Hoploscaphities Ammonite Double - South Dakota

This is a beautiful double Hoploscaphities comprimus specimen from the Fox Hills Formation of South Dakota. It's been wonderfully prepared from the hard concretion it was found in, and stands up on it's own. There is a section of opalescent shell preserved on one of the ammonites that displays wonderful hues of pinks and greens.

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.