Early Roosevelt dimes were made of 90% silver and 10% copper (1946-1964). Dime pieces from 1964 forward are clad coinage consisting of copper sandwiched between two layers of an alloy that is 75% copper and 25% nickel.
Beginning in 1992, silver coins were included in yearly collectors sets produced by the US Mint. These 90 percent silver proof coins include the Roosevelt Dime, Washington Quarter and Kennedy Half Dollar.