Fossils in ironstone nodules I collected near my folks’ place on a strip-mine lake near the Mazon Creek in Grundy County near Morris, Illinois. This area is sometimes referred to as one of the Lagerstätten (i.e. mother lode) – one of few places on earth where conditions were just right to preserve a rich deposit of extremely well-preserved fossils. (Mine aren’t in the best shape, but a huge variety of detailed fossils have been found here, including soft-bodied animals such as the Tully monster.) More about the Mazon Creek area (Illinois State Museum). Even more (Wikipedia)
Of course, any assistance identifying these specimens would be greatly appreciated.