We investigated the mechanosynthesis of gadolinium iron garnet by high-energy ball milling stoichiometry amounts of alpha-Fe2O3 and Gd2O3, followed by short thermal annealings conducted at moderate temperatures. X-ray diffraction and Mossbauer spectroscopy results revealed, for the as-milled samples, the formation of the GdFeO3 perovskite phase, in relative amounts that depend on the milling time. The formation of the Gd3Fe5O12 garnet phase was observed in 1000 degrees C/2 h or 1100 degrees C/3 h as-annealed samples. The occurrence of a milling time was verified in which the relative amount of garnet phase formed by further annealing is maximized.