Japan’s Showa Denko plans to build a chemical alumina plant in West Kalimantan, Indonesia, in partnership with Indonesian mining firm Antam. Expected to cost an estimated $450 million, the plant will have capacity for 300,000 metric tons per year. Showa Denko will take two-thirds of the output, and Antam will take the balance. After the plant opens in 2014, Showa Denko will close a 200,000-metric-ton chemical alumina plant in Yokohama, Japan. Chemical alumina is used for applications such as water treatment and electronic materials.