Age: Uncertain (Permian-Carboniferous)
There is a dyke-like intrusion at Lowe’s Hill Quarry near Bartestree. Radiometric dating gives ages of 260 and 286 million years. The dyke has been intruded in three phases; green dolerite without olivine; darker and coarser-grained teschenite (olivine-analcime bearing dolerite); and basalt which forms the central and major part of the intrusion.
Most of this dyke has now been quarried away.
Bartestree Quarry, Herefordshire