De-oxidation of Ag2O and ZnO powders has been accomplished by the mechanochemical process (MCP) using Si and Fe as reducing agents. Exception is the reduction reaction of ZnO with Fe since it involves a positive enthalpy, and so even after 300 h milling its reduction does not take place. A solid solution of nanosized Fe2O3 into an amorphous-like ZnO matrix is developed instead. In contrast to reduced products prepared by conventional thermal decomposition of oxides, a number of advantages are conferred into the MCP-synthesized Ag-SiO2, Ag-Fe2O3, Zn-SiO2 and ZnO-Fe2O3 submicrometre composite products, such as a homogeneous dispersion of active oxides into the reduced metal matrix and nanometre tailored particles.