Winner of this auction gets all six of these seed fern slabs from the from the famous fern fossil site near St. Clair, Pennsylvania. Fossils from this site are unique in the world in that the fossil compressions are white to yellowish orange color instead of the usual dark colors at other fern fossil sites. The colors are entirely natural and unique to this site. The slabs feature multiple clear impressions of the form genera Alethopteris and Neuropteris, and Pecopteris. They are of Pennsylvanian age, approx. 310 million years old--far older than the oldest dinosaurs! The plants are of the type that compress into coal, which is mined nearby. See ruler in the photos for scale. Most of the slabs also have plant fossils on the reverse sides. I will include a sheet describing and illustrating various types of Pennsylvanian age plants. These would make wonderful additions to any fossil collection. Low starting bid and no reserve. Buyer to pay $3.85 shipping in the United States. Thank you.