Practice of Diamond Examination in Modern Conditions: Classification and Main Types of Diamonds

The article addresses topical issues of instrumental diagnostics of diamonds’ origin in the context of the modern jewelry market characterized by the widespread appearance of synthetic and treated stones. The objective of the study is to define the key diagnostic optical features necessary for the reliable identification of diamonds’ nature of origin.

The paper summarizes findings of The Russian Federal Centre of Forensic Science expert practice findings of examination of 55 samples using a complex of non-destructive methods (including visual analysis, optical microscopy, FTIR spectroscopy, and photoluminescence spectroscopy).

The study considers and provides the detailed characteristics and spectral markers for four primary types of cut diamonds: natural diamonds (Type IaAB), natural diamonds treated with high-temperature HPHT-annealing, and synthetic HPHT and CVD diamonds.

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