![Bell pits - geograph](https://upload.wikimedia.org/wikipedia/commons/1/12/Bell_pits_-_geograph.org.uk_-_413404.jpg)
A bell pit is a primitive method of
mining
Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic via ...
coal
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen.
Coal is formed when dea ...
,
iron ore
Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, or deep purple to rusty red. The iron is usually found in the fo ...
, or other minerals lying near the surface.
Operation
A shaft is sunk to reach the mineral which is excavated by miners, transported to the surface by a winch, and removed by means of a bucket, much like a well.
The bottom of the shaft is enlarged and a sloping roof is created as the desired mineral and surrounding rock is removed – giving its name because the pit in cross section resembles a
bell
A bell is a directly struck idiophone percussion instrument. Most bells have the shape of a hollow cup that when struck vibrates in a single strong strike tone, with its sides forming an efficient resonator. The strike may be made by an inter ...
.
Typically, no supports were used, and mining continued outwards until the cavity became too dangerous or collapsed at which point another mine was started, often in close proximity.
[ Example and illustrated description] This type of mine was in use in prehistoric times, the Middle Ages,
and a few continued in use until the early 20th century in the region around
Ford, Northumberland
Ford is a small village and civil parish in Northumberland, England, about from Berwick-upon-Tweed. The parish also includes Etal.
History before 1513
Very little is known of the history of the area before the Norman Conquest in the 11th cen ...
. Such pits are common at prehistoric flint working sites such as
Grime's Graves
Grime's Graves is a large Neolithic flint mining complex in Norfolk, England. It lies north east from Brandon, Suffolk in the East of England. It was worked between 2600 and 2300 BC, although production may have continued well into ...
in
Norfolk
Norfolk () is a ceremonial and non-metropolitan county in East Anglia in England. It borders Lincolnshire to the north-west, Cambridgeshire to the west and south-west, and Suffolk to the south. Its northern and eastern boundaries are the No ...
and also in the coal mining areas of Yorkshire, the
Forest of Dean
The Forest of Dean is a geographical, historical and cultural region in the western part of the county of Gloucestershire, England. It forms a roughly triangular plateau bounded by the River Wye to the west and northwest, Herefordshire to the n ...
,
and Leicestershire.
Bell pits often flooded due to a lack of a drainage system. This, together with the lack of support and the likelihood of collapse, meant they had a limited lifespan. The remains of bell pits can be identified by depressions left when they collapsed. In some places, they will follow a straight line as the seam of mineral is being followed. Bell pits were not an efficient way of extracting minerals as they only partially exploited the resources.
See also
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Drift mining
Drift mining is either the mining of an ore deposit by underground methods, or the working of coal seams accessed by adits driven into the surface outcrop of the coal bed. A drift mine is an underground mine in which the entry or access is above ...
*
Open-pit mining
Open-pit mining, also known as open-cast or open-cut mining and in larger contexts mega-mining, is a surface mining technique of extracting rock or minerals from the earth from an open-air pit, sometimes known as a borrow.
This form of mining ...
*
Industry and the Eglinton Castle estate
The Eglinton Castle estate was situated at Irvine, on the outskirts of Kilwinning, North Ayrshire, Scotland (map reference NS 3227 42200) in the former district of Cunninghame. Eglinton Castle, was once home to the Montgomeries, Earls of Eglin ...
*
Glossary of coal mining terminology
This is a partial glossary of coal mining terminology commonly used in the coalfields of the United Kingdom. Some words were in use throughout the coalfields, some are historic and some are local to the different British coalfields.
A
Adit
:An ...
References
Coal mining
Underground mining
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