The Summer 2006 issue of the Gemological Institute of America's (GIA) award-winning quarterly journal, Gems & Gemology features a report on a powerful new gem characterization technique, a study of the Cullinan I and II diamonds, and more of the latest developments in gemology.
One of the most precise methods for quantitative chemical analysis is laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS). In the lead article, "Applications of [LA-ICP-MS] to Gemology," Ahmadjan Abduriyim and Hiroshi Kitawaki examine this technique's usefulness for detecting the beryllium diffusion of corundum and determining locality of origin for emeralds. Dr. Abduriyim and Mr. Kitawaki, of the Gemological Association of All Japan (GAAJ), conclude that LA-ICP-MS is very well suited for both purposes, with potential use for many others.
"The sophistication of today's treatments and the continual discovery of new gem sources underscore the need for advanced gemological research tools," said Alice S. Keller, editor-in-chief of Gems & Gemology. "This article presents a thorough overview of LA-ICP-MS, how it compares to other analytical techniques, and its current applications in gemology."
The second feature article celebrates the 100th anniversary (in 2005) of the discovery of the largest gem diamond ever found, the 3,106 ct. Cullinan. GIA's Kenneth Scarratt and Russell Shor offer a revealing look at this historic piece of rough and the two famous diamonds that were cut from it with "The Cullinan Diamond Centennial: A History and Gemological Analysis of Cullinans I and II."
Rounding out the Summer issue articles are an investigation into the effects of heat treatment on zircon inclusions in sapphire and the identification information they can provide (by Dr. Wuyi Wang and others), as well as a technique for successfully faceting transparent rhodonite (by Paul Millsteed).The regular Lab Notes section features recent findings from the GIA Laboratory, including three pink diamonds that were identified as coated, an extremely rare inclusion of sapphire in diamond, and three imitation Melo "pearls" that proved to be dyed shell. Highlights from Gem News International include reports on iridescent andradite from Mexico, prehnite from Mali and Australia, and a new red gem material from China called triploidite.
There's also still time to take the G&G Challenge, the annual quiz from the Spring 2006 issue that tests your knowledge of the journal's 2005 articles. Successful participants receive a GIA Continuing Education Certificate and other recognition. The deadline for returning Challenge answer cards is Tuesday, Aug. 1.
To order the new Summer 2006 issue or to subscribe, visit www.gia.edu/gemsandgemology and click on "Ordering and Renewals".
20th August 2006