Late Paleozoic-Mesozoic high-alumina granites of Altai and their rare-metal specialization

The high-alumina content of Late Paleozoic-Mesozoic granites of Altai is re garded as a specific feature of their rare-metal specialization. The conten ts of alumina in various groups of granitoids and their correlation with th e contents of trace elements in these rocks are studied. Late: Paleozoic-Me sozoic rare-metal granite massifs in Altai contain normal nonplumasitic gra nites, which belong to an older complex. Part of this complex formed much e arlier than the high-alumina granitoids. The genesis of the high-alumina gr anitoids is interpreted.