This is a beautiful, 2.3" wide, Ordovician aged starfish of the genus Petraster. It comes from the Kataoua Formation near Blekus, Morocco. The specimen shows an amazing amount of detail and the natural, orange coloration is due to the oxidization of iron pyrite. It's nicely centered on a thick piece of limestone, along with several edrioasteroids (Spinadiscus).
Both the positive and negative impression of this fossil is included.