Mössbauer spectroscopic study of some iron and antimony – containing minerals

Iron-57 Mossbauer spectra have been recorded from three minerals containing both iron and antimony. Schafarzikite of composition FeSb2O4 contains Fe2+. The 121Sb Mossbauer spectrum shows only the presence of Sb3+. The 57Fe Mossbauer spectrum corresponds with that recorded from a material of identical composition synthesised by a solid state reaction during the course of this work. Apuanite of formulation Fe20Sb16O48S4 contains both Fe2+ Fe3+ in the ratio 1:3.35 The result is consistent with crystal structure determinations and the formulation of apuanite as Fe42+Fe163+Sb16O48S4. Versiliaite of composition Fe12Sb12O32S2 contains Fe2+and Fe3+ in the ratio 1:2.12 and, also consistent with structural characterisations, can be formulated Fe42+Fe83+Sb123+O32S2.