 Before the Mongol Empire conquered China the Jin dynasty also issued paper money.Before the establishment of the Ming dynasty the Mongol Yuan dynasty had suffered from a severe case of hyperinflation which made the paper money issued by them worthless.Under the reign of the Yuan dynasty copper cash coins remained in circulation with the inscriptions Zhida Tongbao (至大通寶), Dayuan Tongbao (大元通寶), and Zhizheng Tongbao (至正通寶) forming the majority of the circulating issues and "strings of cash coins" remaining a currency unit.