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FANCY COLOR DIAMOND
Dazzling brilliance. Captivating color. The planet’s most valued gems are fancy color diamonds.
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Research
Fluorescence Produced by Optical Defects in Diamond
How variations in UV lamp output can affect observed fluorescence color and intensity.
Fish-Like Inclusion in Fancy Yellow
A recent lab examination at GIA New York revealed an inclusion in a rectangular Fancy Yellow called "pareidolia," which means it was a resemblance of the scales and form of a fish.
Large HPHT-Treated Fancy Pink Diamond
The New York lab encountered another large HPHT-treated diamond that showed stronger pink coloration.
Green Diamond, Treated with Radioactive Salt
The stone owes all of its green color to these shallow radiation stains.
Strongly Colored Pink CVD Lab-Grown Diamonds
Pink CVD lab-grown products can be separated from natural and treated-color natural pink diamonds by a combination of gemological and spectroscopic properties, which are explored in this study.
Possible “Sister” Stones of the Hope Diamond
A recent study compares a specially created model of the Hope diamond with recent computer models of the French Blue to determine if other stones could have resulted from either recutting.
Summer 2009 G&G Lab Notes
The “Type” Classification System of Diamonds and Its Importance in Gemology
Knowledge of type allows gemologists to better evaluate if a diamond might be treated or synthetic, and whether it should be sent to a laboratory for testing.
Natural-Color Purple Diamonds from Siberia
Twelve natural-color purple diamond crystals from Siberia were studied using spectroscopic methods to better understand their color and its causes.
The French Blue and the Hope: New Data from the Discovery of a Historical Lead Cast
With the use of modern tools and technology, this article sheds light on the history and provenance of both the French Blue and the Hope diamonds.
The Wittelsbach Blue
This article describes what is known about the Wittelsbach Blue since it was first reported in 1666, and the gemological information released to date on this diamond.
Fluorescence Spectra of Colored Diamonds Using a Rapid, Mobile Spectrometer
Numerous natural-color colored diamonds from the Aurora Butterfly of Peace and other collections were studied using a new type of fluorescence spectrometer.
