Russian Emerald: Gemstone Information
Despite occasional claims that emeralds from the Urals were known and described in classical times the reports cannot be substantiated. It is known that emeralds were discovered in its biotite schist host rock in 1830 or 1831 by a small stream, the Takovaya. Versions of their finding and subsequent history are recounted in Sinkankas
(1981). The best emeralds from the Urals are beautiful and some large crystals have been recorded. The emerald deposits of the Urals were one of the many mineral and gem sites to be investigated by the celebrated geochemist and mineralogist, A.E. Fersman, after whom the A.E. Fersman Mineralogical Museum in Moscow is named.
Fersman wrote papers of particular value for those studying emerald: Izumrudnye kopi na Urale, in Sbornik statei i materialov 46, Materialy dlya izucheniya estesyvennykh proizvoditelnykh sil Ossii, Petrograd [St Petersburg] 1923 [Sinkankas #2044]. Readers should also consult Fersman’s other works. The description of the emerald mines in the Urals by Vlasov and Kutakova has already been mentioned above. The darkest and finest russian emerald crystals occur in biotite schists, others are found in quartz and feldspar. Crystals, often jointed or broken, are long prismatic; frequently a colourless zone surrounds a green core. Quartz and brown mica were reported as inclusions in Ural emerald by Söchting in 1860 (Die Einschlusse von Mineralien, Freiberg, Germany [Sinkankas #6201]). Refractive indices tend to be higher than those shown by other emeralds.
Examination of 100 newly mined and 20 older Uralian emerald, by Schmetzer et al. (Gems and Gemology, Summer 1991), indicated that the characteristic inclusions of Uralian emerald (healed fractures, tubes parallel to the c-axis, flat cavities at right angles to the c-axis, growth banding and biotite-phlogopite mica) are common to emeralds from other sources. Careful examination of emeralds presented from the Urals is therefore needed though confusion with other locations would have little commercial significance. While the Takovaya emerald mines are the best-known in Russia, deposits of beryl are also found in the Chita area of Transbaikalia (south-central Siberia) and in the Ukraine. As far as emerald is concerned, only the deposits in the Ukraine have been reported from altered rocks enclosing a granite pegmatite, at an unpublished location.