Winter 2011 G&G Lab Notes
This section, from the Winter 2011 issue of Gems & Gemmology, is a compilation of interesting finds from GIA’s laboratories.
The “Type” Classification System of Diamonds and Its Importance in Gemmology
Knowledge of type allows gemmologists to better evaluate if a diamond might be treated or synthetic, and whether it should be sent to a laboratory for testing.
Colour Grading “D-to-Z” Diamonds at the GIA Laboratory
This article discusses the history and ongoing development of GIA's colour grading system, and explains how its laboratory applies it.
A History of Diamond Treatments
Modern gemmologists and diamantaires are faced with a broad spectrum of colour and clarity treatments ranging from the simple to the highly sophisticated.
Latest-Generation CVD-Grown Synthetic Diamonds from Apollo Diamond Inc.
High-quality CVD-grown diamonds, comparable in colour and clarity to natural diamonds, can be identified using a combination of gemmological and spectroscopic properties.
Global Rough Diamond Production Since 1870
Historically, global rough diamond production has fluctuated greatly due to a myriad of causes, many of which are explored in this article.
The Impact of Internal Whitish And Reflective Graining on the Clarity Grading of D-To-Z Colour Diamonds at the GIA Laboratory
This article reviews the GIA Laboratory’s history of reporting on certain types of graining which are often the only characteristics present in large, high-clarity, high-colour diamonds.
The Cullinan Diamond Centennial: A History and Gemmological Analysis Of Cullinans I And II
Eight decades after the Cullinan diamond was mined, a team of gemmologists examined the two famous gems that were created from it to become part of the Crown Jewels of England.
Experimental CVD Synthetic Diamonds from LIMHP-CNRS, France
In the last decade, progress in diamond growth by chemical vapour deposition (CVD) has resulted in significant improvement in the quality of synthetic single crystals.
A Gemmological Study of a Collection of Chameleon Diamonds
Chameleon diamonds are among the rarest of gem diamonds.