Purbeck stone Purbeck stone Purbeck stone refers to building stone taken from a series of limestone beds found in the Upper Jurassic to Lower Cretaceous Purbeck Group, found on the Isle of Purbeck, Dorset in southern England. The best known variety of this stone is Purbeck Marble. The stone has been quarried since at least Roman times up to the present day. The Purbeck Group is a sequence of sedimentary rocks that were deposited in a shallow freshwater to brackish lagoonal setting. It ranges in age from Tithonian to Berriasian. Limestone beds are developed at various levels throughout the sequence, each with
Onondaga Limestone of Virginia. Relative age dating of the Onondaga places its formation in the Eifelian to Givetian stage of the Middle Devonian period, or 391.9 to 383.7 Ma. Radiometric dating of a sample from the bentonite at the top of the Onondaga placed it at 390 ± 0.5 Ma. The formation is time equivalent with the Floresta Formation of the Altiplano Cundiboyacense, Colombia. Onondaga limestone was quarried as dimension stone for construction of limestone buildings. The following buildings contain structural Onondaga limestone: Onondaga Limestone The Onondaga Limestone is a group of hard limestones and dolostones of Devonian age that form an