Research Article Search Results

Recently, an unusual 0.94 ct Fancy yellow-brown emerald cut was submitted to GIA for a synthetic diamond grading report. It contained a cloud of black needle-like inclusions occurring along a plane and showed weak green transmission with fiber-optic illumination.

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.

The gemological and spectroscopic characteristics of these type IIa synthetic diamonds suggested that they experienced different growth and/or treatment histories.

This article describes the major gem materials of Vietnam, together with their new finds and recent production.

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

A survey of recent advances in CVD synthetic diamond quality.

A new opal deposit was discovered in 2008 near the village of Wegel Tena, in volcanic rocks of Ethiopia’s Wollo Province.

Advances in technology and increased demand for lower-priced gem materials contributed to the proliferation of new treatments throughout the first decade of the 2000s.

Pink CVD lab-grown products can be separated from natural and treated-color natural pink diamonds by a combination of gemological and spectroscopic properties, which are explored in this study.

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

Since late 2007, rubies and sapphires have been mined by hand methods from both eluvial and primary deposits at Winza in central Tanzania.

The finest and rarest emeralds are sometimes said to have an optical effect called gota de aceite.