Beneficiation of low-grade pyrite from Amjor, Bihar

A pyrite sample assaying 43.6 percent sulphur and 40.21 percent Fe and containing shale, melanterite and limonite as the principal gangue minerals was subjected to beneficiation tests. Tabling the-35 mesh ore followed by flotation of the table tailings produced a combined concentrate assaying 46.23 percent S with a total recovery of 94.8 percent. Straight flotation of the ore at pH 4.4 using ethyl xanthate and pine oil gave a concentrate assaying 46.9 percent S with a recovery of 93.6 percent. Under similar conditions amyl xanthate gave a similar concentrate but a slightly lower recovery. Though high recovery was obtained in all the tests, the grade of primary concentrate could not be one reflotation is expected to raise the grade to 48 percent.