A large crystal of the rarest mineral polyakovite was discovered in 2019 in the carbonatites pegmatites of pit № 97 of the Ilmeny Mountains. Bodies of carbonatites, glimmerites, glimmerites-pegmatites and carbonatite-pegmatites are located within a small complex body of alkaline ultramafites and carry a unique range of mineral assemblages (rocks), as well as rare-metal and Ree minerals, which is unique for this famous mineral province.

Figures 18. Tables 2. References 12.

Key words: polyakovite-(Ce), rare-metal and Ree minerals, alkaline ultramafites, carbonatites, glimmerite, carbonatite-pegmatites, South Urals, Ilmen Mountains.

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

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

S. V. Kolisnichenko

1. Bazhenov A.G., Nedosekova I.L., Petersen E.U. (1993) [Fluorrichterite Na2Ca(Mg,Fe)5[Si8O22](F,OH)2 – a new mineral species of the amphibole group]. Zapisky VMO [Proceedings of the Russian Mineralogical Society], 122(3), 98–102. (in Russian)
2. Brogger W.C. (1921) Die eruptivgesteinen des Kristianiagebietes, IV. Das Fengebiet in telemarken, Norway.-Norske Vidensk. Selsk. Skrift, 1 math-naturv., (9), 210–222.
3. Kolisnichenko S.V., Popov V.A. (2019) [Polyakovite and other minerals of pit no. 97 in the Ilmeny Mountains]. 12-e Vserossiskie nauchnye chteniya pamyati ilmenskogo mineraloga V.O. Polyakova [Twentieth All-Russian meeting dedicated to memory of Ilmeny mineralogist V.O. Polyakov]. Miass: IMin SU FRC MG UB RAS, 31–38. (in Russian)
4. Melnikov M.P. (1882) [Ilmensky mineral mines]. Gorny zhurnal [Mining Journal], 1(1), 70–151. (in Russian)
5. Nedosekova I.L. (2007) New data on carbonatites of the Ilmensky-Vishnevogorsky alkaline complex (the southern Urals, Russia). Geology of Ore Deposits, 49(2), 129–146.
6. Nikandrov S.N., Popov V.A. (1981) [A new variety of nepheline-hastingsite syenite in the Ilmeny Mountains]. Mineralogicheskie issledovaniya v Ilmenskom zapovednike [Mineralogical studies in the Ilmeny Reserve]. Sverdlovsk: UNTS AN SSSR, 39–44. (in Russian)
7. Polyakov V.O., Nedosekova I.L. (1990) [Mineralogy of fenites and carbonatites after ultramafic rocks of the southern part of the Ilmeny Mountains]. Mineralogiya mestorozhdeniy i zon tekhnogeneza rudnykh regionov Urala [Minerals of deposits and zones of technogenesis of ore regions of the Urals]. Sverdlovsk: UB AS USSR, UrO RAN SSSR, 6–17. (in Russian)
8. Popov V.A. (2007) [Mineralogy of alkaline ultramafic rocks of pite no. 97 of the Ilmeny Mountains]. Mineralogiya Urala-2007 [Mineralogy оf the Urals-2007]. Miass–Yekaterinburg, UB RAS, 256–258. (in Russian)
9. Popov V.A., Pautov L.A., Popova V.I. (2000) [Polyakovite, a new mineral: the results of additional study of chrome-magnesium chevkinite]. Uralskiy mineralogicheskiy sbornik № 10 [Ural Mineralogical Collection no. 10], Miass, IMin UrO RAN, 3–10. (in Russian)
10. Popov V.A., Popova V.I. (2006) Mineralogy of pegmatites of the Ilmeny Mountains. Mineralogicheskiy Almanach [Mineralogical Almanac], Vol. 9. M., Assotsiatsiya ekost, 156 p. (in Russian)
11. Rassomakhin M.A., Kotlyarov V.A. (2018) [Mineralogy of inclusions in corundum from mine no. 418 (Ilmeny Reserve, the southern Urals)]. Mineralogiya [Mineralogy], 4(3), 27–35. (in Russian)
12. Zhdanov V.F., Bazhenova L.F., Polyakov V.O. (1986) [Chromium-magnesium analog of chevkinite]. Novye i maloizuchennye mineraly i mineralnye assotsiatsii Urala [New and poorly studied minerals and mineral assemblages of the Urals]. Sverdlovsk: UNTS AN SSSR, 110–111. (in Russian)