Naturally Colored Yellow and Orange Gem Diamonds: The Nitrogen Factor
Christopher M. Breeding, Sally Eaton‐Magaña, James E. Shigley
Abstract
mong fancy-color diamonds, those with saturated blue, green, and red colors are the rarest and generally the most highly valued. Over the last decade, however, diamonds with pure hues in these colors have made up less than one-tenth of one percent of all diamonds examined at GIA, making them virtually unattainable in the marketplace. In recent issues of Gems & Gemology, we have documented the gemological and spectroscopic properties of the rarest of fancy-color diamonds ranging from pink-to-red, blue, and green to the more unusual white and black. This article will address the most common colored diamonds, those with yellow hues, while also examining their much rarer orange cousins (figure This is the last of the fancy color groups in this series, and a brief summary of all the colored diamond groups is provided at the end of the article.