The first
emerald deposits were discovered 90 km NE of the town of Ekaterinburg in the Central Ural Mountains in 1831 - 36. These deposits were named Izumrudnye Kopi and soon became famous worldwide.
The emerald-bearing region is in the Murzinka-Adui anticlinorium, which is a part of the East Urals uplift at the zone of its junction with the Trans Urals depression.
There are 6 major deposits of
emerald and associated
alexandrite in the Izumrudnye Kopi area. In addition, there are approximately 10 minor showings. All emeralds are related to veins of phlogopite glimmerites, which occur within ultramafic lenses and are controlled by a complex system of jointing and schistosity. Thickness of individual glimmerite veins range from 0.2 to 6 m and their length range from 10 to 100 m and more. The veins are grouped into complex veins suites, composed of anastomosing, intersecting, and en echelon veins.
Individual
emerald crystals and their intergrowths occur predominantly in phlogopite and rarely within actinolite, talc, plagioclase, where it is considerably lighter in colour. The crystals of
emerald are prismatic, average size is 1 x 1.5 x 3-5 cm, rarely up to 5 x 20 cm. The colour is saturated bright green, sometimes with a pale and yellow shade. Outer zones of crystals or small individual crystals are transparent. Numerous solid and gas-liquid inclusions are common.
The chromium-bearing
chrysoberyl,
alexandrite, which occurs predominantly in the chlorite zone, also has commercial significance as a gemstone.
The deposits of the Izumrudnye Kopi area differ from each other in the intensity of fracturing and the schistosity of the country rocks, by the size and form of the ultramafic bodies and hosting glimmerites, the degree of metamorphism of the ultramafics, and by specific features of mineral composition.
Ref: E.Ya. Kievlenko, Geology of gems, 2003, p. 80 - 83
Gemstone List
Gem list contains entries from all listed localities in region.
Localities in this Region
Russia | Russia - Sverdlovsk Oblast
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