Thermal decomposition of iron(II) acetate, Fe(CH3COO)2, and iron(III) acetate hydroxide, FeOH(CH3COO)2, has been studied using57Fe Mössbauer spectroscopy and X-ray diffraction. Samples were thermally treated in air atmosphere between 150°C and 1000°C. The formation of maghemite '-Fe2O3, and hematite,
-Fe2O3, is discussed. Hematite appears as the final decomposition product.