Shropshire Routes to Roots

4.Quarrying

Where is it?

Shropshire has been geologically fortunate when it comes to extractable minerals. In general, the mineral beds run from the youngest in the north and east to the oldest in the south and west. The ancient Pre-Cambrian and Ordovician rocks running south through the county provided vein minerals such as lead, zinc and barite, as well as hard road stone. The Carboniferous beds provided the limestone for smelting. The New Red Sandstone overlying the greater part of the north of the county was the source of much building material. Glacial deposits overlie much of the latter, but these beds are rich sources of sand and gravel.

Haughmond Quarry Larger image, in a new window [96kb] [Secret Shropshire]

There have been many types of quarrying (Opens in a new window) in Shropshire, some of which have been quite extensive. Many quarries have been merged into the landscape by the sensitive use of trees or earth screens, so it is often quite hard to spot where a quarry is situated.

What's up on the Clee Hills?

The process of quarrying and utilising the way a bed is orientated is perhaps illustrated by reference to one of the oldest quarries, and one that still operates today, namely Clee Hill quarry. Map of Clee Hill area  (Courtesy of Streetmap.co.uk - Opens in a new window)  

There were various companies operating on the Clee at the end of the 19th century, and all tended to use similar methods to extract the stone, known locally as 'Jew-stone.' This was a corruption of the Welsh, 'Dhu-Stone' referring to its black colour. It is a very fine grain, extremely hard volcanic stone (basalt) and is found in a bed about 900 feet wide and 240 feet thick.

Dhu Stone Quarry, Clee Hill Larger image, in a new window [36kb] [Reproduced with kind permission of Shropshire Newspapers]

How was it won from the ground?

Stone was extracted from quarries in the side of the hill by blasting using explosives packed at the bottom of a drill hole. The drill, known as a 'jumper,' was between three and seven feet (1-2 metres) long and about one inch in diameter (2.5 cm) while the hammer weighed around 28 lb (12.5 Kilo). One man would hold and turn the drill, while the other would strike it with the hammer. It would normally take them about two hours to drill a hole of the required depth. This hole, and others, would be packed with explosives; the quarry cleared and then blasting would take place. Blasting would often take place at the end of a shift, with the new shift coming in to clear the rock, drill new shot holes, and fire them at the end of their shift

The primitive method known as 'fire setting' was used to break up large blocks of stone where drilling new shot holes and firing would be too expensive. Fire setting involved building a timber fire against the rock, or on top of it, and the heat would crack the rock into smaller pieces. Often the fire would be dragged away and the face doused with cold water to encourage the splitting.

Cobbled Street, Hill's Lane, Shrewsbury Larger image, in a new window [204kb] [Secret Shropshire]

What are cobbles? Much of this rock was converted into stone 'setts' which were cubic pieces roughly 6 inches (15cm) on an edge, used for road making in many major towns and villages to make what were commonly known as 'cobbled streets.' The surface was extremely hard-wearing, but was very slippery when wet. This caused many an accident with the iron shod wheels of the carts and hooves of the horses. Even in more modern times the rubber tyres of motor vehicles gained little purchase, and consequently, cobbled streets were covered with tarmacadam to render them safer.

Why dig in Condover?

In contrast to the Clee Hill Quarry, which produces very hard roadstone, the vast Condover Quarry complex produces sand and gravel used by the construction industry. Map of Condover Quarry area  (Courtesy of Streetmap.co.uk - Opens in a new window)  These deposits were laid down after the last ice age and are some of the newest rocks in the county: roughly 14,000 years old. They are accumulations of rock fragments that have been freed from their softer parent rocks by either physical weathering, or the abrasion of glaciers which, is then subsequently worn and transported by water or wind to accumulate in layers. The quarrying techniques to extract the sand and gravel are very different from those employed on Clee Hill. Here it is almost as simple as digging sand at the seaside, but on a much larger scale.

As a county, Shropshire produces around 1 million tonnes of sand and gravel per annum, which satisfies approximately 85% of its requirements. The county has reserves of around 21.6 million tonnes

Panorama of the Condover Quarry complex operated by Hanson Aggregates Ltd. Larger image, in a new window [36kb] [Reproduced with kind permission of S.C.C. Planning Development Control]

How many mammoths were found at Condover?

It was here at Condover in 1986 that the fossil remains of the famous Shropshire Mammoths were found. The Ludlow Museum and Resource Centre (Opens in new window) is now home to these relics.

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