![]() White looks gentle and sophisticated, almost like a gem. Black or Arabic gem is very rare, and therefore it is very expensive. The red type of onyx is considered a kind of standard. The value of stones may vary, depending on their color. White-gray striped pebble, looks rather inconspicuous. This mineral is characterized by a combination of white and brown lines. Combination of white, brown-red and blue stripes. Absolutely white mineral is rare, it is usually pale pink, pale blue or pale aquamarine. So called gems of pink, blue, blue, yellow. Similar to sardonyx, but only red and white lines combined, no brown. ![]() It is completely black or dark gray, has white stripes, translucent. Against the background of a green tone, dark red, brown and white stripes stand out. The main color of the stone ranges from pale green to rich emerald, it arose due to the inclusion of chlorides in the composition. The red color was provided by iron inclusions, the brown color was due to aluminosilicates, and the white color was due to non-ferrous metal oxides. Sometimes white layers are also present in the rock. This mineral combines red or bright orange stripes with brown ones. Many varieties of onyx stone are known by people under completely different names. Russian deposits are located in Chukotka, Kolyma, in Primorye. Good samples are supplied by Australia, Pakistan. There are small deposits, but with very high quality material, in the USA (Colorado, Arizona, California, Virginia, Utah). The most beautiful specimens are now found in Brazil, India, Arabia, Uruguay. Minerals were also mined in India, on the territory of ancient Rome, in Greece. Until now, unique black specimens are found there. The most ancient deposits of onyx were located in the Middle East, the Arabian Peninsula and in Egypt (Nile Valley). In fact, it has nothing to do with the described mineral, but is marble with a striped structure. High resistance to low temperatures (frost resistance)įor decoration of buildings, the so-called Mexican, Algerian or marble onyx is sometimes used.Maximum compressive strength - 50-110 MPa.Hardness on the Mohs scale - 6.5-7 points.The density and composition of the bands depends on the conditions and temperature regime in which the rock was formed.Ĭharacteristics of the main physical and chemical properties of onyx stone: Sometimes in one sample you can find areas with concentric (like agate) and parallel layers. Layers painted in different colors were formed due to the inclusion of impurities - iron, chlorides, magnesium, calcium and other elements. The mineral appeared as a result of sedimentary processes with subsequent crystallization of the rock. These minerals have a similar chemical structure, but the bands of agate are arranged in concentric circles. Onyx is a translucent or transparent stone with a banded structure. It is used as an ornamental stone for the manufacture of dishes, jewelry, expensive cladding. A distinctive feature of the mineral is the presence of parallel colored bands. It was formed by sedimentation of rocks with a high content of quartz.
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