My 7 year old son found this fossil whilst cracking open flint in Deal, Kent. The fossil (assuming it is) looks like scales/cells/shell and is chalky. The oblong lines are raised and well defined and tough to the touch. It certainly looks like a natural biological pattern. It looks very a little smaller than a golf ball stuck in the flint. Its edges disappear under the flint with the appearance that it is a sphere. Be glad if anyone has an idea. Thanks[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/ye4XU.jpg