Beneficiation of manganese ores with particular reference to the treatment of a low grade ore from Viti Levu, Fiji

Abstract

Summary Because of the increasing demand for manganese and the depletion of high-grade deposits considerable attention is now being directed at beneficiation of low-grade manganese ores. Most manganese ores due to their complex mineral association and their variable physical characteristics present many beneficiation problems some of which cannot be overcome satisfactorily. The manganese deposits of Fiji are becoming increasingly important but before many of them can be exploited a cheap beneficiation process will be required. Test work on a sample of ore from a low-grade deposit in S.W. Viti Levu showed that a marketable manganese concentrate could not be produced from this ore by gravity concentration or flotation even though a low manganese recovery may be acceptable. The poor metallurgical results were due to the reasons mentioned above and because the ore contained an appreciable percentage of iron oxides. Iron oxides and manganese oxides have very similar physical and chemical properties and therefo...