Two sides Ancient Museum Quality Carboniferous Fern Fossil Saint Clair Mine #1

All plant fossils were found in the Llewellyn Formation (300 mya, Pennsylvanian Period) and are one of the few places where one can find these very detailed white (sometimes yellow) ferns on a striking contrast of black shale. The plants died and fell into the swamp, where in a low temperature, pressure, and oxygen environment the plant tissue were slowly replaced by pyrite (from sulphides). Pyrophyllite (aluminum silicate, a whitish mineral) is believed to have replaced the pyrite at a later stage as the sediments piled up and the temperature and pressure became greater. The ferns most commonly found are Alethopteris, Neuropteris, Pecopteris, and Sphenophyllum.
Size: 5 3/4 inches in length x 4 1/4 inches in width
147.2 grams
This site is no longer open for excavation and those available are truly priceless. This specimen will come with a black stand. These have not been sprayed with any coating.