Dime Arrows

Why would Native Americans have made holes in stones?
My parents’ house sits on farmland that used to be inhabited by Native Americans long ago. On the property, they’ve found arrow heads and a few large stones that have holes bored in them. There is a large, round stone that has a perfect hole the size of a dime in the center of it. The hole is only maybe a half inch deep. There is also a triangular shaped rock (looks like a big slice of pie) with two quarter shaped holes. They believe the stones belonged to Indians, but I’m curious as to what use they would have for these stones. Is it a type of artform, or maybe the stones were part of some sort of instrument? Does anyone know what they are and how old they are?
Watch who you’re calling paleface. I have some Native American blood in me, though it is aways back. Many if not most people who live in this area have some NA blood.
Shoot me some pics of it if you can. Mr.Twocrows@yahoo.com
It sounds like tools for shafting arrows. if the hole goes straight through it’s most likely for straightening the shaft.
I’d have to see it to be sure.
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