Floatability of apatites and gangue minerals of an igneous phosphate ore

The presence of different apatite types is characteristic of igneous phosphate deposits. The flotation performances of primary and secondary apatites occurring in phoscorites, weathered phoscorites and pyroxenites were investigated. As a contribution towards the understanding of the behaviour of the flotation system, the major gangue minerals were also selected for the study: quartz, a pyroxene (augite), altered micas (vermiculite), calcite and dolomite. Zeta potential curves for all the above mentioned mineral species were determined as a function of pH, pCa and pMg. Microflotation experiments were performed in a modified Hallimond tube at different pH levels in the presence of sodium oleate as collector and corn starch as depressant.