Sheppey is one of the best locations for fossil collecting from the London Clay. The deposit is from the Eocene epoch, Ypresian stage and is around 52-51 million years old. The whole stretch of coast from Warden point to Sheerness is London Clay, but this section only deals with the location and finds around Warden Point.
Fossils to be found here include:
shark teeth
gastropods
bivalves
brachiopods
fish remains
turtles
lobsters
crabs
pyritised wood
seeds and fruit
ray teeth
worm tubes
nautili
coral
References:
A Field Guide to the London Clay of Sheppey, Kent