Initially, the Washington Quarter was composed of 90% silver with 10% copper. By 1964, the price of silver had risen to where it would cost more than 25 cents to mint Washington Quarters. The Treasury Department switched to a clad composition consisting of an outer layer of 75% copper and 25% nickel with an entirely copper inner core.

In 1965 Congress passed the Coinage Act of 1965, which prohibited mintmarks on coins in an effort to keep collectors from removing the coins from circulation, As a result, the "D" was removed from Washington Quarters minted in Denver. Congress authorized adding the mintmark back to coins in 1968, though it was moved from the reverse to the obverse of the Washington Quarter.

To commemorate the Bicentennial of the signing of the Declaration of Independence, the Mint held a competition for new designs of the reverse of the Washington Quarter in 1974. Jack Ahr won the competition with a design showing a colonial drummer boy and torch of liberty. In addition to the redesigned reverse, a double-date "1776-1976" was added to the obverse. For the Bicentenial, a small number of silver clad coins, consisting of an exterior plating of 80% silver and 20% copper with an inner core of 20.9% silver and 79.1% copper were minted for collectors.

In 1999 a 50 State Quarters Program replaced the traditional reverse with a ten-year series of designs, one for each of the 50 states. Also in 1999, William Cousins was selected to add hair lines to Washington's portrait, greatly altering the coin's appearance. Washington Quarters were issued by the Philadelphia, Denver and San Francisco Mints.

Dates Composition Weight Diameter Edge 1932-1964 90% Silver 10% Copper 6.25 grams 24.3mm Reeded 1965-1998 Core 100% Copper Plating 75% Copper 25% Nickel Plating 5.67 grams 24.3mm Reeded 1975-1976 Limited Edition Silver-Clad Core 20.9% Silver 79.1% Copper Plating 80% Silver 20% Copper 5.75 grams 24.3mm Reeded
Interested in learning more about Washington Quarters? Red Book Washington & State Quarters - Q. David Bowers Washington Quarter Book 1932-1941 Volume 1 - Wiles Washington Quarter Book 1942-1944 Volume 2 - Wiles Washington Quarter Book 1945-1949 Volume 3 - Wiles