. . . "ides, manganese oxides, molybdenum oxides, nickel oxides, vanadium oxides, tungsten oxides, and rare-earth metal oxides, and similar components, and also consisting of compounds such as carbonate, sulfate, and hydroxide, and similar compounds, transformable into oxides after a heat treatment such as aluminum oxides, silicon oxides, magnesium oxides, calcium oxides, strontium oxides, barium oxides," .