Winter Issue of GIA’s Gems & Gemology Highlights Diamonds
Quarterly professional journal reviews auctions, colored diamonds, emeralds and more
The Winter 2014 issue of GIA’s peer-reviewed journal Gems & Gemology (G&G) reviews rough diamond auctions and pricing, the Argyle mine’s pink diamond tenders, a gemological study of the 12.03 carat Blue Moon diamond, the separation of natural and synthetic emeralds using vibrational spectroscopy, and much more. The issue is now available in print, and online with exclusive video content.
G&G’s cover story, “Rough Diamond Auctions: Sweeping Changes in Pricing and Distribution” by GIA Senior Industry Analyst Russell Shor, examines the growing percentage of rough diamonds being sold through auctions, a shift that has caused price volatility while opening up supply to more manufacturers and dealers. He explains that some in the industry advocate auctions as a more accurate reflection of rough diamond market values, while others fear they encourage price volatility and speculation.
Next is “Exceptional Pink to Red Diamonds: A Celebration of the 30th Argyle Diamond Tender,” an insightful review by the GIA laboratory’s John King, Dr. James E. Shigley and Claudia Jannucci. Over the years, GIA has graded extremely rare polished pink diamonds from Australia’s Argyle mine, which have been sold for 30 years through invitation-only tenders. This article presents a concise survey of the color, carat weight and cutting style of the gems offered through those tenders.
In another feature, Dr. Eloïse Gaillou of the Paris School of Mines, Dr. Jeffrey Post of the Smithsonian Institution and their co-authors present a gemological study of the 12.03 carat Blue Moon diamond, an internally flawless Fancy Vivid blue diamond. Discovered at the historic Cullinan mine in early 2014, this diamond set the auction record price for a rough gem prior to its fashioning. In the final article, Dr. Le Thi-Thu Huong from the Hanoi University of Science and her co-authors deliver a preliminary study – contrasting FTIR and Raman spectrometry – on the topic of separating natural and synthetic emeralds using vibrational spectroscopy.
The issue also includes entries on the first non-nacreous beaded cultured pearl, a new Ethiopian black opal deposit, a beryl and topaz doublet set in fine jewelry, and demantoid garnet from a new deposit in Pakistan’s Baluchistan province. Additional details about G&G, full articles, more in-depth coverage, hundreds of additional photos, and exclusive video footage are available on GIA’s website at http://www.gia.edu/gia-news-