Rare earth minerals in alkaline and Subalkaline rocks of the Balbuk complex (South Urals)
E.P. Makagonov, V.A. Kotlyarov
Mineral composition of alkaline and subalkaline rocks of the Balbuk complex (South Urals) is characterized. The major REE minerals are monazite-(Ce), allanite-(Ce), and rhabdophane-(Ce). The highest REE content with dominant Ce, La, Nd, and Pr oxides is typical of epidote (up to 15.6 wt. %). The REE-bearing epidote crystallized at the last stage of formation of alkaline-subalka-line rocks and at the initial stage of formation of skarns. Rhabdophane-(Ce) is a product of decomposition of REE-bearing epidote during metasomatic processes. The rocks of the Balbuk complex are the primary sources of REEs for amfbole and chlorite rocks, which are developed after alkaline and subalkaline rocks, as well as for weathered rocks.
Figures 5. Tables 7. References 11.
Key words: REE minerals, subalkaline rocks, Balbuk complex, South Urals.
МINERALOGY № 2 2016