Wheal Gorland was a metalliferous mine located just to the north-east of the village of

St Day St Day ( kw, Sen Day) is a civil parish and village in Cornwall, England, United Kingdom. It is situated between the village of Chacewater and the town of Redruth. The electoral ward St Day and Lanner had a population at the 2011 census of 4,473 ...

Cornwall Cornwall (; kw, Kernow ) is a historic county and ceremonial county in South West England. It is recognised as one of the Celtic nations, and is the homeland of the Cornish people. Cornwall is bordered to the north and west by the Atlantic ...

, in England, United Kingdom. It was one of the most important Cornish mines of the late 18th and early 19th centuries, both for the quantity of ore it produced and for the wide variety of uncommon secondary copper minerals found there as a result of supergene enrichment. It is the type locality for the minerals chenevixite,

clinoclase Clinoclase is a hydrous copper arsenate mineral, Cu3AsO4(OH)3. Clinoclase is a rare secondary copper mineral and forms acicular crystals in the fractured weathered zone above copper sulfide deposits. It occurs in vitreous, translucent dark blue to ...

cornwallite Cornwallite is an uncommon copper arsenate mineral with formula Cu5(AsO4)2(OH)4. It forms a series with the phosphate pseudomalachite and is a dimorph of the triclinic cornubite. It is a green monoclinic mineral which forms as radial to fibrous ...

kernowite Kernowite is a mineral which was first described in 2020. It is named for Cornwall, which in the Cornish language is ''Kernow''. Description Kernowite is a complex arsenate mineral with the composition . It was first described in 2020, and is c ...

and

liroconite Liroconite is a complex mineral: Hydrated copper aluminium arsenate hydroxide, with the formula Cu2 Al As O4�4(H2O). It is a vitreous monoclinic mineral, colored bright blue to green, often associated with malachite, azurite, olivenite, and cli ...

History

The production of the mine was very inconsistent because of the sporadic distribution of its rich ore-bodies: in 1833 George Abbot wrote that it had made profits of over £300,000, produced 1,400 tons of ore per annum, and ranked third, in terms of profits, just behind

Dolcoath mine Dolcoath mine ( kw, Bal Dorkoth) was a copper and tin mine in Camborne, Cornwall, England, United Kingdom. Its name derives from the Cornish for 'Old Ground', and it was also affectionately known as ''The Queen of Cornish Mines''. The site is ...

and

Consolidated Mines Consolidated Mines, also known as Great Consolidated mine, but most commonly called Consols or Great Consols was a metalliferous mine about a mile ESE of the village of St Day, Cornwall, England. Mainly active during the first half of the 19th ...

. However, in 1865 Thomas Spargo wrote "now part of St. Day United; idle". In the early 1790s Wheal Gorland was connected to the

Great County Adit The Great County Adit, sometimes called the County Adit, or the Great Adit was a system of interconnected adits that helped drain water from the tin and copper mines in the Gwennap area of Cornwall, in the United Kingdom. Construction started in 1 ...

and its own existing shallow adits were adapted to drain into this deeper adit. Records show that between 1815 and 1851 the mine produced 40,750 tons of 7½% copper ore, 15 tons of

black tin Black tin is the raw ore of tin, usually cassiterite, as sold by a tin mine to a smelting company. After mining, the ore must be concentrated by several processes to reduce the amount of gangue it contains before it can be sold. It contrasts ...

, and 18 tons of

arsenic Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, ...

. Much fluorspar was also produced, and gold was reputedly found in the

gossan Gossan (eiserner hut or eisenhut) is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein. In the ''classic'' gossan or iron cap all that remains is iron oxides and quartz, often ...

. In 1852 the mine was taken over by the St. Day United Group of mines and it became the main site for maintenance of the Great County Adit, but by 1864 it had been abandoned. The mine was reopened in 1906 when

Edgar Allen and Company Edgar Allen and Company was a steel maker and engineer, which from the late 19th century was based at Imperial Steel Works, Tinsley, Sheffield, South Yorkshire. The site was bounded by Sheffield Road, Vulcan Road and the Sheffield District Railway ...

reworked the stopes and the dumps for tin and tungsten ores. It sold 164 tons of tungsten ore and 18 tons of black tin before closing, for the last time, in 1909. Since 1988 the site has been designated as a Site of Special Scientific Interest because of the variety and quality of lead and copper minerals that have been found in the mine dumps. A condition summary compiled on 21 July 2010 reported that the site was in an ″unfavourable declining condition″ because growth of scrubland vegetation was encroaching on to the waste dumps and hindering future excavations in search of minerals for scientific study. The summary further states that the vegetation on the remaining mine dump may also be affecting the minerals themselves, as formation of new soil horizons could affect chemical processes within the dump.

References

{{SSSIs Cornwall geological, state=collapsed Tin mines in Cornwall Copper mines in Cornwall Sites of Special Scientific Interest in Cornwall Sites of Special Scientific Interest notified in 1988 Industrial archaeological sites in Cornwall

History

See also

References