The group of fossil shells covers Gastropods, Bivalves, Brachiopods and other molluscs. Both salt-water and fresh water shells, covering the very first shells to those of the Pleistocene.
A shell, is a hard, protective outer layer created by an animal that lives in the sea. These are the exoskeletons of invertebrates (animals without a backbones).
We also have a dedicated fossil website with more fossils to choose from.