Korea, Joseon Dynasty. Sang Pyong Tong Bo; 1 Mun. Military Training Command. 1757. (3.78g; 23.9mm). O./ 常 平 寶 通 [Sand p'yong tong bo; Department of Korean Yi Dynasty, currency unit]. R./ 訓 大 五 [(Hun):Hullyondogam Military training Command, (Tae): Great, (Wu) Series/Furnace 5]. Mandel#28.5.5. $20