CAUTION FRAUDERS

Topaz crystals have appeared on the gemstone market, which are processed to get the maximum similarity to diamond crystals. Transparent samples of topaz are given the crystallographic shape of a rhombic dodecahedron, characteristic of diamonds, and also applied to the surface of the facets of the growth line.
Of course, the stone differs in density and other physical properties, however, such samples are often sold to consumers who are not sophisticated in precious stones under the guise of diamonds.
Be carefull!
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В геммологической практике бывают весьма увлекательные случаи с диагностикой ювелирных вставок

Но помимо редкости цвета и высокой стоимости таких камней, многие розовые камни выделяются одной замечательной особенностью – они проявляют плеохроизм, то есть в зависимости от положения осмотра камня он может иметь дополнительные оттенки – оранжевый или пурпурный.

Currently, gemstones are produced by two fundamentally different technological methods - the High Pressure - High Temperature method (“HPHT”, High-pressure & High-temperature) and the Chemical Vapor Deposition (“CVD”, Chemical vapor deposition) method. The "HPHT" method is the most tested classical synthesis method, which can be used both carbon deposition on diamond from flux melts and catalytic reactions. In "CVD" synthesis, diamond growth occurs on a seed during carbon deposition mainly from a gaseous medium at relatively low temperatures and pressures.

Jewelry and precious stones are just such a category of goods, when buying which you need to pay attention to many criteria.

Sogdianite is a rather rare mineral and more often it can be found as a collection material (moreover, in systematic collections), and it is extremely rare in jewelry.