Presents the underlying physics and methodology of this analytical technique, which has become an essential tool in identifying treated and synthetic diamonds.
Read MoreSummarizes data collected by GIA on more than 90,000 natural diamonds in this color range and presents their gemological and spectroscopic properties.
Read MoreSummarizes statistical data and distinctive features of several thousand gem-quality HPHT synthetic diamonds examined by GIA from 2007 through 2016.
Read More
Examines the sources, color, texture, and chemical composition of jadeite from Japanese deposits.
Read More
A report on the color treatment process for these intensely greenish yellow to yellowish green cultured pearls and the techniques for identifying them.
Read More
Documents the retrieval and testing of P. maxima cultured pearls from a Lombok hatchery.
Read More
The geographic source of this rare color-change gem has a significant impact on value. Trace element chemistry profiles allow GIA to accurately determine origin for alexandrite from several countries.
Read More
The relative chemical diversity of emeralds from different deposits worldwide allows clear origin determination in most cases. This contribution explains the criteria used by GIA to make geographic origin conclusions for emeralds.
Read More
Provides a visual guide to the internal features of natural, treated, synthetic, and imitation opal.
Read More
In some cases, the value of a sapphire depends strongly on its geographic origin. This article details the origin data GIA has collected for blue sapphire and describes its methodology for using the data in geographic origin determination.
Read More
