Halecombe
Encyclopedia
Halecombe, is a limestone
quarry
near Leigh-on-Mendip
on the Mendip Hills
, Somerset
, England
.
The quarry exhibits pale to dark grey well-bedded Carboniferous
Limestone, about 350-320 million years old, dipping steeply and consistently northwards and numerous “fist-sized” calcite
inclusions within the limestones both solid and hollow with internal calcite crystal
growth. There are abundant near-vertical fissures and joints in the limestone with varying amounts of calcite mineralization and tufa
growth around groundwater seepages. There are abundant shelly fossils and corals.
Quarrying activity was initiated at Halecombe at the time of the Second World War. It had been worked under private ownership until purchased by Hobbs in the 1960’s; subsequently worked by Wimpey Hobbs following their amalgamation in the early 1980’s and by Tarmac Ltd
from the early 1990’s. It is now owned by Anglo American
.
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
quarry
Quarry
A quarry is a type of open-pit mine from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone, construction aggregate, riprap, sand, and gravel. They are often collocated with concrete and asphalt plants due to the requirement...
near Leigh-on-Mendip
Leigh-on-Mendip
Leigh-on-Mendip or Leigh upon Mendip is a small village on the Mendip Hills in Somerset, England. It lies roughly equidistant from Frome, Radstock and Shepton Mallet at about from each town....
on the Mendip Hills
Mendip Hills
The Mendip Hills is a range of limestone hills to the south of Bristol and Bath in Somerset, England. Running east to west between Weston-super-Mare and Frome, the hills overlook the Somerset Levels to the south and the Avon Valley to the north...
, Somerset
Somerset
The ceremonial and non-metropolitan county of Somerset in South West England borders Bristol and Gloucestershire to the north, Wiltshire to the east, Dorset to the south-east, and Devon to the south-west. It is partly bounded to the north and west by the Bristol Channel and the estuary of the...
, England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
.
The quarry exhibits pale to dark grey well-bedded Carboniferous
Carboniferous
The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Mya , to the beginning of the Permian Period, about 299.0 ± 0.8 Mya . The name is derived from the Latin word for coal, carbo. Carboniferous means "coal-bearing"...
Limestone, about 350-320 million years old, dipping steeply and consistently northwards and numerous “fist-sized” calcite
Calcite
Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite. Aragonite will change to calcite at 380-470°C, and vaterite is even less stable.-Properties:...
inclusions within the limestones both solid and hollow with internal calcite crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...
growth. There are abundant near-vertical fissures and joints in the limestone with varying amounts of calcite mineralization and tufa
Tufa
Tufa is a variety of limestone, formed by the precipitation of carbonate minerals from ambient temperature water bodies. Geothermally heated hot-springs sometimes produce similar carbonate deposits known as travertine...
growth around groundwater seepages. There are abundant shelly fossils and corals.
Quarrying activity was initiated at Halecombe at the time of the Second World War. It had been worked under private ownership until purchased by Hobbs in the 1960’s; subsequently worked by Wimpey Hobbs following their amalgamation in the early 1980’s and by Tarmac Ltd
Tarmac (company)
Tarmac is a company that is based in Wolverhampton in the United Kingdom and operates internationally. The company produces aggregates and road-surfacing materials, including tarmacadam, from which the company's name is derived...
from the early 1990’s. It is now owned by Anglo American
Anglo American (mining)
Anglo American plc is a global mining company headquartered in London, United Kingdom. It is a major producer of diamonds, copper, nickel, iron ore and metallurgical and thermal coal and the world's largest producer of platinum, with around 40% of world output...
.
See also
- Quarries of the Mendip HillsQuarries of the Mendip HillsThe Mendip Hills are the most southerly Carboniferous Limestone Upland in Britain and are found in northern Somerset.They are composed of three major anticlinal structures, each with a core of older Devonian sandstone and Silurian volcanic rocks...