One can identify different types of Mexican coins by looking on the back of the coin to determine which coin type it is. The back of the coin typically names the value of the coin. Additionally, the size of the coin serves as an indication of the value of the coin.
Like United States currency, the Mexican peso is traded by decimal values. Coins have values such as 0.05 peso, 0.10 peso, 0.20 peso and 0.50 peso. A coin valued at one-hundredth of a peso is a centavo, similar to a U.S. penny. Unlike U.S. coins, there are also coins for full peso amounts. There are 1-peso, 2-peso, 5-peso, 10-peso and 20-peso coins. The 10-peso and 20-peso coins are the only ones that don't have currency values written on the back. Mexico also uses paper currency of various values, but these currencies are not highly traded.
Historic Mexican currency may be more difficult to identify. Over the past two centuries, many different coin values have existed. These include 2.50-peso coins, 1-centavo coins, 25-centavo coins and 2-centavo coins. These coins are made of different materials, including silver, gold, bronze and highly valuable .903 silver. Different materials were used during various time periods, so investigating the time periods in which certain materials were used often makes it possible to determine a coin's age.