About the colors of stones

Historically, in gemology, color varieties have been given incomparably greater importance. At the same time, the collection can be displayed both within the systematic subject matter and within the color series. For example, tremolite can have, in addition to a range of colors from colorless to brownish green, also grassy green for chrome varieties, bright light green for vanadium varieties, pink and purple for manganese varieties. Quartz, fluorite, apatite, tourmaline and beryl are gems that cover the widest possible range of colors and are found in almost all possible color shades. A special direction is occupied by stones with color change effects - alexandite (depending on the type of lighting) and "chameleon" (depending on the temperature of the stone). Among the stones with alexandrite effect, the most common are chrysoberyl (actually alexandrite), garnets, spessartine and pyrope, apatite, and fluorite. It is very rare that the alexandrite effect is found in diamonds. The chameleon effect is most pronounced in some diamonds and manifests itself with a significant (from the point of view of the human body) temperature difference and is expressed in a change in the shade of a yellow or brown stone from distinctly cold (greenish or grayish) to warm (orange or brown).

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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.