Gemstone Buying Guide
How to Evaluate, Identify, Select & Care For Colored Gems
Tips on Judging Colored Gems
This updated full-color guide to colored gems provides concise yet comprehensive information on quality evaluation, price comparison, gem identification, cutting styles, treatments, fake stones, optical effects, gem care and geographic sources. Many of the gems are shown mounted in striking designer jewelry. There are 323 new color photos and several new gem species and varieties in this new Third Edition. Also included are interesting historical facts mixed with scientific data and a bit of folklore. Written for consumers and professionals, the Gemstone Buying Guide is a practical, well-illustrated resource for buying, identifying and caring for colored gems. If you want to become a savvy buyer and learn how to select colored gemstones, then you’ll find the Gemstone Buying Guide a fascinating and valuable resource.
356 color photos / 156 pages / paperback
$19.95 / ISBN 978-0-929975-51-1 / 7" x 9" (18 x 23 cm)
International Jewelry Publications
Table of Contents
1 Colored Gem Price Factors in a Nutshell 7
Price Factors Explained 7
Two Common Beliefs Which Warrant Review 15
Colored Gem Pricing 16
2 Shape & Cutting Style 17
Gemstone Terms Defined 18
Traditional Cutting Styles 19
Non-traditional Cuts 22
Drusy Gem Materials 28
Trapiche Stones 29
3 Carat Weight 30
Size Versus Carat Weight 30
Effect of Carat Weight on Price 31
Estimating Carat Weight 32
4 Gemstone Color 33
Evaluating Gemstone Color 35
How to Examine Color 35
How Lighting Affects Gem Color 37
5 Judging Clarity & Transparency 38
Gemstone Inclusions 40
Gemstone Blemishes 42
Examining Gemstones for Clarity 42
How Lighting Can Affect Your Perception of Clarity 44
Do We Need Grades to Evaluate Clarity and Transparency? 45
6 Judging Cut Quality 46
Judging the Face-Up View 46
Judging the Profile 48
7 Evaluating Star & Cat’s-Eye Stones 51
8 Treatments & Processes 54
9. Synthetic Stones 58
Synthetic Versus Natural 58
10 Deceptive Practices 60
11 Gemstone Descriptions 63
Amethyst and Other Quartz Stones 66
Chrysoberyl (Alexandrite, Cat’s-eye) 74
Emerald and Other Beryl Stones 76
Lapis Lazuli 94
Moonstone and Some Other Feldspars 96
Ruby & Sapphire (Corundum) 108
Tanzanite and Other Zoisites 114
Andalusite, Apatite 127
Azurite, Benitoite 128
Calcite, Charoite 129
Danburite, Diaspore 130
Diopside, Fluorite 131
Gaspeite, Hematite 132
Kyanite, Larimar 133
Maw-sit-sit, Natural Glass (Obsidian, Moldavite) 134
Phenakite, Prehnite 135
Psilomelane, Rhodochrosite 136
Rhodonite, Seraphinite 137
Serpentine, Sodalite 138
Sphalerite, Sphene (Titanite) 139
Sugilite, Vesuvianite 140
12 Caring for Your Gems 141
Birthstones & Anniversary Stones 144
Gemstones in Order of Descending Mohs Hardness 145
Gemstones in Order of Descending Refractive Index 146
Gemstones in Order of Descending Specific Gravity 147
"Far more than a buying guide, it is one of the finest collections of gem photographs I’ve ever seen. The book is a delight for family and guests when laid on your coffee table...The amount of work in this book is to be believed only by holding it in your hands. If you see the book, you will probably purchase it on the spot."
"An excellent book for the photographs alone, but such a concise way to inform the reader of the many aspects of gemmology and jewellery buying is superb. In an easy-to-read format, Renée Newman has been able to capture the fundamentals of buying coloured gemstones, including jade, opal, topaz, garnet, ruby spinel, chalcedony and tourmaline. The book is illustrated with excellent color photographs, gemstone description charts, and information on evaluating colour and transparency.
The author advises in detail on the majority of gems available to the consumer, including research material on treatments, synthetic stones and styles of cuts. The book discusses prices for each of the gems outlined, as well as quality, evaluation, cleaning and care.
I found this book a pleasure to read and to look at, and have referred back to it many times to verify my own experiences. I recommend this book to all lay people who want to buy gemstones and to gemmologists who need to be reminded of the importance of the buying process–something which we sometimes take for granted."
"Comprehensive, factual and well-presented...Particularly noteworthy in this book are the quality colour photographs that have been carefully chosen to illustrate the text. This is a quality buying guide that is recommended for purchase to consumers, gemologists, and students of gemmology—irrespective of their standard of knowledge of gemmology"
"Certainly successful. It is worth having for both novices and more experiences lapidaries and gem buyers. Novices will be able to learn enough to keep from making costly mistakes, while the more experienced gem buyers and lapidaries can use it for reference...
Newman discusses important topics such as how to judge phenomenal stones, discern deceptive practices and differentiate between various treatments. These aspects are well-covered in the text and are accompanied by excellent color photographs, charts, tables, line drawings and graphs.
Newman’s well-illustrated chapter on shape and cut is particularly useful to students and new buyers of gems since it introduces all the outstanding new cuts that might puzzle cautious buyers.
Readers will learn about color grading, how light affects color, and how color affects the price of gemstones. The chapter on treatments includes filling, impregnation, coating, diffusion and dyeing. Heat treating and irradiation are also discussed along with a list of stones commonly enhanced by irradiation techniques.
The last part of the book has descriptions of gem species and varieties, again with excellent illustrations. Prospective customers learn about hardness, toughness, density, refraction, pleochroism and reaction to heat and chemicals."
"Concise, up-to-date and accompanied by very fine photographs...With colour on almost every opening, few could resist this book whether or not they were in the gemstone and jewelry trade or were gemologists. Here the reader is given all the information needed to show the customer what a stone is, interesting facts about particular species and advice on cleaning and conservation. Some properties have to be given but they are introduced before the stones are described. Since this is not a gem testing book but an introduction to appraising gemstones, we are shown how to evaluate cuts, styles, color, inclusions –all with a view to establishing a specimen within an acceptable order of value as far as is possible. Treatments, phenomenal stones and synthetic stones are also described."
A great book.
Journal of Gemmology
Newman Gem & Jewelry Series and Osteoporosis book links