Microscopic and X-ray diffraction studies on two natural specimens of two-phase hexagonal pyrrhotites show that the two unmixed phases have a common crystallographic orientation. In polished section, the common c-axis is in the same plane as the short diagonals of the rhombic sections formed by the intersection of the exsolution lamellae. The superstructures of the intermediate hexagonal pyrrhotite in the two samples are different from one another and have not been reported previously from natural material, being hexagonal 2A,6C and hexagonal 2A,4C, where A and C refer to the a and c parameters of the subcell.

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