Electron Microprobe Mapping as a Tool in Ilmenite Characterisation

Abstract The demand for accurate mineralogical data is increasing rapidly as exploration methods, prospect evaluation procedures and metallurgical optimisation studies become more sophisticated. in response to these needs, semi-automated and automated image processing systems which detect minerals using optical microscopy, scanning electron microscopy or electron microprobe microanalysis (EPMA) are becoming increasingly important tools in the exploration, mining and mineral processing industries. CSIRO Minerals has developed an EPMA based imaging (or mapping) method for characterising ilmenite concentrates. The method uses a JEOL 8900R EPMA to collect elemental x-ray maps which are then processed using in-house developed software, Chimage. The mapping procedure differs from traditional automated identification systems in that no detailed a priori knowledge of the mineral phases is required. in addition, Chimage software enables complete processing and interpretation of the data set off-line. Elemental data can be displayed in either scatter or ternary diagrams showing clusters which allow mineral phases to be identified.