Three groups of sources of ore matter are: (1) juvenile, related to subcrustal basaltic matter; deposits of Fe,Mn,V,Ti,Cr,Pt,Cu, and Zn in direct or close association with parent igneous rock, and with compositions similar irrespective of ore province; (2) assimilated, related to palingenetic granitic magma of crustal origin; these deposits (Sn,W,Be,Li,Nb,Ta) are less closely related to parent rocks and less uniform from province to province; (3) filtrational, involving circulation of nonmagmatic underground waters, e.g., telethermal suites. Deposits from juvenile sources belong to the early stage of geosynclinal development and are in and adjoining the troughs; crustal deposits are formed in central uplifts of geosynclinal belts during intermediate and late stages; telethermal deposits are typical of late geosynclinal or platform stages. Isotopic compositions of minerals in juvenile deposits have narrow ranges, in crustal deposits larger ranges, in telethermal deposits maximum ranges.

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