I D please

I'd say nutting stone. Looks too big and grainy for a bow drill spindle cap. Either that or somebody shot it with a rifle. :)
Thread starter #4
The reason I picked it up was because it was an odd rock for the area. I just noticed the dip in the top this morning when I was getting it out of the tractor. I've seen what we call "grinding rocks", but this one just looks odd. It was in the middle of a field. Maybe somebody did shoot it.