A clad coin is one formed from layers of more than one metal. U. S. half-dollars, quarters and dimes have all been clad since 1965.
Prior to 1965, half-dollars, quarters and dimes all contained approximately 90 percent silver. Once the change was made to clad coins, silver stopped being used in their manufacture. Instead, they have a copper core surrounded by outer layers made primarily of nickel. Holding the coin from the side allows visualization of these layers. Golden dollar coins are clad, with a copper core and outer layers of a mixture of other metals. Silver was removed from five-cent pieces beginning in 1866, when nickels began to be made of copper and nickel. Pennies are made of copper-plated zinc.