I found this walking on my best site and believe it to be agate
I think more and more after seeing the birds on this site
that this is a head of an agate bird effigy
probably that or an effigy of some type. The bird was a fairly common effigy item. I have only seen a few good whole Bird stones in collections. I would never consider buying an item like that as it is something that is faked and seen at many shows. Most are broke when found unless its a burial item. But that being said it is still a treasure of an artifact. Did you ever figure out your site or are have you hunted multiple sites?