More fossils from Pennsylvania. These trilobite fragments are quite nice. We have places east of Louisville that will yield Cryptolithus pieces but they tend just be the lace collar and genal spines and are black/dark gray. The following fossils have the glabella and the lace collar and are orange (iron?). The cephalon sizes range from 5-15 mm.
These Cryptolithus sp. were found in Lebanon County, Pennsylvania in the Martinsburg formation.
Update: The yellow-brown color is limonite (hydrated iron oxide-hydroxide).