Article Search Results

Show Filters
Showing 40 results for "*"
Article
De Beers Reduces Rough Prices – Too Little?

De Beers reduces rough prices at May sight, undisclosed treated diamonds submitted to GIA and Sotheby’s, Christie’s sales break auction records − again.

Read More

Article
Cut: The 4th C

GIA began issuing reports that included a cut grade for round brilliant diamonds in 2006 in an effort to establish standards for cut in the same manner as it has for color and clarity. This grading system is based on research conducted over the prior decade which was chronicled in several articles published in Gems & Gemology.

Read More

Computer Rendering of the “French Blue” Diamond
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.

Read More

Characterizing Natural-Color Type IIB Blue Diamonds

More than 400 blue diamonds were studied at the GIA Gem Trade Laboratory over several years to reveal additional information about the relationships between their color, clarity, and other gemological properties.

Read More

Whitish Graining with an Amorphous Appearance
The Impact of Internal Whitish And Reflective Graining on the Clarity Grading of D-To-Z Color 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-color diamonds.

Read More

Color Grading “D-to-Z” Diamonds at the GIA Laboratory

This article discusses the history and ongoing development of GIA's color grading system, and explains how its laboratory applies it.

Read More

Faceted CVD Synthetic Diamonds
CVD Synthetic Diamonds from Gemesis Corp

An examination of the gemological and spectroscopic properties of CVD synthetic diamonds from Gemesis Corp.

Read More

Largest CVD Synthetic Diamond Marquise
Very Large CVD-Grown Synthetic Diamond

The New York laboratory recently tested a 2.16 ct CVD synthetic from Scio Diamond Technology Corp., the largest specimen GIA has seen so far.

Read More

A New Method for Detecting Be Diffusion-Treated Sapphires: Laser-Induced Breakdown Spectroscopy (LIBS)

This article describes the first application of laser-induced breakdown spectroscopy (LIBS) to gemology.

Read More

Gemstone Enhancements and Detection in the 1990s

Gemstone enhancements and their disclosure became the most important gemological issue for the jewelry trade in the 1990s.

Read More