Mitsubishi Materials Group (MMCG) promotes the processing of E-Scrap at Naoshima Smelter & Refinery (Naoshima) and Onahama Smelting & Refining Co., LTD in Japan. The increase in E-Scrap treatment amount makes the kinds and amounts of metals enter the process of copper and precious metals smelting increase. Lead, bismuth, antimony, and tin are impurity metals for copper smelting and refining and precious metals smelting. Therefore, it is important to extract impurity metals and recover them as valuable metals for expanding the E-Scrap business. Hosokura Metal Mining Co., LTD (Hosokura) is the only lead smelter & refinery of MMCG. Hosokura has received lead residues from copper smelting and precious metal smelting at Naoshima, and Hosokura has recovered lead, bismuth, antimony as products, and gold, silver as crude silver. However, Hosokura was not able to recover tin from lead refinery process, and part of tin contained in copper matte was returned to Naoshima. In 2018, the tin recovery process was developed by Mitsubishi Materials Co., LTD (MMC). In the process, tin is recovered as burtite (CaSn(OH)6) from Harris dross. The recovered burtite is sent to MMC’s Ikuno Plant (Ikuno) that produces electrolytic tin. In July 2020, Hosokura started operation of the plant to recover burtite from Harris dross, and in August began sending the burtite to Ikuno. This report introduces the newly started tin recovery business of MMCG.