A penny minted from the wrong metal in World War II has been sold for $1.7 million, said Laura Sperber of Legend Numismatics in Lincroft, who arranged the sale. Virtually all United States cents minted in 1943 were struck in steel rather than copper alloy, and are worth only a few cents each today, but a few coins were mistakenly made from bronze blanks left over in mint machinery. The coin was unknown to the collectors until 1979. Proceeds will go to charity.