Beneficiation of Fluorspar from Thurwali, Rajasthan

Abstract

A sample of fluorspar received for beneficiation from the Director of Mines & Geology, Rajasthan, assayed 22.5% CaF2, 64.65% SiO2, 1.75% CaCO3, 4.3% Al2O3, 2.7% Fe2O3, 0.04% Pb, and 0,20% S with minor amounts of quartz and calcite. Fluorspar was fairly liberated from the gangue at about 100 mesh size. Flotation employing sodium oleate-oleic acid emulsion as collector and sodium silicate as gangue depressant at 9.5pH, followed by 2 cleanings of the rougher cleanings of the rougher float could yield a refloat concentrate of metallurgical grade assaying 85.1% CaF2, 6.9% SiO2, 3.8% CaCO3, 0.03% Pb and 0.23% S, with a recovery of 88.3% CaF2. Better grades of concentrate could be obtained by more cleaning operation.