Name:   Fern Frond and Sphenophyllum Age:  Pennsylvanian Formation:  Llewellyn Formation Location:  Near St. Clair, Pennsylvania Size:  Plate is 6.8 inches across This is a very distinct plant fossil. It is a striking plate with a fern frond and a Sphenophyllum branch from Pennsylvania. This specimen is replaced with the mineral Pyrophyllite, which gives the fossils their stunning white color. The plants have great detail preserved and contrast beautifully with the black matrix plate.The fossils are almost perfectly spaced on the natural plate of shale. This is a collectible pair of fossil plants from the Coal Age of Pennsylvania.