Possible Artifact – Anyone know what it is?

My father is a collector of Native American artifacts and has a large collection of arrow-heads and other things. He has found this last week and is wondering if anyone has any ideas of what it is or what it would have been used for. Also if you have any ideas where he can research this. Any ideas appreciated. Thanks

It is made of stone. I tried taking many photos and I had a hard time getting a good pic, but thanks for your interest!!