Gemmological Characterisation of Sapphires from Yogo Gulch, Montana
A look at the mining and distinguishing characteristics of this naturally vibrant blue sapphire.
Black Diamonds from Marange (Zimbabwe): A Result of Natural Irradiation and Graphite Inclusions
Characterises a suite of 40 natural brown to black diamonds from this deposit so that they can be distinguished from suspected treated black diamonds.
Natural-Colour Blue, Grey and Violet Diamonds: Allure of the Deep
Summarises data collected on more than 15,000 natural blue/grey/violet diamonds examined by GIA during the last decade and examines the mechanisms that produce this colour range.
The Very Deep Origin of the World’s Biggest Diamonds
Explores an exceptional family of diamonds, referred to as “CLIPPIR” (Cullinan-like, Large, Inclusion-Poor, Pure, Irregular and Resorbed), that formed in a super-deep environment.
Update on Ammolite Production from Southern Alberta, Canada
There have been a number of changes in Ammolite production from southern Alberta, Canada, since 2001.
Diamonds in Canada
This article chronicles the discovery of primary diamond deposits throughout Canada, whose increasing supply of rough stones will have a growing impact on the world diamond industry.
The Hidden Beauty of Amber: New Light on an Old Subject
The surprising inner world of inorganic inclusions in amber is explored through the use of polarised light and microscopic techniques.
CVD Synthetic Diamonds from Gemesis Corp
An examination of the gemmological and spectroscopic properties of CVD synthetic diamonds from Gemesis Corp.
Abstracts; Summer 2009
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.
Spectral Reflectance and Fluorescence Characteristics of Natural-Colour and Heat-Treated “Golden” South Sea Cultured Pearls
A comparison study was made between the yellow and white nacre of the gold-lipped Pinctada maxima oyster shell and 65 yellow cultured pearls.