Carcharias sp.
Late Cretaceous
Trivieres Chalk
Obourg, Belgium
6mm tooth on 20mm chalk matrix

Odontaspididae, shark

See: Herman, J., 1977. Les sélaciens des terrains néocrétacés et paléocènes de Belgique et des contrées limitrophes. Eléments d’une biostratigraphie intercontinentale. Mémoires pour servir à l’explication des Cartes géologiques et minières de la Belgique, 1975 (paru 1977), 15: 401 pp.

In case you can’t read French, Carcharias is a genus of sand tiger shark that appeared in the Late Cretaceous and still lives today. Because the lingual face of the crown is still covered by matrix is not possible to identify it to species.

This tooth has nice color and comes from an oddball locality for fossils – a chalk deposit in Belgium.