Front and side profiles of a 'Da Yuan Tong Bao' bronze 10 cash coin, 41mm in size, with Mongolian Seal script, cast in 1310 AD during the reign of Yuan Dynasty Emperor Wu Zong (元武宗) 1308-1311 AD in Mongol seal-writing. Reverse: blank. This coin is said to have been first cast in the 3rd year of Zhi Da (至大) reign (1310 AD). These coins tend to be crudely cast, often with casting holes in the fields, and attractive specimens are scarce and command a premium. S1099/FD1733.