Fossil, sponge, indet sponge, worn flint nodule cut and polished to reveal internal structure of this specimen , from Cretaceous

Fossil, sponge, indet sponge, worn flint nodule cut and polished to reveal internal structure of this specimen , from Cretaceous
Fossil, sponge, indet sponge, worn flint nodule cut and polished to reveal internal structure of this specimen , from Cretaceous