Moessbauer study of natural pyrrhotites

The natural pyrrhotites from the Lake Victoria Goldfield in Tanzania have been studied by Moessbauer spectroscopy and the X-ray diffraction technique. Of the eight iron sulphide samples studied, four were found to be mostly monoclinic pyrrhotite and the other four were found to be mostly hexagonal or intermediate pyrrhotite. The Moessbauer spectra of both monoclinic and hexagonal pyrrhotites were best fitted with four sextets. A discussion on the determination of the Fe-sites in the pyrrhotites is presented.