Three Jurassic Brittle Stars (Palaeocoma) - Lyme Regis

This is a trio of rare fossil brittle stars (Palaeocoma egertoni) from the Lyme Regis region on England. They are Lower Jurassic in age or approximately 190 million years old. The largest of the three specimen on the rock is 4.1" wide and the smallest is 1.1" wide. They have been prepared with air abrasives to reveal all of the beautifully preserved detail.

The black "staining" on the rock near the center of one of the brittle stars is pyrite. Often times these brittlestars have stable pyrite over the top of them, particularly on the central disk which spreads into the surrounding rock. This has to be ground away during preparation of the fossil. The grey spots on the rock near the central disk is remaining pyrite formations underneath the brittle star.