A nearly euhedral inclusion was observed in an electron microprobe survey focusing on minor minerals in the chromite-bearing ophiolite complex from southeast of Iran. According to properties such as zoning and homogeneity, investigated with a Field Emission Secondary Electron Microscope (FESEM), the inclusion is a homogeneous alloy grain. According to energy-dispersive X-ray (EDX) the grain consists of 41.5–43.0?wt.-% Fe, 28.6 to 31.3?wt.-% Ru, 18.0 to 19.7?wt.-% Os, and 9.1 to 9.5?wt.-% Ir with an average compositional formula of Fe0.422Ru0.298Os0.187Ir0.093. This is the first PGE alloy minerals of such composition found in Iran's ophiolites. Published PGM-bearing alloys of this kind are known as hexaferrum. The aim of the present study is to check the chemistry and zoning of the detected PGM alloy, to discuss its chemical composition and to compare the results with those other hexaferrum occurrences described in literature.
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