After a recent tour of the U.S. Mint in Philadelphia, it was discovered that the minting process had changed to some degree. One of the changes was that "feeder fingers" were used during the striking of all denominations of U.S. coins. Prior to this tour, U.S. coins that were struck on feeder finger tips were authenticated and described as being struck on aluminum scrap. Coins from all modern denominations have been discovered that were struck on the tips of these feeder fingers.