Resolution of the iron sites in the Mössbauer spectra of Ca-Fe pyroxenoids is only partial, two doublets being apparent in each case, whereas there are up to nine cation sites in each structure. Thus the inner and outer doublets represent, respectively: two sites and two sites in Ca
0.5Fe
0.5SiO
3 (ferrobustamite); five sites and two sites in Ca
0.15Fe
0.85SiO
3 (pyroxferroite); and five sites and four sites in FeSiO
3 (ferrosolite III). Disorder of iron and calcium which exists in the two calcium-bearing pyroxenoids is not readily apparent in the spectra.
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