Hello!
This is something really stange I found a few time ago which had a really strange structure which I couldn't explain as a sedimentary one. I've always had it as a simple pseudofossil, but a few days ago I found another exact structure, although a little bit more fragmentary.
They are quite unusual, al least for me. What is clear to me is that in case they are fossils, they are fragments of bone. On one side they show a lineal pattern of holes, not really deep, where I think teeth were placed. One the other side they show a really characteristic pattern of triangle like holes, which I have supposed to be a really strong anchor point for muscles.
I think they could be fragments of pterygoid bones from some kind of snakes, because it's the only way these two pieces make any sense to me.
The patterns of the structures of both pieces are exactly the same, but I'm afraid my camera's depth perception is not good enogh in order to show that...
Measurements in mm.