These are beautiful, display piece featuring a pair of 2 1/2" wide Hoploscaphities nicolletii ammonites along with many small fossil clams and gastropods. They were collected from the Fox Hills Formation of South Dakota and have been wonderfully prepared from the hard concretion they were found in. The base of the rock has been cut flat, so that the specimen displays very aesthetically without the need for a display stand. Within the rock are small fossilized clams and ammonites shell fragments which allow you to find something new each time you look at it.
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.