Location: Missouri
Time period: Pennsylvanian
Formation: Muncie Creek Shale
At first i wanted to say some sort of skull material but I am unsure as I do not see many visible bony structures and I am inexperienced in such fields
Here are the image links in larger file sizes and if you are on pc you can zoom into them and see hopefully better detail
https://postimg.cc/GTvr5dD6
https://postimg.cc/sMTz8nBf
https://postimg.cc/cK6WNQYR