Tao Hsu, Andrew Lucas, and Vincent Pardieu, February 1, 2016
Documents a trip to the renowned opal fields of Lightning Ridge, Koroit, Yowah and Quilpie.
Read MoreRussell Shor, February 1, 2016
G&G Brief presents an overview of the content of the Winter 2015 issue of Gems & Gemology.
Read MoreTao Hsu, Andrew Lucas and Vincent Pardieu, September 16, 2016
Lightning Ridge is the world capital of fine black opals, the most desired of all opals. In June 2015 a group of GIA field gemmologists visited this legendary town in New South Wales, Australia. Come with us to explore this important source of fine opals.
Read MoreTao Hsu, Andrew Lucas and Vincent Pardieu, January 24, 2017
Boulder opal is becoming more and more popular. Australia’s central Queensland is home to more than a dozen of sources of this stone. Come with GIA field gemmologists to find out more about this unique gem.
Read MoreBrendan M. Laurs, Thomas W. Overton
This article, from the Summer 2009 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.
Read More, June 1, 1990
A compilation of gem news from around the world, covering topics such as localities, unusual gem materials, market news, new products, discoveries, jewellery manufacturing techniques and industry trends.
Read MoreNathan Renfro, April 30, 2014
The natural-colour oolitic opal is the largest of its type examined by GIA.
Read MoreRichard W. Wise, March 1, 1993
After almost 75 years of inactivity, the deposits of boulder opal in Queensland, Australia, began to attract new interest in the 1960s and 1970s.
Read MoreJames E. Shigley, Brendan M. Laurs, and Nathan D. Renfro
Commercial quantities of gem-quality chrysoprase and green prase opal (nickel-bearing chalcedony and common opal, respectively) have been recovered from altered serpentinite deposits near Haneti, Tanzania.
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