I bought this nickel a while ago and just thought the mint mark had been filled with grease or worn away when it was struck. Then I recently got to reading about Henning Nickels and decided to inspect it a little more. It obviously hasn't turned the ugly color wartime nickels usually turn and it's missing the mint mark. It doesn't really look silver to me but wartime nickels did have a lower purity so it may well be. The "R" in "PLURIBUS" looks normal but that still doesn't eliminate it.
Could someone with higher experience in this field verify this possible counterfeit?