Cho Son Tong Bo

Diameter 24.2 mm
Obverse: Cho Son Tong Bo - Legend of first coin (1423 a.d.) of the Korean Joseon Dynasty (1392-1910 a.d.). King Yi Do (1419-1451 a.d.)
Weight was fixed at 150 coins to 1 Kun (600 g)

Reverse: plain

Edgar J.Mandel, Cast coinage of Korea, 1972. #10.3

Diameter 23.9 mm

Any additional comments on that coin would be appreciated. You can sent it to Vladimir Belyaev .
Chinese coinage website