A study of the calcination and sintering processes of 0.5PMN-0.5PFN ceramics prepared starting from the specifically designed precursor compound [Fe-0.6, Mg-0.4] NbO4, is presented. The microstructural characteristics are determined using X-ray diffraction and scanning electron microscopy. The resulting dielectric properties of the PMN-PFN samples thus obtained were very good when compared with those reported in the literature, for samples prepared at higher calcination temperatures. The dielectric properties as functions of temperature and the hysteresis loops (P vs. E) under different external applied electric fields are reported. (C) 2003 Kluwer Academic Publishers.