The data were generated in two labotories of the Dalhousie University in Halifax during a series of experiments to determine the solubility of chromite in komatiite mixed with different crustal contaminants. The experiments were designed to determine the solubility of the mineral chromite in silicate melt, with the dominant variable being the silica and iron content of the melt.
After equilibrating chromite with melt at 1192-1430 degrees Celcius, samples were quenched and the composition of the chromite, quenched melt (now glass), and olivine run-products were measured for major and minor elements by electron microprobe, and the chromium concentration in the glass was measured by laser ablation ICP-MS. Analytical procedures are included in the associated data description file.
The data are provided in a series of Excel worksheets containing five data tables. Table 1 is a summary of the composition of the starting materials used in experiments. Table 2 is a summary of the conditions of temperature, oxygen fugacity, experiment duration and initial sample composition. Table 3 is a summary of the major and minor element composition of the glass measured by electron microprobe and laser ablation ICP-MS. Tables 4 and 5 are summaries of the major and minor element composition of the olivine and chromite, respectively, measured by electron microprobe.
The Bushveld Complex in South Africa is the world’s largest mafic layered intrusion by far and it contains more than three-fourths of the global reserves of platinum group elements (PGE) and more than one-third of global chromium reserves. All of the chromium and much of the platinum are hosted by layers of chromitite in the so-called Critical Zone, a stratigraphic interval of variable thickness (ca 1000 to 1500 m) in the lower third of the 7000-8000 meter-thick intrusion. The data presented herein result from the German-South African project AMREP (Applied Mineralogy for Research Efficiency of Platinum Metals), which investigated the feasibility of extracting PGE from chromitite layers that were mined for chromium at the Thaba Cr mine. The data comprise in-situ mineral analyses by electron microprobe (EPMA data), whole-rock chemical analyses of the platinum-group element concentration (PGE assay data), and microtextural analysis of thin sections to determine the grain size and size distribution of chromite in the layers (CSD data: crystal size distribution).