The currency unit was changed from hwan to won under the currency reform carried out in 1962, and the circulation of hwan-denominated currency was prohibited. However, 50-hwan and 10-hwan coins remained in circulation for small value transactions. To replace these coins, Bank of Korea issued three won-denominated coins (10-won, 5-won, and 1-won coins) for the first time in 1966. The 1-won and 5-won coins took the same design theme of Mugunghwa and Geobukson, used in 10-hwan and 50-hwan coins, respectively. For the 10-won coin, the stone pagoda, Dabotap, was newly adopted as a design theme. As the copper price surged, the material of the 1-won coin was changed into aluminum in 1968.