I had to go take a picture for y'all. I have a strong suspicion that this was used by Native people a long while ago as a pounding tool. It was in my yard. There are at least two other rocks that are very similar that I find off and on in the yard.
I joke that when all fails, "Rock" is my tool of last resort. I have used it a few times.
PPOT. Meet my favorite tool:
