Collectible coins often include specific types such as commemorative issues, proofs, and uncirculated coins. The United States 25-cent quarter, commonly known as the Washington Quarter, features the portrait of George Washington and was first minted in 1932. In 1971, the San Francisco Mint produced proof and uncirculated versions of the Washington Quarter, which are highly sought after by collectors due to their quality and finish. Mint marks on these coins can denote their place of production, with the "S" indicating the San Francisco Mint.

Item Denomination Series Year Mint
1971-S (San Francisco) Washington Quarters 25¢ (Twenty Five Cents, Quarter) Washington Quarters 1971 San Francisco