Sphenophyllum are a type of foliage commonly found in environments that supported stands of calamites and other ancient plants that grew along river banks during the Carboniferous Period. This specimen was found in in shale layers overlying a sandstone bed which contained this specimen of a calamite stem.

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Rock Type: Shale
Formation: Kanawha
Interval: Coalburg seam
Age: Middle Pennsylvanian Period, approx. 307 million years.

Location: Nicholas County, West Virginia; Alex Energy. Inc., Robinson North Surface Mine, located about 10 miles west of Summersville, West Virginia, just north of Route 39. It is an active surface mine and requires permission for access.