Kentish ragstone

Kentish ragstone is a hard grey limestone in Kent, England, drawn from the geological formation known as the Hythe Beds of the Lower Greensand. For centuries it has been quarried for use both locally and farther afield.

Ragstone occurs in a geological formation known in the Hythe Beds of the Lower Greensand, a layer of limestones running from Kent into Surrey which was laid down in the Cretaceous period. It outcrops in various places, notably at the cliffs of Hythe, Kent (whence it gets its name) and along the Greensand Ridge above the Weald of Kent. Ragstone occurs in bands between 15 cm and 60 cm thick, alternating with bands of a loose material called Hassock. These bands are of similar thickness and the difference in colour between them gives quarry faces a striped appearance. When the stone is extracted from the quarry, it appears to be of a grey green or blue grey colour but later weathers to an autumnal hue which, together with its hard-wearing properties, traditionally made it an attractive material for public building works.

With hard rock for building being in short supply in south-east England, it was inevitable that the only significant source of hard limestone – Kentish ragstone – would be used in building from an early period. Since Roman times, ragstone has been used in roughly squared blocks for building walls. The stone was almost certainly quarried at the Tovil quarry near Maidstone, and then transported by boat along the River Medway to London. A Roman ship discovered at Blackfriars had a cargo of Kentish ragstone, probably from Maidstone, on board. Examples of Roman uses include the Roman walled cemetery at Boughton and the old Roman wall near Tower Hill underground station. It is possible that ragstone quarrying contributed to the rise of a small town in the Maidstone area in Roman times. Two villas in the locality had links with the quarrying and a settlement could have grown up for those working in the quarrying and shipping industries, as well as for those engaged in providing services to them.

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