Derfel Limestone
Stratigraphic range: Ordovician
Type	Formation
Lithology
Primary	Limestone
Location
Region	Wales
Country	United Kingdom

The Derfel Limestone is a geologic formation in Wales. It preserves fossils dating back to the Ordovician period.

• List of fossiliferous stratigraphic units in Wales

• Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to the Paleobiology Database". Retrieved 17 December 2021.