This is a small block of Inferior Oolite limestone with an ammonite and bivalve. The tiny ooliths are very clear; these formed from sand grains and shell fragments that were rolled around in a shallow warm sea, gathering layer upon layer to form the spherical oolith.
Horn Park Quarry near Beaminster is the smallest National Nature Reserve (NNR) in Britain, being just one acre or 0.32 hectares in size. It was once a working quarry but it is no longer and the remaining outcrop is protected by a fence. There is no collecting other than for scientific and educational purposes. A section of the fossil beds has been stripped back and protected from the weather by a removable cover. To arrange a visit, contact the Senior Reserve Manager on 07899 731404.
Find out more about ammonites on the molluscs pages.