Macrocrinus Crinoid Fossil With Gastropod - Indiana

This is a cool association on a very detailed Macrocrinus mundulus crinoid with a Platyceras equilateralis gastropod "hiding" in it's arms. The quality of preparation on this fossil is exquisite - using skillful air-abrasion techniques under a stereo microscope. The crown of this specimen is 1.8" long on a 3.2x2.2" piece of limestone.]

The crinoid has been remounted to the limestone matrix.

It is believed that crinoids from the Ramp Creek Limestone were buried in sediment from nearby deltas during storms. The resulting siltstone deposits are soft enough that fossils can be extracted in exquisite, three-dimensional relief.