Methods and Challenges of Establishing the Geographic Origin of Diamonds

Abstract

GEMS & GEMOLOGY FALL 2022 Some famous diamonds, such as the Hope, the Cullinan, and the 404.2 ct “4 de Fevereiro” diamond in figure 1, have high-profile histories that include their geographic provenance. Other diamonds with a known origin can occasionally be sourced in the marketplace or directly from miners. But for the majority of diamonds, this information is not preserved, instead becoming obscured as they move through the supply chain. To some extent, diamond provenance has not been seen as a valuable piece of information and is not presented as a relevant pricing factor the way it sometimes is for some other gemstones. Rough diamonds are typically bought and sold in lots or parcels based on physical characteristics, including color, clarity, size, and morphology. In assembling these parcels, it is common practice to mix diamonds of similar character from different mines. Faceted diamonds are sold mainly on the basis of the 4Cs (color, cut, clarity, and carat weight) and may be mixed further. Beyond the historical or scientific interest in provenance, several recent developments have put dia mond origin at the forefront of conversations in the industry and among consumers. Initially, this was driven by a need to track conflict diamonds and prevent their entrance into the trade. Now, with mountMETHODS AND CHALLENGES OF ESTABLISHING THE GEOGRAPHIC ORIGIN OF DIAMONDS