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 Five years ago this month, the Summer 2002 issue of Gems & Gemology led with a landmark article on pink diamonds. In "Characterization and Grading of Natural-Color Pink Diamonds," John King and colleagues from the GIA Laboratory presented a study of 1,490 natural-color pink diamonds. While the authors observed some overlap in gemological properties between type I and type II pinks, there were distinct differences in their color ranges, ultraviolet fluorescence, absorption spectra, and microscopic features. The article also explained and illustrated the color description terminology used for pink diamonds on GIA grading reports, with a separate section on red diamonds.
Since the publication of this article, several pink diamonds have landed in the public eye. The summer 2003 "Splendor of Diamonds" exhibit at the Smithsonian Institution featured the 59.60 ct Steinmetz Pink diamond. In June 2005, a 3.10 ct Fancy Vivid purplish pink diamond brought $592,129 per carat at auction. Four months later, the 25.02 ct pear-shaped Rose of Dubai fetched more than $6 million. These and other high-profile pink diamonds attest to the growing importance of a gem that was long overlooked.
The pink diamonds report was the third of four major articles on colored diamonds that John King has contributed to Gems & Gemology. The first was "Color Grading of Colored Diamonds in the GIA Gem Trade Laboratory" (Winter 1994), which presented an overview of GIA’s system and terminology for grading colored diamonds. Subsequent articles on type IIb blue (Winter 1998), pink, and yellow (Summer 2005) diamonds provided additional insight on the characteristics and color grading of these gems.
Last year saw the publication of Gems & Gemology in Review: Colored Diamonds, edited by John King. This comprehensive 317 page volume, the second in the G&G in Review series, is a compilation of G&G articles and notes on colored diamonds since the journal’s inception in 1934. It is accompanied by GIA Colored Diamonds Color Reference Charts, a handy reference booklet that shows GIA color grades and descriptions for the most commonly encountered diamond hues, including orangy pink, pink, and purplish pink.
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