Agglomerate, Ercall quarry.

Agglomerate, Ercall quarry.

This specimen of rhyolitic agglomerate was collected fro Forest Glen Quarry car park, at the foot of the Wrekin in Shropshire. The rocks in the quarry are Uriconian and of debated age. possibly Precambrian or early Cambrian. The agglomerate specimen is typical of an exposure in the quarry. The fragments of volcanic rock are purply and reddish in colour, and indicate deposition in a pyroclastic flow.