Gresik Smelter & Refinery is performing smoothly and has established a new standard for environment-friendly, high-efficiency copper smelting and converting technology, PT. Smelting applies Mitsubishi technology for copper smelting process. The Mitsubishi process is copper continuous smelting and converting technology using three furnaces. The three furnaces are linked with covered launders, through which all the molten materials are continuously transferred by gravity.