Ammonite (Hoploscaphites) & Baculites Association - South Dakota

This is a wonderful association of the ammonite Hoploscaphities brevis and several baculites (straight cephalopods). They come from the Late Cretaceous Pierre shale of South Dakota. The piece has been wonderfully prepared and the ammonites all have iridescent shells. It would make for a great display sitting on shelf or desk.

These 70 million year old ammonites lived when South Dakota was a shallow inland sea. It was found preserved in a concretion that was split open. It then had to be hand prepared to remove the hard rock surrounding it from the shell, a very time consuming task.