american indian artifacts

I found this rock while metal detecting in western MA along the VT border today. Not really sure what it is...any ideas? And yes, this is dental floss (aka redneck jewelry), lol. Thanks.

Good morning !! I'm hoping to get some opinions on these items. I love all things flint (arrowheads, blades), but my favorites are the stone tools, implements, and problematic pieces. They are all from Northwest Arkansas. The issue with tools is that fine line between worked stone, and...