I found this with my Dad at Houghton Quarry in Dunstable today along with some shells and other things. It was in hard chalk (that was also limestoney). Is it a shark's tooth or a coprolite?
It is hard to tell, but I think it is a fossil crab or a fossil lobster. It also could also be a bone fragment, but I would say fossil crab. I hope an expert gives their opinion on this one because it is very interesting.
A very interesting find - well done, your specimen looks a lot better than the ones we find on the Holderness coast that are usually contained in pyritic cannonballs from the Lower Jurassic about 200myo.
You have had a couple of I,Ds on your specimen and was wondering if I had something similar, I have posted these images before but to me they are just plain old coprolites that I would like to learn more about.
Once again DotB well done! they are not a common fossil to find especially preserved like your specimen.