As a currency, silver was first found in a batch of empty silver cloth unearthed in the Spring and Autumn Period in the west gate of the ancient city of Fugou County, Henan Province, but there are few examples. In 65438 BC+065438 BC+09 BC, the Western Han Dynasty also cast "three platinum products", but "we can't abandon them after the end of the year". By the end of the Tang Dynasty and the Five Dynasties, silver had a tendency to enter circulation, and the folk circulation in the Song, Jin and Yuan Dynasties was more and more extensive. It developed into a common official currency in the middle of Ming Dynasty.