The crystals morphology, mineral assemblages and chemical composition of aeschynite group minerals from the Vishnevye Mountains (South Urals, Russia) are presented. Some veins of syenitic pegmatites host aeschynite-(Ce) and «thoroaeschynite». The calcite-aegirine-feldspar pegmatites and quartz-arfvedsonite veins contain nioboaeschynite-(Ce) and «alumoaeschynite». Aeschynite-(Y) and nioboaeschynite-(Y) are found in annite-feldspar aggregates in assemblage with REE silicates and carbonates. The fnd of nioboaeschynite-(Y) is frst in Russia.

Figures 7. Table 2. References 13.

Key words: aeschynite, alkaline pegmatites, Vishnevye Mountains, SouthUrals.

V.I. Popova, South Urals Federal Research Center of Mineralogy and Geoecology UB RAS, Institute of Mineralogy, Miass, Chelyabinsk oblast, 456317 Russia; popov@mineralogy.ru

V. A. Popov, South Urals Federal Research Center of Mineralogy and Geoecology UB RAS, Institute of Mineralogy, Miass, Chelyabinsk oblast, 456317 Russia

A.V. Kasatkin, Fersman Mineralogical Museum of RAS, Leninskiy pr 18/2, Moscow, 119071 Russia

A.M. Kuznetsov, Oktyabrskaya, 5-337, Chelyabinsk, 454071 Russia

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