Here is a tooth my colleague found a lot of years near Cognac (Charente, France). It is from a sedimentary facies Purbeckian (Late Jurassic, Lower Cretaceous). The quarry was in the marl, we found many reptiles, teeth and fish scales there, and of very small shark teeth.
The size is 4 cm (1" 3/5)
Thanks for your help.
Coco