Collectors especially want the 1969-S Doubled Die Lincoln Cent mistake coin.
Small and large date 1960 Lincoln Cents exist. Rare, especially with minting faults, is the little date variation. Depending on condition and variation, these coins can cost over $3,000.
As the last 90% silver U.S. half-dollar, the 1964 Kennedy Half Dollar is exceedingly precious today.
Some 1965 U.S. Mint quarters were accidentally manufactured with 90% silver planchets, even though the mint switched to cupronickel-clad coins. Rare and valuable mistake coins can sell for $7,000 or more.
Other unusual mint errors include the 1968 No-S Roosevelt Dime. Some San Francisco dimes from this year were erroneously manufactured without the “S” mintmark.