Keywords
gemstone
refractive index
density
hardness
purity
cut
inclusions
defect
How to Cite
Abstract
The article discusses the diversity of samples of stones with stars on the surface and the diagnostic characteristics of precious and semipre cious stones with the effect of asterism - an optical effect observed in cabochons or other curved cuts and manifested by the appearance on the surface of the stone during its illumination of a star-shaped light f igure formed by the intersection of several radiant bands at one point and caused by the combined manifestation of refractive phenomena, diffraction and reflection of light from naturally oriented needle-like mineral inclusions (usually rutile) or cavities (growth channels, etc.) in the stone (for example, cat’s eye - an optical effect that appears on the surface of a stone when it is illuminated in the form of a radiant band caused by the oriented reflection of light from inter-parallel thin-fiber mineral inclusions). The purpose of the article is to review gemological, chemical, physical and optical microscopic studies of various types of stones with asterism effect. Since this issue is considered for the first time in the field of forensic institutions of Ukraine and ways to solve it within the framework of forensic homologous examination are proposed, this confirms the relevance of this study.
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