RARE-METAL GRANITES AND ORES OF THE TIGRINOE DEPOSIT, CENTRAL SIKHOTE-ALIN

New data are presented on the age, composition, and origin of rase-met al granites and associated tin-tungsten mineralization of the Central Sikhote Alin, Primorskii Krai, at the Tigrinoe deposit. The granites w ere formed during two successive subphases: the first subphase compris es porphyritic protolithionite granites of the upper stock, and the se cond subphase includes zinnwaldite granites of the lower (main) stock. The age of the granites of the lower (67 Ma) and the upper (73.2 Ma) stock was determined for the first time by the Rb-Sr isotope method. T he rare-metal granites crystallized from a magmatic melt enriched in f luid, rare alkalis, and ore-forming elements. The rare-metal granites are derivatives of crustal melts. The tin-tungsten mineralization of t he Tigrinoe deposit is related to the granites and can be classified w ith mineral deposits of the cassiterite-quartz association, but it dif fers from similar ores from other regions by the wide occurrence of st annite, a high amount of varlamoffite in the oxidized zone, and low co ntents of sulfides and abundant topaz and lithium-iron micas. The tin mineralization of the greisen association is genetically related to th e rare-metal granites of the Tigrinoe deposit.