 Silver then started to occupy a paramount place in the Mongol economy and was supplemented by government issued paper money.Under the reign of Kublai Khan the Zhongtong Jiaochao (中統交鈔) was issued whose value was based on the fabric silk.Under the reign of Külüg Khan in the year 1308 the Zhiyuan Baochao (至元寶鈔) was issued which was supplemented with the silver-based Zhida Yinchao (至大銀鈔), but these circulated only for a year.