Emperor Xian Feng (咸丰，AD1851-1861), Qing Dynasty. Big brass coin valued 100 wen, with mint mark Su on reverse.

The big brass coins of Xian Feng form a huge and amazing series; because he is the only emperor who issued large coins with face value higher than 10 wen. The great Tai Ping Tian Guo (太平天国) rebelion happend during his reign. The whole south China were in war state and the copper supply routes were cut off. Since many mints were short of metal material, the emperor gave them right to cast high-face-value coins.