The circular structures on this sigillaria specimen are traces of vascular bundles (veins) that serve the leaves. The surface of this specimen has been eroded (decorticated) which results in these structures (parichnos_) appearing abnormally large. Sigillaria specimens of this type are assigned to the form genus syringodendron.
A 1/16-inch layer of coal covers much of the outside of this specimen.
Rock Type: Sandy shale
Interval: Coalburg seam
Age: Middle Pennsylvanian Period, approx. 307 million years.
Location: Nicholas County, West Virginia; Ramp Run Surface Mine #1, located about 12 miles north of Summersville, West Virginia. Turn west off route 19 north of Summersville onto Spruce Run Road. Follow it about 7 miles.