We have deposited the Mössbauer isotope Fe 57 on (111) Si surfaces at room temperature and measured the Mössbauer spectrum using conversion electron Mössbauer spectroscopy for enhanced surface sensitivity. Samples were examined as a function of substrate preparation and thermal anneal. Rutherford backscattering was used to monitor sample preparation. The Fe 57 layers have been coated with natural iron (2.2% Fe 57) or silver to prevent them from oxidizing when exposed to air. The known distinctive Mössbauer spectra of Fe, FeSi, FeSi 2 , Fe in Si, and Si in Fe allows the identification of these phases in the samples.