Postage stamps and postal history of Costa Rica change in currency from "Reales" to the new Pesos and "Centavos", the issue of 1863 was surcharged with new values for postal use: 1 Centavos, 2 Centavos, 5 Centavos (all over the Medio Real stamp), 10 Centavos (over Dos Reales) and 20 Centavos (over Cuatro Reales). The 5, 10 and 20 Centavos were also surcharged "U.P.U." Costa Rican stamps were issued overprinted "Guanacaste" in 1885-89 following war with Nicaragua over the sovereignty of Guanacaste. The first issue in the new "Colón" currency was dated 1900 and put into circulation in 1901. It consists of ten stamps with values ranging from
History of Chinese currency system that was not backed by silver or gold. The currency issued by the Yuan was the world's first fiat currency, known as Chao. The Yuan government attempted to prohibit all transactions in or possession of silver or gold, which had to be turned over to the government. Inflation in 1260 caused the government to replace the existing paper currency with a new one in 1287, but inflation that resulted from undisciplined printing remained a problem for the Yuan court until the end of the Dynasty. The early Ming dynasty (, 1368–1644) also attempted to use paper currency in the