I've had this nickel in my possession for years now. I was ordering at a McDonalds one day and I bent over to look under the register for some loose change. I found the nickel pictured here and was surprised to see it. For the two years I've owned this, I had assumed it was a novelty nickel or one that was rigged to always land on heads. The pictures aren't necessarily the best but the obverse shows a standard nickel. It is 2001-P. The reverse, cut deep into the coin is a concentric "finger print" pattern. If this was an error, I can't tell how it could have occurred. Is this an error or just a novelty fake.
I believe what you have here is half of a magician's two headed coin. the insert that makes the other side has fallen out and you have what's left behind. Richard