5 Won Blue stamp; non-convertible (Socialist) currencies, 2nd issue

The 1978 North Korean currency reform introduced a dual-currency system that separated foreign visitors from the domestic economy — but by 1986, the regime had gone further, subdividing the visitor-facing currency itself by nationality. Notes for socialist-bloc visitors were overprinted with a blue stamp, while capitalist-country visitors received red-stamped equivalents at a punitive exchange rate. This note belongs to the socialist tier: theoretically exchangeable at parity with the domestic won, but still barred from use in ordinary North Korean shops.

The system effectively quarantined foreign currency flows into state-controlled dollar shops. It collapsed quietly in the 1990s as the Soviet subsidy network disintegrated.