This nut is possibly from a previously unknown and extinct plant species. The detail on this mystery item is exquisite. I believe it to be a replacement fossil; the organic replacement by minerals. It looks to be made of Jasper but that is just a guess at this point. There is a little damage on the "stem" as you can see. This fossil has not been cleaned or repaired yet, it's as is. Every expert that has looked at my photos thinks it's man made. They have not held it in their hands.

Approximate circumference of an averaged sized acorn.