Mitsui Kinzoku Company, Limited engages in the manufacture and sale of metal products in Japan and internationally. It operates through Engineered Materials, Metals, Mobility, and Other Businesses segments. The company offers engineered powders, including ultra-fine powders for electronic materials, powder metallurgy, and solder powders; rare metals, such as tantalumu and niobium oxides and carbides, and cerium oxide abrasives; battery materials comprising hydrogen storage alloys and lithium manganese oxides; catalysts; copper foils; PVD materials; and ceramics for electronic components. It also provides side and back door latches, hood latches, etc. for automobiles; perlite for processing and cooling; Nenisanso, a soil improvement material; and ROKAHELP, a perlite-based filter aid. In addition, the company smelts and recycles nonferrous metals consisting of zinc, zinc base alloys, lead, tin, antimony trioxide, copper, gold and silver, and sulfuric acid; explores for copper and zinc ores; operates geothermal power plant; and provides resource development and environmental protection engineering services. Further, the company offers zinc and lead ingots, zinc sulfate, zinc raw materials, and sulfuric acid and plaster products; chemical products; optical crystals, scintillators, and radiation detectors; rolled copper foil products. Additionally, it engages in the mechatronics and corrosion prevention businesses; handling wires and cables activities; and provision of engineering services and IT systems. The company was formerly known as Mitsui Mining & Smelting Co., Ltd. and changed its name to Mitsui Kinzoku Company, Limited in October 2025. Mitsui Mining & Smelting Co., Ltd. was incorporated in 1950 and is headquartered in Tokyo, Japan.