Wheal Vor
Encyclopedia
Wheal Vor was a metalliferous mine about two miles north west of Helston
Helston
Helston is a town and civil parish in Cornwall, England, United Kingdom. It is situated at the northern end of the Lizard Peninsula approximately 12 miles east of Penzance and nine miles southwest of Falmouth. Helston is the most southerly town in the UK and is around further south than...

 and one mile north of the village of Breage
Breage, Cornwall
Breage is a civil parish and village in Cornwall, England, United Kingdom. The village is situated three miles west of Helston....

 in the west of Cornwall
Cornwall
Cornwall is a unitary authority and ceremonial county of England, within the United Kingdom. It is bordered to the north and west by the Celtic Sea, to the south by the English Channel, and to the east by the county of Devon, over the River Tamar. Cornwall has a population of , and covers an area of...

, England, U.K. It is considered to be part of the Mount's Bay
Mount's Bay
Mount's Bay is a large, sweeping bay on the English Channel coast of Cornwall in the United Kingdom, stretching from the Lizard Point to Gwennap Head on the eastern side of the Land's End peninsula. Towards the middle of the bay is St Michael's Mount...

 mining district. Until the mid–19th century the mine was notable for its willingness to try out new innovations. Although very rich in copper and tin ores, the mine never lived up to its expectations, and during the later part of the 19th century had several periods of closure.

Geology

The country rock
Country rock (geology)
Country rock is a geological term meaning the rock native to an area. It is similar and in many cases interchangeable with the terms basement and wall rocks....

 at the mine is killas
Killas
Killas is a Cornish mining term for metamorphic rock strata of sedimentary origin which were altered by heat from the intruded granites in Devon and Cornwall, England. The term is used in both Devon and Cornwall.-Origin of killas:...

, mostly hard, blue-grey rock. The mine's main produce was copper and tin derived from the nearby Tregonning-Godolphin granite, part of the Cornubian batholith
Cornubian batholith
The Cornubian batholith refers to the group of associated granite intrusions which underlie the south-western peninsula of Great Britain. The main exposed masses of the batholith are seen at Dartmoor, Bodmin Moor, St Austell, Carnmenellis, Land's End and the Isles of Scilly. It formed during the...

. There were four main lode
Lode
In geology, a lode is a deposit of metalliferous ore that fills or is embedded in a fissure in a rock formation or a vein of ore that is deposited or embedded between layers of rock....

s at the mine, two of which were crossed by two wide elvan
Elvan
Elvan is a name used in Cornwall and Devon for the native varieties of quartz-porphyry. They are dispersed irregularly in the Upper Devonian series of rocks and some of them make very fine building stones...

 dykes
Dike (geology)
A dike or dyke in geology is a type of sheet intrusion referring to any geologic body that cuts discordantly across* planar wall rock structures, such as bedding or foliation...

, 20 foot wide. At the intersections the lodes widened and mineralization spread through the dykes, forming irregular masses which were stoped
Stoping (mining method)
Stoping is the removal of the wanted ore from an underground mine leaving behind an open space known as a stope. Stoping is used when the country rock is sufficiently strong not to cave into the stope, although in most cases artificial support is also provided...

 to the full width of the dykes.

Early history

Wheal Vor is an ancient mine: the ground shows the remains of old surface excavations
Open-pit mining
Open-pit mining or opencast mining refers to a method of extracting rock or minerals from the earth by their removal from an open pit or borrow....

 following the lodes, and mining may have taken place here in late Roman times. The underground mine probably started in the 15th century and continued until 1715, producing mainly copper ore. The mine was associated with the Godolphin family
Earl of Godolphin
Earl of Godolphin was a title in the Peerage of England. It was created in 1706 for Sidney Godolphin, 1st Baron Godolphin, the Lord High Treasurer. At the same time, he was created Viscount Rialton. In 1684 he had already been created Baron Godolphin, of Rialton, also in the Peerage of England...

 who were keen on trying out recent innovations, and through their connections it may have been the first mine in Cornwall to make use of gunpowder
Gunpowder
Gunpowder, also known since in the late 19th century as black powder, was the first chemical explosive and the only one known until the mid 1800s. It is a mixture of sulfur, charcoal, and potassium nitrate - with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer...

, at the close of the 17th century.

Shortly after 1700 the mine may have been one of the few sites to trial Thomas Savery
Thomas Savery
Thomas Savery was an English inventor, born at Shilstone, a manor house near Modbury, Devon, England.-Career:Savery became a military engineer, rising to the rank of Captain by 1702, and spent his free time performing experiments in mechanics...

's pump, which was, according to his patent application, "A new invention for raiseing of water … by the impellent force of fire, which will be of great use and advantage for drayning mines…". It is not certain whether Savery's experiments took place at Wheal Vor or at another nearby mine, but it is known that c. 1710 a Newcomen engine had been installed here, which was probably the first in Cornwall.

Other innovations that were trialled at the mine included the second Woolf
Arthur Woolf
Arthur Woolf was a Cornish engineer, most famous for inventing a high-pressure compound steam engine. As such he made an outstanding contribution to the development and perfection of the Cornish engine.Woolf left Cornwall in 1785 to work for Joseph Bramah's engineering works in London...

 engine in the county (1815); one of the first Brunton
William Brunton
William Brunton was a Scottish engineer and inventor.He was the eldest son of Robert Brunton of Dalkeith, where he was born...

 Calciners
Calcination
Calcination is a thermal treatment process applied to ores and other solid materials to bring about a thermal decomposition, phase transition, or removal of a volatile fraction. The calcination process normally takes place at temperatures below the melting point of the product materials...

 (1830); and an early man engine
Man engine
A man engine is a mechanism of reciprocating ladders and stationary platforms installed in mines to assist the miners’ journeys to and from the working levels...

 (c. 1856). It also one of the few mines to operate its own smelter
Smelting
Smelting is a form of extractive metallurgy; its main use is to produce a metal from its ore. This includes iron extraction from iron ore, and copper extraction and other base metals from their ores...

, having taken over the one owned by the Cornish Copper Company (a major shareholder) in 1823 and later moving to the mine.

The years between 1812 and 1848 were the mine's most successful, and it was for a time the richest mine in Cornwall. The ore raised from the 274 fathom (501 metres) level contained on average 5% tin, instead of the 1–1.5% that was usually found in Cornish mines, and for some time after the discovery of this rich lode the mine regularly produced 200 tons of white tin
White tin
White tin is refined, metallic tin. It contrasts with black tin, which is unrefined tin ore as extracted from the ground. The term "white tin" was historically associated with tin mining in Devon and Cornwall where it was smelted from black tin in blowing houses....

 per month. In 1840 the mine was employing 1,174 people, but it closed between 1848 and 1853.

1850 onwards

In 1854 a 100 inches (2.54 m) steam engine, the largest in Cornwall at the time, was installed on Crease's shaft
Shaft mining
Shaft mining or shaft sinking refers to the method of excavating a vertical or near-vertical tunnel from the top down, where there is initially no access to the bottom....

for draining the mine. This engine was built by Harvey & Co of Hayle
Hayle
Hayle is a small town, civil parish and cargo port in west Cornwall, United Kingdom. It is situated at the mouth of the Hayle River and is approximately seven miles northeast of Penzance...

 (the other main shareholder in the mine) and its starting was accompanied by a large celebration. But by 1860, it and another 85 inches (2.16 m) were using 600 tons of coal a month, which was determined to be unsustainable so both engines were stopped and later sold.

From a peak production of over 840 tons of black tin
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 has to be concentrated by a number of processes to reduce the amount of gangue it contains before it can be sold...

 in 1865 and 1866, the output from the mine declined until in 1877 only 13 tons was produced. The mine was then apparently idle until 1881, when five people were working there. From then until 1885 up to 22 people were employed, though only minimal amounts of ore were sold. There was another gap until 1906, when 65 people were recorded as working at the mine, 16 of them underground. The mine produced some black tin between 1907 and 1910, but then evidently closed again, probably due to difficulty keeping water out of the mine. In 1967 another attempt was made to reopen the mine, but it came to nothing.

Wheal Vor was the main component of the "Great Wheal Vor United" group of mines, which included among others, Polladras Mine, Penhale Wheal Vor, Wheal Metal and Sithney Wheal Metal. Wheal Vor also took over the mining sett
Mining sett
Mining setts were a legal arrangement used historically in the counties of Devon and Cornwall in South West England to manage the exploitation of land for the extraction of tin....

s of two other mines: Carleen Mine (otherwise known as West Wheal Vor), and Wheal Vreah.

Today, there is little visible above ground of the once extensive sett of the mine. An engine house and chimney are the most obvious remains.
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