Feature Gems & Gemology, Winter 1990, Vol. 26, No. 4

An Investigation of a Suite of Black Diamond Jewelry

This article reports on the gemological properties of six large black diamonds set in a suite of jewelry. The color of the diamonds was determined to be caused by numerous black inclusions lining cleavages and fractures. Such stones are difficult to cut and polish, and require great care in setting. They can be separated from artificially irradiated dark green black-appearing diamonds and from other black and black-appearing materials on the basis of their distinctive visual and gemological features.