5.1" Iridescent Hoploscaphites Ammonite Fossil - South Dakota

Iridescent Hoploscaphites Ammonite Fossil - South Dakota #270091

This is a bumpy, 5.1" wide Hoploscaphities ammonite specimen collected from the Pierre Shale of South Dakota. The ammonite is excellent condition, considering the difficulty (and time required) to remove it from the rock. The shell exhibits some orange and purple iridescence in spots when rotating it beneath a light source. The rock it was found in has been almost entirely removed with a section of rock remaining along what could be considered the back side of the ammonite.

Comes with an acrylic display stand.

Ammonites were predatory cephalopod mollusks that resembled squids with spiral shells. They are more closely related to living octopuses, though their shells resemble that of nautilus species. True ammonites appeared in the fossil record about 240 million years ago during the Triassic Period. The last lineages disappeared 65 million years ago at the end of the Cretaceous.

What an ammonite would have looked like while alive.

These 70 million year old ammonites lived when South Dakota was a shallow inland sea. They were found preserved in concretions when split open. They then had to be hand-prepared to remove the hard rock surrounding them from their shells, a very time consuming task.

More about ammonites