Unusual Rock in TN

[HelloitsB]

We found this rock around the Watauga Lake area of Eastern Tennessee (see pictures), and aren't sure what the mineral/rock inside might be that appears so black in most exposed places. Please let us know your thoughts.

 

[niffler]

Flint?

 

[sawmill man]

Yes it dos look like what we call a ball of flint. you actually have something some people haven't seen ,they see flint in worked forms and chips but have never seen it in its raw form

 

[P.ALLEN]

Definitely a weathered chert (flint) nodule, you can see the bulb of depression in the parts that are fractured.