Grinding stone or just river rock?

[Hoosier Digger]

I would like confirmation that I found a grinding stone. I will be heartbroken if it is just an oblong river rock. It was found in a farm field in central Indiana. Obviously, it has been knocked around and scarred considerably by farm equipment. Also, a slab had been fractured off the underside. The underside appears to be flat relative to the other sides. Thanks in advance for your help.

 

[CreekSide]

It could have been used as a Roller Pestle but being so banged up it’s just a guess. It has the correct shape as one. Use being just like a modern day rolling pin.

 

[antmike915]

No clue but I don't blame you for picking it up. Were other artifacts found in the same area?

 

[Hoosier Digger]

No clue but I don't blame you for picking it up. Were other artifacts found in the same area?

The owner has found a few points over time. I have found nothing!