Minted in 1976 during the U.S. bicentennial, some quarters were struck without a mint mark due to an error, making them rare and valuable collector's items.
Despite efforts to use steel for pennies during WWII, a small number of copper pennies were minted in 1943, making them exceedingly rare and sought after.
A minting error in 1955 resulted in some Lincoln cents being struck with a double image, creating a distinctive doubling effect, highly prized by collectors.
Some Presidential Dollar coins were minted without the edge lettering indicating the coin's denomination and mint mark, due to a minting error, making them rare and valuable.
In 2000, General Mills included special "Cheerios" dollars in select cereal boxes to promote the Sacagawea dollar, featuring a distinct reverse design and highly collectible.
Uncovering a historic 1794 Flowing Hair Dollar at a garage sale, valued at hundreds of thousands of dollars, was a dream come true for one lucky shopper.
A minting error on some 2004 Wisconsin Quarters resulted in an extra leaf on the ear of corn in the design, making these coins rare and valuable.
A small number of 1971 Eisenhower dollars were minted without the mint mark ("S" for San Francisco) due to an error, making them extremely rare and sought after by collectors.