Recovery of Diamond and Concentration of TiO2 from-20 Mesh Fraction of Diamond Ferrous Tuff from N.M.D.C

Abstract

A sample of -20 mesh fraction of diamondiferous tuff was received from the Chief Engineer, Panna diamond project, N. M. D. C. Panna, M. P., for studying the possibilities of recovering diamonds and upgrading the sample with respect to Ti02. The sample as received assayed only 1. 7% Ti02. Jigging and tabling tests were conducted to obtain a pre-concentrate of heavy minerals. Magnetic separation of the heavy mineral. Magnetic separation of the heavy concentrates produced magnetic fractions assaying only 3.1 to 3.35% Ti02. The non-magnetic fraction was subjected to electrostatic separation. No diamond grains could be identified in the non-conducting fraction Rutile, being present in minor amounts, could not be separated by electrostatic separation, The tailing fraction carried 80, 7 to 83, 1% of the total Ti02 in the product. Most of the Ti02 in the sample was contributed by minor amounts of leucoxene as minute inclusions in the serpentine and calcite grains. Hence the Ti02 content in the tailing could not be concentrated by electrostatic separation. Flotation of the sample after flash grinding to about -65 mesh size using 1ight diesel oil and pine oil could not recover any diamond grain, Flotation tests to separate Ti02 bearing minerals from gangue did not yield satisfactory results.