Sumitomo Metal Mining Co Ltd has three core operating segments, namely mineral resources, smelting and refining, and materials. The mineral resources business is engaged in exploration, development, production and sale of non-ferrous metals, primarily in Japan. The smelting and refining segment which generates the majority of group revenue, smelts and sells copper, nickel zinc, lead gold and others, and manufactures and sells stretched copper products and special steel castings. The materials division manufactures semiconductor materials, battery materials, bonding materials, aerated light-weight concrete, chemical catalysts among others.