Beneficiation of low grade Fluorspar from Chandidongri Mines, Drug, Madhya Pradesh

A fluorspar sample from Chandidongri Mines, Madhya Pradesh, was received from the Director of Geology and Mining, Government of Madhya Pradesh, for beneficiation tests. As received, the sample assayed 46.25% CaF2, 49.68% SiO2, 0.68% Pb, 0.33% Fe2O3, 1.05% Al2O3, 0.12% S and traces of CaCO3, Zn and Ba. Quartz, constituting about 50% by weight, was the principal gangue mineral and was intimately associated with fluorspar. Small amounts of Cerussite, galena, ochre, feldspar and clay were also present. Hydraulic classification followed by tabling of the ground sample, produced a combined concentrate assaying 83.81% CaF2 with only 35.6% CaF2 recovery. Flotation of lead employing xanthate followed by fatty acid flotation of fluorspar produced a lead float assaying 15.15% Pb with a recovery of about 82.5% Pb in the product. Four cleanings of the fluorspar rougher float yielded a fluorspar refloat concentrate assaying 96.6% CaF2, 0.06% Pb, 3.6% SiO2, 0.1% Fe2O3 and traces of S, with a recovery of 77.9% CaF2 in the product. By repeated cleanings, it should be possible to further reduce the silica content to yield a refloat concentrate confirming to the specifications laid down for chemical and ceramic grades of fluorspar.