This product is used for external alchemy. It is lead-powder for facial application or painting, also known as "Shaofen". Its chemical composition is PbCO₃. The "Shiming·Shishoushi" states: "Lead-powder: Hu, meaning paste, is mixed with fat to apply on the face." Alchemists refer to it as Liudan Rigao. The "Sandong Zhunang" Volume 4 "Shen Dan Xian Yao Ming Pin" mentions: "Liudan Rigao, the oral tradition says it is lead-powder." It is also known as tin powder, Dan Rehmannia, Liudan, Jiexi coarse, Quefen, Liudan Baihao, and Bai Gao (see Shiyao Erya·Explanation of Hidden Names of Various Medicines). Another name is red lead, a cosmetic.