Coinsandcanada.com

Hi. I have a strange penny and I've done some searching and have found nothing about it, so I was wondering if anyone here might be able to give me an idea what I've got.

It's a 1981 Canadian 1 cent piece, which is very thin. The imprints on both sides are light, but detailed, so it really can't be this thin due to wear. The raised rim appears to be missing, making the coin very slightly smaller diameter than a normal penny.

The pictures below show both sides, and an edge on view with a normal penny for comparison.

Any ideas?

Acid, or something approaching acid, like Coke, fruit juices, etc.

Thanks. Now that I know what to search for, there's lots of info about this out there.

Thanks again.