Reviews Gems & Gemology, Fall 2015, Vol. 51, No. 3

Books: Exotic Gems, Volume 3

Exotic Gems, Volume 3 Book Cover
By Renee Newman, softcover, 136 pp., publ. by International Jewelry Publications, Los Angeles, 2014, US$19.95.

Renee Newman has created a niche for herself writing guides on different gem materials. Each one has been fact-filled and extremely useful as a buying guide for the general public and gem industry professionals alike. Exotic Gems, Volume 3: How to Identify, Evaluate, Select and Care for Matrix Opal, Fire Agate, Blue Chalcedony, Rubellite Indicolite, Paraíba and Other Tourmalines is the latest book in her Exotic Gems series.

“Exotic gems” are defined by the author and Merriam-Webster’s Dictionary as “gems that are of foreign origin and/or strikingly, excitingly or mysteriously different or unusual.” The gems Newman discusses in this volume are certainly all of the above, and designers are using increasingly unusual materials to fabricate unique pieces of jewelry that reflect the individuality of their clients. 

The book begins with a helpful chapter that describes pricing factors and explains why a particular gem is priced the way it is. With the use of excellent photographs, the value factors for different cuts and saturations are pictured in great depth to help explain the variances in price. Comparisons like this are mentioned throughout the book relative to each gem discussed, each with pictures to reinforce the concept. 

Each gem type is described and discussed in its own chapter. In the case of tourmaline, there is a general chapter on the group, where the major species are listed along with their (complex) chemical formulas. Subsequent chapters are devoted to the various colors of tourmaline, where the proper terminology (e.g., verdelite for green, indicolite for blue) is clarified. A photographic journal of sorts, with captions and tips by master cutter John Bradshaw of Coast-to-Coast Gems, is included so that the importance of the rough’s orientation and the cutting process are properly understood.  Terminology of the different colors of tourmaline (i.e. verdelite for green, indicolite for blue) is discussed and clarified. Following chapters on Paraíba and other copper tourmalines are meticulous descriptions of the history and sources of blue to green tourmalines; pink and red tourmalines; yellow, orange, and brown tourmalines; and multicolored tourmalines (including bi- and parti-color and phenomenal varieties). Tips on evaluation and care are given for each color group. It is truly amazing how much valuable information has been condensed into such an easy format.

The chapter on blue chalcedony contains identification information, accompanied by many photos that exhibit beautiful designs using this unsung gem. Geographic localities follow and include Malawi; Namibia; Indonesia; Mexico; Washington, Montana, California, and Oregon in the United States; and British Columbia in Canada. Assessing the quality of blue chalcedony is discussed, covering hue, tone, saturation, transparency, uniformity of color, clarity, cut quality, and sometimes size and locality. Stability and treatments are listed, followed by a section on care of the material.

Lovers of the elusive fire agate will be pleased to find an informative chapter on this gem. History, deposits, and price factors precede an excellent section on the cutting of this material. Photos and captions by master cutter Ryszard Krukowski of Fire Agate Art Studio explain exactly why so much expertise on the part of the lapidary is required to bring out the magic in the material. Tips on care of the finished product follow.
Matrix opal is the last gem addressed in this guide. Newman explores Queensland boulder, Yowah and Koroit, Andamooka, Mexican, and Honduran opal. The type and amount of material within matrix can dictate enormous differences in price. Generally, Queensland boulder opal commands higher prices than other types of matrix opal so locality can make a difference. The amount or absence of play-of-color, and the type of background the opal is viewed against, can also influence value significantly. Generally, the dark and black body tones are the most prized, because those colors provide a greater contrast to the play-of-color.

One of the most noteworthy aspects of Newman’s many gem-related books is her use of photographs to illustrate quality and showcase modern designs that effectively and beautifully utilize the materials. Details on locality, treatment of material, and care tips are always well researched.

Exotic Gems, Vol. 3 belongs in the library of gem and jewelry appraisers as a quick and easy reference to the relative value factors of the stones discussed, and is also relevant for those who are lovers of unusual gem materials. 

Jo Ellen Cole has worked in the gem industry for more than three decades. Since 2002, she has offered appraisals, identification, and museum display consultation under Cole Appraisal Services.