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Summer 2004 Gems & Gemology

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Summer 2004 Gems & Gemology Summer 2004 VOLUME 40, NO. 2 EDITORIAL _____________ 103 The Results of Our First Reader Survey Alice S. Keller 105 LETTERS ____________ FEATURE ARTICLES _____________ 106 Gem Treatment Disclosure and U.S. Law Thomas W. Overton A practical guide to the legal requirements for disclosing gem treatments to the buyer. pg. 121 128 Lab-Grown Colored Diamonds from Chatham Created Gems James E. Shigley, Shane F. McClure, Christopher M. Breeding, Andy Hsi-tien Shen, and Samuel M. Muhlmeister Identifying characteristics of yellow, blue, green, and pink synthetic diamonds from a new commercial source in Asia. 146 The 3543 cm-1 Infrared Absorption Band in Natural and Synthetic Amethyst and Its Value in Identification Vladimir S. Balitsky, Denis V. Balitsky, Galina V. Bondarenko, and Olga V. Balitskaya An explanation of the presence or absence of the 3543 cm-1 absorption band, which has been considered indicative of synthetic origin in amethyst. pg. 140 REGULAR FEATURES _____________________ 162 Lab Notes • Notable cat’s-eye alexandrite • Diamond, fracture filled to alter color and enhance clarity • Moon-like surface on a diamond crystal • Cat’s-eye demantoid • High R.I. glass sold as peridot • Dyed jadeite, resembling nephrite • Green quartz with Brazil-law twinning • Synthetic sapphire with unusual yellowish green bodycolor • Spinel with interesting etch tubes • Natural spinel, identified with photoluminescence 170 Gem News International pg. 168 • Amethyst from California • Green petrified wood from Arizona • Unique quartz sculpture from Peru • Scapolite from Mozambique • Update on tourmaline and other minerals from Warner Springs, California • Recent U.S. patents for diamond fingerprinting methods • Colored cubic zirconia Buddha carvings • “Shell pearls” with Tridacna clam shell beads • Fake tanzanite mineral specimens • Conference reports 182 Thank You, Donors 183 Book Reviews 185 Gemological Abstracts pg. 170 The Results of OUR FIRST READER SURVEY his spring, Gems & Gemology conducted a reader sur- We received a number of comments and suggestions with the vey, the first in the journal’s 70-year history. The purpose survey responses, which we intend to explore in the months T was to better understand our readership so we could ahead. These include requests for better explanation of techni- ensure that G&G remains relevant to the needs and interests of cal terms and new analytical equipment, as well as an “Ask its audience. More than 10,600 surveys were mailed to current the Expert” feature and more short notes on current or histori- and former subscribers as well as GIA alumni, and we received cal gemological developments. We will address specific ques- nearly 3,500 replies, including 42% of our current subscribers tions about G&G editorial practices in future Letters sections, from all over the world (a truly amazing response rate). so we can share the information with all readers. Before sharing the results, though, I’d like to thank all the respon- Among the comments were several compliments, which we dents for taking time to provide us with valuable feedback. We hope match your experience as well: needed to hear from you, and you delivered for us. I also want to Having your publication in my home and waiting room is congratulate to Jonathan Ng (San Gabriel, California) and tremendous to my business. It’s educational and informa- Colleen Ann Murtha-Stoff (Tucson, Arizona), whose survey cards tive even to the general public, which is also a reflection were randomly drawn to win three-year subscriptions to G&G, on me. and lifetime subscriber Roland Schluessel (San Francisco), who chose the $200 Gem Instruments gift certificate. I cannot begin to enumerate the useful and critical infor- mation Gems & Gemology has brought to me, but I am Who Reads G&G? grateful and I do hope that you keep up the good work. Fifty-nine percent of the G&G subscribers who responded are Gems & Gemology is the most brilliantly conceived, best male, while 39% are female (2% did not reply to this question). organized, and most beautifully executed magazine I The mean age is just under 52 years old. Nearly 60% have sub- have ever read. How do you consistently continue to scribed for more than five years. Seventy percent are employed produce so superbly? [Answer: A great staff and terrific in the gem and jewelry industry, most for 10 years or more. The contributors and reviewers.] G&G reader is affluent, with a mean annual income of $90,270. (We’d like to think that reading the journal has helped them Looking Ahead reach—and maintain—this financial success.) Now that we’ve compiled the results, we want to use the infor- Although the top occupation is retail mation constructively. It is evident that our readers like what is jeweler, claimed by 38% of the being presented in G&G, and we appear to be meeting their respondents, our readers also include needs. Yet it is critical to the future of gemology that we attract appraisers, jewelry designers, whole- more younger, less-affluent readers. We need to encourage salers, and lapidaries, as well as edu- them to continually upgrade their knowledge of gemology— cators, research scientists, and labo- and we need to help them by keeping the cost as affordable as ratory gemologists. We were pleased possible. We also want to see even more retailers embrace the to see that, in many cases, each copy information in G&G. As our managing editor Tom Overton delivered is read by several people. points out in his lead article this issue, there are stringent legal requirements for disclosure in the United States. The retailer Colored stones are the primary area of interest for 45% of the must first know his or her product and then be able to commu- subscribers, followed by diamonds at 28%. Identification nicate that information to the customer. We do not see the techniques, synthetics/simulants, and treatments round out the need to make any radical changes (a concern expressed by one top five interest categories. long-time subscriber), but we will take these and the other Taking Stock results and recommendations into consideration as the journal Satisfaction is high, with 87% of current readers being “Very continues to evolve. Satisfied” with G&G. When combined with “Mostly Satisfied,” Of course, any time you have a suggestion or an opinion you’d the total is 99%. Sixty-eight percent of the respondents identi- like to share with us, there’s no need to wait until our next fied G&G’s articles as their primary feature of interest, followed G&G reader survey—just e-mail us at [email protected]. Gems & by the Lab Notes and Gem News International sections. Gemology is your journal, and we want to know what works— Of those 13% who were not “Very Satisfied,” the chief concern and what doesn’t—for you. was that the journal was too technical. However, this represent- ed less than 4% of our subscriber respondents and was men- tioned by less than 2% of the former subscribers as the reason they no longer subscribed (cost was the primary concern for this younger, less-affluent group, followed by the fact that they had left the profession). Alice S. Keller Editor-in-Chief EDITORIAL GEMS & GEMOLOGY SUMMER 2004 103 LETTERSLETTERS An Old Technique to Solve a New Problem? After development, the photographic plate was insert- In the conclusion of the recent G&G article on beryllium- ed in a photographic microphotometer, so that the peak diffused ruby and sapphire (J. L. Emmett et al., Summer height of the strongest emission spectrum line of the test 2003, pp. 84–131), the authors state that “Today, there is no element could be measured. In the case of beryllium, a simple, low-cost alternative to SIMS or LA-ICP-MS, but we suitable neighboring aluminum spectral line peak would are working on the problem and strongly encourage others to also be recorded. As the Al concentrations of all rubies and do so as well.” This writer believes that there does exist a sapphires are virtually constant, the ratios of peak heights, h / h , would be independent of exposure times. Thus a low-cost plasma-based method that might reach the sensi- Be Al plot of h / h versus Be concentration in ppma would tivity required for detecting Be-diffused corundum, that is, Be Al about 5 ppma. It is a long-forgotten technique, whose instru- yield a working analytical linear graph. Variations in arc mentation seems to have been abandoned by those compa- emission power during the entire specimen vaporization nies who specialize in spectroscopy-based analytical devices. period would in no way affect the accuracy of the test This technique employs a carbon arc emission spectro- analysis. The great virtue of photographically recording scopic unit. Known as the Hilger Medium Quartz the period of the entire specimen vaporization is that all Spectrograph (HMQS), it was designed and manufactured the Be-emitting photons would be integrated, along with by Adam Hilger Ltd., London, who abandoned its produc- those of the calibrating aluminum-emitting photons. tion in 1961. It was a remarkably successful analytical tool The sample for analysis had to be obtained by mechan- for the measurement of certain major, minor, and trace ical means, but this can be done in a manner that is not chemical elements. The plasma-excitation method used likely to affect the gemstone's optical appearance. The was a high-voltage AC condensed-spark emission from writer’s experience with optical sampling of only the cath- opposed specimen rods, unlike the DC carbon arc emission ode layer zone of the DC carbon arc plasma indicated that spectrographic method proposed here.
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