This Specimen has been sold.
1.7" Ordovician, Nautiloid (Plectoceras) Fossil - Wisconsin
This is a 1.7" wide example of a Middle Ordovician fossil Nautiloid (Plectoceras robertsoni) from Wisconsin. This fossil is part of an old collection from the Grand Detour Formation in Rock County. It's quite unusual to find examples this nice of the species.