20 Won World's First Metal types for printing

The movable metal type referenced here predates Gutenberg by approximately two centuries. The Goryeo dynasty cast individual bronze type characters no later than the early 13th century, with the Jikji — a Buddhist anthology printed using this method in 1377 — surviving as the oldest extant book produced with movable metal type, held today at the Bibliothèque nationale de France. North Korea's claim to this heritage is politically loaded: the relevant history belongs to a unified Korean past that both Pyongyang and Seoul actively compete to own.