A one-of-a-kind 1943 U.S. penny accidentally struck in copper rather than zinc was sold by a New Jersey dealer in 2010 for $1.7 million, with the proceeds given to charity.
The new owner is a Southwestern U.S. business executive who wishes to remain anonymous. The coin is the only known example of a 1943 penny incorrectly struck in a copper alloy. Zinc-coated steel was used for producing cents in 1943 to conserve copper for wartime uses. Only a small handful of coins were mistakenly struck on bronze planchets left over from 1942.
"We estimate that less than 20 Lincoln cents were erroneously struck in bronze at the Philadelphia and San Francisco mints in 1943, but this is the only known example from the Denver Mint," said Don Willis, president of Professional Coin Grading Service.
"This is the world's most valuable penny," said Laura Sperber, president of Legend Numismatics of Lincroft, N.J. "It's the only known example of a 1943-dated Lincoln cent incorrectly struck in a copper alloy at the Denver mint. Zinc-coated steel was being used for pennies in 1943 to conserve copper for other uses during World War II, and this one was mistakenly struck on a bronze coin disc leftover from 1942. It took four years of aggressive negotiations with the coin's owner until he agreed to sell it."