China, 1078-1085 AD., Northern Song dynasty, emperor Shen Zong, 1 Cash, Hartill 16.225.

China, Northern Song dynasty (960-1127 AD.), emperor: Shen Zong (Shen Tsung) (1068-1085 AD.), reign title: Yuan Feng (1078 - 1085 AD.), issued 1078-1085 AD.,
1 Cash (25-25,5 mm / 3,57 g), bronze, cast, square center hole, bigger module, braod rim,
Obv.: ( 元 豊 通 寳 ) , Yuan Feng Tong Bao (Yuan Feng T'ung Pao) , clockwise, seal script, squarish Bao.
Rev.: plain (square center hole). (crescent below?)
Hartill 16.225 (rarity 15, very common) ; Schjöth 543 var. ; for similar Japanese imitations cf. http://www.history.ucsb.edu/faculty/roberts/coins/Nagasakiexport.html .