Postage stamps and postal history of Mexico The regency had previously changed the official currency under which one peso equaled 8 reales to a decimal system in which one peso equaled 100 centavos. In making the conversion postal rates were rounded up, for example, the rate of one real being equal to 12.5 centavos was rounded up to 13 centavos. The stamps, as a result, were issued in values of 7c, 13c, 25c, and 50c. These stamps were issued with the year and invoice number and with or without the district name, but some issued in exchange for Eagle stamps were issued only with the Mexico City
Chinese cash (currency unit) The "wén" was one of the chief units of currency in China and was used to denominate both coins and paper money. Other denominations were used, including various weights, based on the "tael" system, for sycee silver and gold ingots. Until the 19th century, coins denominated in wen were cast, the most common formation being the round-shaped copper coin with a square or circular hole in the centre. The hole enabled the coins to be strung together to create higher denominations, as was frequently done due to the coin's low value. The number of coins in a string of cash