Wolframoixiolite in lithium-fluoric granites of the Arga-Ynnakh-Khaysky massif, Yakutia

For the first time, lithium-fluoric granites and ongonites of the Arga-Ynnakh-Khaysky massif (East Yakutia) have been revealed to contain an accessory complex of tungsten-bearing tantalum-niobates  ( columbite-(Fe), columbite-(Mn), tantalite-(Mn), minerals of microlite group, tantalic rutile )  including «wolframoixiolite». These rocks containing wolframoixiolite, their composition and typomorphic features are described: they are highly ferriferous, with major geochemical role of niobium and wide variations of tungsten and tantalum concentrations. Wolframoixiolite occurs there in paragenesis with tungsten-bearing columbite-(Mn), tantalum-niobium ferberite, lepidolite and topaz. Wolframoixiolite of the Arga-Ynnakh-Khaysky massif was formed on a late-magmatic stage of lithium-fluoric granites crystallization by polymorphic transformation of columbite-(Fe). The study of accessory mineralization in rare-metal granites of Eurasia allows, taking into account a new find, to draw a conclusion, that wolframoixiolite is typomorphic accessory mineral in lithium-fluoric granites and may be looked as the indicator of rare-metal-granite magmatism with accompanying tin-rare-metal ore mineralization.