Between the twelfth and the fourteenth centuries China’s monetary system shifted from a multiple currency system including paper notes, bronze coin, and uncoined silver to a unified paper currency system established by the Mongol Yuan dynasty. Consequently, China’s longstanding bronze coin standard was replaced by a new money of account denominated in silver. However, silver largely disappeared as a medium of exchange under Yuan rule. Instead, silver units of account were used to denominate paper currency. The monetary policies of the Mongol Yuan state established a silver unit of account that remained the monetary standard throughout China’s late imperial era.