The selective flotation of galena from sphalerite with special reference to the effects of particle size

Abstract The selectivity of galena flotation from a synthetic mixture with sphalerite and quartz and from a typical Broken Hill ore has been determined. It was found that the selectivity was limited by the relative flotabilities of coarse galena and sphalerite of intermediate sizes. The use of split conditioning in the preparation for flotation resulted in significant improvements in lead-zinc selectivity for both samples. By contrast the use of conventional zinc depressants in the flotation of the ore resulted in only slight changes in the behaviour of the minerals and had no discernible effect on the selectivity.