Ming Dynasty. Da Zhong Tong Bao, 1371-1398, AE 2 Cash (4.6 g, 26 mm). Mintmark \Bei Ping\ on back. Third coinage started in 1371 (Year 4 of Hong Wu), during the reign of Zhu Yuanzhang, the first Ming Emperor. Pleasing greenish and rusty patina on both sides. Very rare mintmark for the denomination.