Аннотация
Within the Altai-Sayan fold region, covering the territory of the East Tuva Highlands and Eastern Sayan, one of the richest rare metal provinces of Russia is concentrated. Deposits of rare metals, elements and lands formed within its limits have different ages and arose in different geotectonic environments and in different metallogenic eras. They are associated with the introduction of alkaline rock masses that are common along the fault system between the caledonids of the Altai-Sayan fold region and the Tuvino-Mongolian Precambrian superterrane. Their distribution range is also defined as the East Sayan rare metal metallogenic zone (VSMZ), which arose due to the impact of mantle plumes on the southwestern framing of the Siberian platform. Geochemical and geochronological studies were carried out at the Ilei fluorite-phenakite ore show. Ore development resulted from the introduction of Ognite complex granitoids into the limestones of the Mongoshin formation, which became a geochemical barrier to the igneous fluid enriched with fluorine and Be. Geochronological Rb-Sr and Ar-Ar studies have shown that subalkaline granites, as well as acidic volcanites of the Ilean sequence, are of Middle Devonian age ~ 390 million years, which is consistent with age estimates for the rocks of the Ognite complex. Thus, the same age of magmatism and ore formation at the Ilei ore phenomenon indicates the contribution of Devonian magmatism to the formation of rare metal mineralization within the VSMZ.