PHOSPHATE-RARE METAL CARBONATITES OF THE BELAYA ZIMA MASSIF (EASTERN SAYAN, RUSSIA)

Abstract

The Belaya Zima massif of ultrabasic-alkaline rocks and carbonatites comprises large resources of phosphate-niobium ores, as well as considerable accumulations of tantalum, iron, rare earth elements of the cerium group. Carbonatite exposures in the central area of the massif are overlapped by the weathering crust, a considerable part of which is represented by commercial phosphate-niobium ores comprising pyrochlore, columbite, and other niobium minerals, as well as apatite and francolite, with Nb2O5 content of 1 wt % and P2O5, 15-17 wt %. These ores have been mined at the pilot dressing plant for 15 years. The great extent to which the massif has been studied and the extensive geological prospecting, exploration, and comprehensive research works that have been carried out for 40 years allow us to consider it a standard for assessing other carbonatite massifs, including those poorly studied.