Mitsui Mining Co Ltd. The Group's principal activity is the coal mining. The Group also deals with construction materials, chemical and environmental machinery, transportation, real estate, leisure facilities and other retail operations. The Group's fuel products include coal, coke, petroleum and other fuel products. Machinery segment includes chemicals, environmental and other industrial machinery. Fuels accounted for 45% of fiscal 2002 revenues; construction materials, 28%; machinery, 12%; transportation, 4%; leisure, 3%; real estate, nominal and other, 8%.