Phosphate nodule has a lot of symmetry, is it a fossil? Found in Charleston SC.

[r00t2400]

One day I’ll learn to differentiate between phosphate nodules and fossils, today is not that day. Thanks for any input you have, this object appears to have symmetry on all sides, is it a fossil? I found it on the beach in South Carolina. 

[Plax]

Looks crabby to me but local experts will have a better idea what it is.

[Fossildude19]

I was thinking possibly the internal cast of a fish skull, but I would wait for some more local opinions. 

[Al Dente]

42 minutes ago, Fossildude19 said:

I was thinking possibly the internal cast of a fish skull, but I would wait for some more local opinions. 

It does look like a skull endocast. Maybe too big for fish. Mammal? Pretty neat find whatever it turns out to be.

[crabfossilsteve]

Boy, my first impression was crabby too, but would certainly defer to local experts.

[Al Dente]

Another possibility, it could be part of a fish skull. Here are a couple examples from the www.elasmo.com website.

 

 

[Plax]

I'm with Al on this one. I have to admit that I see crabs and sponges everywhere...