Nickel Coins have been in circulation in the United States since 1866. The metal composition and size of these coins have not changed in over 140 years! The nickel has maintained excellent resistance to wear while in circulation. The composite is .750 copper, .250 nickel. With just 25% of the content being nickel this makes the coin appear gray or silvery instead of with a copper appearance.
The many years of resisting wear and remaining silvery in color is one of the major reasons why the U.S. Mint chose the nickel-clad dime, quarter, half dollar and the dollar to be made in this way. It eliminated the valuable silver content but maintained the silver-like look.