Granular films of nominal composition (Fe,Co,Ni)50(SiO2)50were prepared by rf sputter deposition and characterized by transmission electron microscopy. In each case the films were found to consist of small metal particles, several nanometers in size, embedded in an amorphous silica matrix. The chemical composition of the metal particles was studied, for the first time, by x‐ray photoelectron spectroscopy. These measurements detected the presence of the metal oxides Fe3O4, FeO, Fe2O3, CoO, NiO, and Ni2O3associated with the Fe, Co, and Ni particles, respectively.