Korean currency
The yen was the currency of Korea during the Colonial rule, from 1910 to 1945, and was issued by the Bank of Joseon It was equivalent to the Japanese yen and consisted of Japanese currency and banknotes issued specifically for Korea. It was replaced by the South Korean won at par in 1945, and by the North Korean won in 1947.
Superdollar
It has been confirmed that North Korea has passed off superdollars (Korean: "kattalio") in various countries. The counterfeit bills also circulate both within North Korea and around its border with China. There is, however, some doubt about the reliability of North Korean defectors' claims, on which the United States partially bases its accusations, along with South Korean intelligence sources.