Exotic Gems, Volume 3
How to Identify, Evaluate, Select and Care For Matrix Opal, Fire Agate , Blue Chalcedony, Rubellite, Indicolite, Paraiba and Other Tourmalines
Exotic Gems, Volume 3 is the third in a series of books that explains with close-up photos the price factors and identifying traits of unusual gems. The stones are shown not only loose but also in jewelry, in the rough and as beads. Fun facts, historical anecdotes, geographic sources, gem treatment information, cutting advice, and tips on gem care are included along with diagrams and tables to aid in identification and evaluation. If you’re interested in matrix opal, fire agate, blue chalcedony, Paraiba tourmaline, rubellite or other tourmalines, Exotic Gems can provide you with jewelry design ideas and in-depth information that will help you be a smart buyer and seller. Written in a succinct and user-friendly style, Exotic Gems: Volume 3 is an ideal reference for jewelers, sales associates, appraisers, gem collectors, gemology students, designers gem dealers and consumers.
by Renée Newman
Paperback / 6" x 9" / 136 pages / 422 color photos /
International Jewelry Publications / $19.95
The simple genius in Renee Newman’s Exotic Gems series is that no books like them have been written. Of course there are several places to find buying guides; a simple search for “gemstone buying guide” will yield many results. What these other guides cover however can be found within the first twenty pages of Exotic Gems. What follows in Volume Three, as with its predecessors, is a wholly comprehensive look at specific varieties of gems not commonly featured in jewelry store cases.
Covered in Volume Three are four selections, including Matrix Opal, Fire Agate, Blue Chalcedony, and several varieties of tourmaline. For each of these gems is an entire section of Exotic gems designed to provide the reader with everything they need to know, whether caring for a gem they already have or seeking to purchase one. The stones are described in great detail, including origin, localities, varieties, care information, and possible treatments.
The most represented stone in Exotic Gems Volume 3 is Tourmaline, and represented it surely is. Over sixty pages, Renee Newman describes the history of Tourmaline, it's chemical and optical properties, and each of the many unique varieties of tourmaline in depth. As you read through the book, there are also several very informative sections that many people aren't familiar with, including a section on the steps to cutting fire agate, and one on treated Andamooka matrix opal.
Maybe the most impressive feature of Exotic Gems is its amazing wealth of photographs. Over 100 individuals and companies in the gemstone trade have donated their images to this volume alone, and the end result is a book that provides as much information visually as it does through Renee's excellent writing.
Jeweler's Ethics Association
This is the latest volume in Renée Newman’s library of delightfully illustrated and useful books. This edition focuses on some of the less commonly seen stones, including matrix opal, fire agate and the various members of the tourmaline family, which, although not the rarest gemstones, are deserving of more recognition than they currently get.
Renée begins by looking at the factors that affect the value of these stones, and goes on to systematically investigate the properties of each stone, showing why they deserve the label of ‘exotic gems’.
One interesting inclusion in the volume is that of pink tourmaline. Although probably not considered exotic by many, pink tourmaline quite rightly deserves a place because of its historical importance, being highly sought after by the Chinese Empress Dowager Tzu-hsi, who was laid to rest with a pillow carved from this much-beloved material. Stories such as this, interspersed throughout the book, bring the human element of gemstones and gemmology into what other texts might treat as a simple discussion of properties and effects.
Nonetheless, the various optical effects of each stone are still covered and, in this respect, tourmaline is probably the most amazing stone. Standard uni-colour tourmalines are mentioned, followed by a discussion on the many varied colour effects that tourmaline is capable of showing. Renée notes that striping across the crystal is common, with many colours seen in various combinations, but also discussed is the concentric banded form (watermelon), along with the rarer chatoyant, colour-change and Usambara effect forms.
Fire agate also features, with details on which of its iridescent colours are the most desirable and/or valuable, and the known sources worldwide. As with the section on tourmalines, detailed images of professional cutters are included, along with commentary from master cutters specializing in each material.
Matrix opal and blue chalcedony are the remaining two stones covered, and each is considered with the same level of care and attention to detail. When discussing blue chalcedony, Renée focuses on the different localities that this material can be sourced from — an important feature for collectors.
The range and variety of colours and structures that this material takes are also covered, with various cutting styles designed to enhance these features.
Matrix opal, which is often overlooked in textbooks in favour of the more ‘desired’ forms of precious opal, gets a well-deserved review, and the images included here show that this has a unique appeal all of its own. Different formations and localities are dealt with and even a form of synthetic matrix opal is included.
Overall, this is another excellent addition to the famous and much-loved Renée Newman series. The information contained is wide-ranging, ensuring that there is something for everyone, whether amateur collector or serious gemmologist.
Andrew S. Fellows FGA DGA, Gems & Jewellery, published by the British Gemmological Assn.(Gem A)
. . . The book [Exotic Gems, Volume 3] is intended to be an ideal reference for consumers, jewelers, sales associates, gem dealers and collectors, gemology students, as well as appraisers. Newman continues to amaze the reader with a wealth of information regarding the lesser known colored gemstones. The author delves deep into the history, origin, geographic sources and any available or common gemstone treatments. Tables are included to aid the reader with the unique gemstone’s characteristics, such as refractive index reading, specific gravity, spectrum, reaction to UV fluorescence and magnification, stability to light, etc.
Volume 3 explodes with numerous detailed, colored photographs of the exotic gems, both loose and mounted. The photos help the reader in understanding identification traits and certain value factors. Also of interest, are step-by-step photos with captions of How a Master Cutter Cuts a Tourmaline as well as Fire Agate.
Exotic Gems is extremely well organized and quite easy and interesting to read. I look forward to adding all of the other volumes to my library collection; especially for the fun facts, historical anecdotes and exquisite photographs.
As a jewelry appraiser and gemologist, I feel that this information in particular will serve as a great reference; especially when we have very inquisitive clients asking, for example, why we don’t automatically label a blue-green tourmaline a “Paraiba.” The quality of the photographs and their individual reference information listed can also be a great asset to an appraiser; helping locate possible comparison gemstones, designers, and/or gemstone dealers.
Renée Newman’s Exotic Gems series is full of important information that would be a great tool for any and all consumers who have an interest in purchasing these different, unusual and fascinating colored gemstones. At the low retail price of $19.95, how can we possibly pass them up?
Reviewed by Katy Bodenburg, GG, NAJA Appraiser
The rather lengthy subtitle of this superbly written book is “How to Identify, Evaluate, Select and Care for Matrix Opal, Fire Agate, Blue Chalcedony, Rubellite, Indicolite, Paraiba and Other Tourmalines. Geared toward the lapidary and jewelry artist rather than the specimen collector, the book offers a detailed chapter on the many factors involved in pricing gems, including color, clarity, transparency and brilliance.
Throughout the 136 pages, the major emphasis is on the popular varieties of tourmaline, which fill seven chapters. The varieties are grouped according to color and source. The section on cutting tourmalines is particularly useful.
The skillful use of nearly 400 color images to highlight various gems and their characteristics makes this a delightful book to peruse. For jewelry designers, many photographs—several by my friend Frank Heiser— illustrate a great variety of creative designs.
The earlier volumes in the Exotic Gems series deal with tanzanite, ammolite rhodochrosite, zulatanite, sunstone moonstone and other feldspars (Vol 1) and alexandrite andalusite, chrsoberyl cat’seye, kyanite, common opal, fire opal, dinosaur gemstone, tsavorite, rhodolite and other garnets (Vol 2).
These books are must haves for the libraries of jewelry designers, gemstone cutters, and anyone who simply appreciates colorful gemstones.
Bob Jones, Rock & Gem
Table of Contents
1. Exotic Gems 9
2. Price Factors in a Nutshell 12
Price Factors Explained 12
Cutting Style 18
Cut Quality 18
Carat Weight or Stone Size 20
Treatment Status 20
Copper, Chromium and/or Vanadium Content 20
Geographic Origin 20
Distinctness of Optical Effects (Phenomena) 21
Colored Gem Pricing 22
3. Tourmaline Group 23
A Brief History of Tourmaline 23
What is Tourmaline? 2
Identifying Tourmaline 28
Tourmaline Chemistry 29
Tourmaline Species Characteristics in Brief 31
Tourmaline Varieties 33
How a Master Cutter Cuts a Tourmaline 34
Cutting Tourmaline (by John Bradshaw) 38
Caring for Tourmaline 38
4. Paraiba & Other Copper Tourmalines 39
What is a Paraiba Tourmaline? 42
Identification of Cuprian Tourmaline 45
Price Factors for Copper-Bearing Tourmaline 47
Alternative Terms for “Paraiba” 48
5. Blue to Green Tourmalines 49
What is Indicolite? 49
What is Chrome Tourmaline? 50
Verdelite or Green Tourmaline? 52
Blue-green Tourmaline 55
Gray Tourmaline 56
Identifying Green Tourmaline 57
6. Pink & Red Tourmaline 58
What is Rubellite? 60
Evaluating Pink & Red Tourmaline 63
Sources of Pink & Red Tourmaline 64
7. Yellow, Orange & Brown Tourmalines 66
8. Multicolored Tourmalines 70
Formation of Multicolored Tourmaline 72
Effect of Color Zoning on Pricing 74
Pleochroic Multicolor Effect 74
Multicolored Tourmaline Jewelry 75
9. Cat’s-eye & Color-change Tourmaline 79
Color-change Tourmaline 81
10. Blue Chalcedony 86
What is Chalcedony? 88
Identifying Blue Chalcedony 90
Geographic Sources of Blue Chalcedony 91
Judging Blue Chalcedony Quality 97
Caring for Blue Chalcedony 98
11. Fire Agate 99
Fire Agate Price Factors 101
Cutting Fire Agate 104
Caring for Fire Agate 108
12. Matrix Opal 109
Boulder Matrix Opal 112
Andamooka Matrix Opal 120
Honduras Matrix Opal 122
Mexican Matrix Opal 124
Identifying Traits of Opal 125
Pricing and Evaluation of Matrix Opal 127
Caring for Matrix Opal 130
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