Chon, generally referred to colloquially as Yopchon, is a Korean word, and a general term for any copper coin, circular in form, and having a square hole in the centre. The Chinese word is Ch'ien.

The Tang-bak-chon was a copper coin of Korea issued in the third year of the Em- peror Tai, i.e., A.D. 1866, for the purpose of making up the deficit in the funds for building the Kyong-pok palace. It bore characters meaning "worth a hundred", but having no such real value its use had to be forced upon the people, causing greal distress.

The Tang-au-chon was a copper coin issued in the twentieth year of the same Emperor, i.e., A.D. 1883. It had characters meaning "worth five"on the reverse and was put into circulation at the value of five of the older coins, but having no such real value and being similar in size with the larger varieties of the older coins, it was often used indiscriminately with the latter. For the silver pieces with enamel centres see Daidong Chun.

The modern copper Korean Chon is the equivalent and almost the counterpart of the Japanese Sen. In 1894 nickel two Chon five Fun pieces were issued in great quantities, and in 1897 silver ten and twenty Chons, nickel five Chon, and copper one and half Chons were issued.