The results of study of mineralogical-geochemical features of black shales from the frame of the Yayu igneous complex (Polar Urals) are presented on the basis of modern analytical methods in order to identify possible mobilization, redeposition and concentration of ore material during intensive hydrothermal alteration. The high contents of Li, Be, Ba, Ti, Mn, Zr, Rb, Sc, Cs, P, Nb, Ta, Th, and REE are revealed. Rare metal and rare-earth minerals and a silver mineral (most likely, hessite) are found, the presence of alluvial gold in alluvium is established. The metallogenic features of carbonaceous sedimentary rocks afected by hydrothermal processes at the contact zone with igneous rocks are determined. The conclusion is made on a possible fnding of primary gold related to hydrothermal mineralisation in black shale of the region.

Key words: Polar Urals, Yayusky magmatic complex, black shales, rare-earth mineralization.

N. S. Kovalchuk, Institute of Geology, FRC Komi SC UB RAS, ul. Pervomayskaya 54, Syktyvkar, 167982 Russia; kovalchuk@geo.komisc.ru

T. G. Shumilova, Institute of Geology, FRC Komi SC UB RAS, ul. Pervomayskaya 54, Syktyvkar, 167982 Russia;

S.A. Svetov, Institute of geology KarSC UB RAS, ul. Pushkinskaya 11, Petrozavodsk, 185910 Russia

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