fossilised nut?

[Jo Attwood]

Found this little fossil in chert/flint gravel, and heard a rattling. Upon breaking open, there was a smaller lighter coloured fossil inside, leading me to believe it is some sort of nut. 

It has what looks to be a scar at the bottom, possibly for attaching? it split neatly along the line into two parts.

[Jo Attwood]

about 2 cm, found in gravel in the back of a uk pub

[Fossildude19]

Welcome to the Forum.  

This looks like a weathered flint nodule with a sponge inside, perhaps?

 

Maybe @TqB can say more about it. 

Cropped, and brightened:

 

 

[TqB]

I agree with Tim. It's a sponge in flint, upper Cretaceous in age.

[Jo Attwood]

Thank you.  It looked very organic on the outside too.

 

[abyssunder]

I agree with the others. 

Nice find!

[Jo Attwood]

Thanks all of you.  I shall have to go back to my local pub garden to check for more now!