Metal coins are died copper, brass or casted from zinc alloy. They have different   sizes, are covered with gold, silver, brass, nickel, black nickel, chromium, copper plating (The metal platings).  The surface of the coins is polished, mat (opaque), with texture or antiqua (raised areas are lighter and recessed areas are darker). They can be with relief (2D or 3D engraving) or covered with colour enamels (The producing technology). Coins can have computer – laser made custom engravings and be packed in special boxes (Boxes for medals).