Euro coins edge of the €2 coin also protects it from counterfeiting. Euro coins were designed in cooperation with organisations representing blind persons, and as a result they incorporate many features allowing them to be distinguished by touch alone. In addition, their visual appearance is designed to make them easy to tell apart for persons who cannot read the inscriptions on the coins. The coins increase in size and weight with value. Of the eight denominations of euro coins, the three lowest denominations are small, resemble copper in colour and are quite thin and light. The next three denominations resemble gold in
Euro coins as long as they are in an irregular denomination, so it invented a €2.5 coin. The European Central Bank closely monitors the circulation and stock of the euro coins and banknotes. It is a task of the Eurosystem to ensure an efficient and smooth supply of euro coins and to maintain their integrity throughout the eurozone. As of Sep 2018, there are approximately 130 billion coins in circulation around the eurozone. In contrast the USA has minted over 300 billion pennies since 1983 when the current copper-plated zinc metallic composition began. Using a population of 339 million for the EU