliography, Specific Gravity and Refractive Index Tables; Names and Addresses of Recommended Suppliers; and an Index. Many of the earliest books, particularly those dating back to the 1900s and before, are now extremely scarce and increasingly expensive. We are republishing these classic works in affordable, high quality, modern editions, using the original text and artwork.