|Here is a palm sized piece of a seed fern fossli plate of the species Alethopteris serli from the classical site of St Clair in Pennsylvania.|
The fossil leafs from the Llewellyn Formation show usually a attractive silver white preservation.
|St Clair, Schuylkill County, Pennsylvania, USA|
|Size of plate:||about 120 x 70 mm|
|Age:||Carboniferous (Pennsylvanian), Llewellyn Formation (about 320 Ma)|