Sintered plates of alumina have been implanted at room temperature with 1.2 × 10 17 57Fe +/cm 2 at 110 keV. Rutherford backscattering spectrometry and conversion electron Mössbauer spectrometry have been used to characterize respectively the depth distribution and charge states of iron. A theoretical approach of the as-implanted iron profile has been carried out by using a modified TRIM code which takes into account the fluence, the sputtering effects and the modification of the surface composition during ion bombardment. The iron profile and charge-state evolutions after isochronal air annealings from 200° C to 1600° C have been investigated. Correlations with the surface topography evolution investigated by SEM are proposed.