Watch List notes:

KOREA: Sejong, 1418-1450, AE cash (3.68g), H-10.3, cho son tong bo, orthodox script, cast from 1423-25, lightly cleaned, VF. Bronze coins were cast starting in 1423 during the reign of king Sejong the Great with the Joseon Tongbo legends. The Sejong era Joseon Tongbo cash coins were only issued in the years 1423 (Sejong 5), 1424 (Sejong 6), and 1425 (Sejong 7). The coins produced under Sejong were pegged to silver at 150 coins to one K?n which is equal to 600 grams, though the actual market rates regularly fluctuated. But the monetary system proved to be unpopular as people resorted back to barter after a few years.

Estimate: 75-100 USD