Identification of HPHT-Treated Yellow to Green Diamonds
Greenish yellow to yellowish green HPHT-treated diamonds exhibited highly saturated body color, well-defined brown to yellow octahedral graining, and visual evidence of heating, among other characteristics.
UV-VIS-NIR Reflectance Spectroscopy of Natural-Color Saltwater Cultured Pearls from Pinctada Margaritifera
Natural-color saltwater cultured pearls from Pinctada margaritifera were studied by diffuse reflectance UV-Vis-NIR spectroscopy
Color Phenomena of Blue Amber
Investigates the presence of fluorescence, rather than iridescence, as the cause of color in blue amber from the Dominican Republic and Indonesia.
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.
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.
Latest-Generation CVD-Grown Synthetic Diamonds from Apollo Diamond Inc.
High-quality CVD-grown diamonds, comparable in color and clarity to natural diamonds, can be identified using a combination of gemological and spectroscopic properties.
Abstracts; Spring 2009
This article, from the Spring 2009 issue of Gems & Gemology, is a compilation of abstracts of important gemology-related articles published outside of Gems & Gemology.
Abstracts; Fall 2009
This article, from the Fall 2009 issue of Gems & Gemology, is a compilation of abstracts of important gemology-related articles published outside of Gems & Gemology.
For the first time, GIA's laboratory has examined tanzanite color-coated with titanium.
CVD Synthetic Diamond with Unusual DiamondView Image
Deep blue fluorescence in a CVD synthetic diamond mimics patterns found in natural specimens.