Mineralogical Analysis of a Chrome Ore from South Africa

The investigations on chemical composition, mineral composition, embedded figures, texture and microstructure of chrome ores were conducted systematically by various analysis methods such as chemical analysis, XRF, SEM, and MLA 650 system. The results showed that there are 92.66% chromite and a small amount of chlorite and forsterite as the main mineral compositions, the content of quartz is very low. Elements as Cr and Fe are almost all present in chromite. The content of Cr₂O₃ is 41.84% and Cr₂O₃/FeO is 2.1. The main elements in the chromite are Cr, Fe, Mg, Al, O; the main elements in the chlorite are Mg, Al, Si, O and a small amount of Fe; the main elements in the forsterite are Mg,Si and O. On the basis of clarifying the mineralogical characteristics, to produce high-grade alloy, this ore should not be separately put into the submerged arc furnace without pretreating. However, it also seems to be difficult to separate the gangue compositions by the conventional physical upgrading methods, such as magnetic separation and gravity separation. So, chemical mineral processing should be taken into account.