This is a nicely defined fossil cluster of the fern Macroneuropteris macrophylla preserved inside an ironstone nodule that has been split open. It comes from the famous Mazon Creek Lagerstätte. These ironstone nodules have been collected for decades from the spoil heaps of abandoned coal mines near Coal City, Illinois. The Mazon Creek fossil beds are a conservation lagerstätte (deposit with exceptional fossil preservation), located in Illinois. This location of late Paleozoic (~307 million years ago) biota, ranks among many of the other great fossil sites around the world. The large variety of fossils collected here, vary between plants and animals, including soft bodied and insect preservation. The fossils from this site are often quite detailed and are preserved within siderite (iron carbonate) nodules. Concretion size: 6 cm Macroneuropteris macrophylla Moscovian / Desmoinesian Francis Creek Shale Member, United States of America, Illinois, Mazon Creek Region Rare