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
1 euro coin coin a two-colour appearance. The coin has a diameter of 23.25 mm, thickness 2.33 mm and a mass of 7.5 grams. The coins' edges consist of alternating segments: three smooth, three finely ribbed. The coins have been used from 2002, though some are dated 1999, which is the year the euro was created as a currency, but not put into general circulation. The reverse (used from 2007 onwards) was designed by Luc Luycx and displays a map of Europe, not including Iceland and cutting off, in a semicircle, at the Bosphorus, north through the middle of Ukraine, then Russia and