Each numbered type listing will contain a description of the coins metallic content. The traditional coinage metals and their symbolic chemical abbreviations are:
During the 18th and 19th centuries, most of the world's coins were struck of copper or bronze, silver and gold. Commencing in the early years of the 20th century, however, numerous new coinage metals, primarily non-precious metal alloys, were introduced. Gold has not been widely used for circulation coinages since World War I, although silver remained a popular coinage metal in most parts of the world until after World War II. With the disappearance of silver for circulation coinage, numerous additional compositions were introduced to coinage applications.
Most recent is the development of clad or plated planchets in order to maintain circulation life and extend the life of a set of production dies as used in the production of the copper-nickel clad copper 50 centesimos of Panama or in the latter case to reduce production costs of the planchets and yet provide a coin quite similar in appearance to its predecessor as in the case of the copper plated zinc core United States 1983 cent.
Modern commemorative coins have employed still more unusual methods such as bimetallic coins, color applications and precious metal or gem inlays.