Polycrystalline α-Al2O3 samples have been implanted by 1017 Zr, Fe or Cu ions/cm 2 at 110 keV in order to form oxide precipitates in the near-surface region after annealing in air. A chemical and microstructural characterization has been performed on the as-implanted surface and on the samples annealed in the temperature range from 600 to 1600°C. The nature of the chemical phases and the precipitate evolution have been characterized by combining RBS, XPS, GXRD, CEMS, TEM and SEM techniques. XPX, CEMS and TEM experiments on as-implanted specimens detect copper, iron and zirconium as Cu° (small metallic precipitates), Fe° (small α-iron precipitates), FeII (associated with FeAl2O4), and FeIV (metastable state), Zr° and ZrIV (ZrO2) in the as-implanted region. Analyses carried out after heat treatments between 600 and 1000 °C indicate a complete surface oxidation in this temperature range. Additionally, some precipitates appear along grain boundaries. Annealing at temperatures ranging from 1000 to 1600°C leads to drastic surface composition changes. The stability and size of the different observed precipitates (ZrO2, AlFeO3, Fe2O3, Fe3O4, CuO, CuAl2O4) strongly depend on the annealing temperature.