what is it

[Navychief]

not sure if it is a tooth or not, any help would be appreciated. Looks like enamel on outside

[Al Dente]

It looks like a heavily mineralized bone fragment.

[Pliosaur]

Do you have a geographical location where it was found? Looks a bit like a weathered piece of rock to me, although need better close up pictures to be sure. 

[Advantage]

Do we see trabecular in the interior aspect, it does possibly look like bone or maybe a section of mammal antler. I have seen similar here in the UK from the North Norfolk coast. Just a very tentative  thought.

[Brandy Cole]

I agree that it looks like a fossil bone fragment.  The spongy material in the center in the last picture does look like trabecular bone tissue to me.

 

Unfortunately with a broken piece this size, I don't see enough detail to help narrow it down to species, and I'm unfamiliar with the geography of your area, so I can't suggest possible candidates.