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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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Fancy Color Diamond Quality Factors
Learn about the factors that make fancy color diamonds so desirable.
Treated “Nickel-Rich” Green Diamond
Examination of a Fancy yellow-green diamond attributes color to both natural and artificial mechanisms.
Treated Orange and Pink CVD Laboratory-Grown Diamond
The Carlsbad laboratory reports on two CVD-grown diamonds subjected to multiple treatments to achieve their final color grades.
Large Orange Rutile Inclusion in a “Chameleon” Diamond
A partially enclosed orange rutile crystal is observed on the crown of a faceted diamond.
Evidence of Focused Beam Irradiation in Treated Pink Diamond
Diamond, Artificially Irradiated and Coated Brown
Examination of a diamond with a rare and highly sought-after Fancy reddish brown color revealed that it had been irradiated and coated.
Treated Pink Type IIa Diamond Colored by Red Luminescence
A type IIa color-treated diamond was graded as Fancy brown-pink under daylight conditions and Fancy purplish gray under incandescent lighting, a color change that resulted from HPHT annealing and irradiation.
Very Large Artificially Irradiated Yellow Diamond
Examination of a 59.88 ct irradiated yellow diamond, one of the largest irradiated diamonds identified by GIA.
Yellow HPHT-Processed Rough Diamond
Mixed-Type Cape Diamond
A Fancy orangy yellow “cape” diamond featured an unexpected 480 nm band, a defect normally associated with orange color.
Abstracts; Fall 1991
This article, from the Fall 1991 issue of Gems & Gemology, is a compilation of abstracts of important gemology-related articles published outside of Gems & Gemology.
A Crystallographic Analysis of the Tavernier Blue Diamond
This study uses both historical information and modern data to create a computer model of the Tavernier Blue, orienting the finished diamond within the original diamond crystal.
