I checked the local CoinStar machine today and saw several coins in the reject bin. Usually a foreign coin causes the machine to reject coins, buy all 30 of the coins were US pennies, probably from the same person but I can not be sure. One had been hammered to nearly the size of a quarter; that one probably caused the rejection. Of the others, 8 were zinc, 19 were Lincoln Memorial copper, and two were wheat pennies, a 1956 which had two wire-cutter marks, and this altered 1946-S penny: The coin was probably altered with a file to pass as a dime in a vending machine. It weighs 2.67gm, is 19mm in diameter, and the sides are smooth. I had heard of pennies altered this way but had not seen one until now. On December 3, 2010 President Obama pardoned a man for doing this "coin mutilation" in 1963, posted here: https://www.cointalk.com/threads/pres-obama-pardons-man-convicted-of-mutilation-of-coins.143584