Evidence of Epithermal Activity and Gold Mineralization in Newania Carbonatite, Udaipur District, Rajasthan

The geological, geochemical and C- and Pb-isotopic evidence available on the Newania Carbonatitic Body (NCB) in southern Rajasthan are not entirely incontrovertible from the point of view of carbonatite magmatism. Based on recognition of calcite-lined vugs, 'dog-tooth spar' and 'jig-saw puzzle' structure, the hematite bearing ankeritic carbonates (the ankeritic 'carbonatite') are considered as epithermal emplacements into dolomitic (magnesio-) carbonatite. Seven samples collected from hematite bearing ankeritic (±sideritic) carbonates, which constitute an important component of the NCB, have given gold values ranging between 0.93 to 1.36 ppm. The significance of this find lies in the association of gold with oxides and carbonates of hydrothermal affinity.