Blue John Cavern
Encyclopedia
The Blue John Cavern is one of the four show cave
s in Castleton, Derbyshire
, England
. The cavern, which takes its name from the semi-precious mineral "Blue John" or "Derbyshire Spar", is still mined for the mineral outside of the tourist season. The small amounts taken are turned into locally-made jewellery
. The miners who work the remaining seams are also the guides for underground public tours. The eight working seams are known as Twelve Vein, Old Dining Room, Bull Beef, New Dining Room, Five Vein, Organ Room, New Cavern and Landscape.
The cavern was featured on the 2005 TV programme Seven Natural Wonders
as one of the wonders of the Midlands.
bleu-jaune, meaning 'blue-yellow'. Large quantities of Blue John was sent to France
in the late 18th century where it was used for gilding by French Ormolu
workers during the reign of the Louis XVI (1774 – 1791). However, the French craftsmen were emulating ormolu ornaments already created by Matthew Boulton
of Birmingham
, who around 1765 was already calling the stone 'Blew John'.
An alternative origin of the name was suggested by John Royse, the lessee of the cavern in 1938. He noted that as an old miners' name for metal-blended stone was "Black Jack", Royse postulated whether the unique blue stone mined in these caverns led it to be known as "Blue John".
. Although blue fluorite occurs widely throughout Derbyshire, especially around Ashover
and Crich
, only the blue-purple and white-yellow variety is found in Castleton at Blue John Cavern and at the nearby Treak Cliff Cavern
.
Within the UK, blue fluorspars are also found in County Durham
(especially Weardale
), Cornwall
and Wales
. Other deposits of banded blue fluorite occur in Nevada
, United States, and Southern Iran
. Two cups found among Roman grave-goods near the Turkish/Syrian border, on the former Persian-Roman trade route, were made from Iranian blue-yellow banded fluorspar. Two Blue John vases have also been found during excavations at Pompeii
.
s of Blue John, these could be mounted with ormolu
as chimneypiece
garnitures. The earliest dated decorative application of Blue John in Britain are the marble fireplace panels, designed by neoclassical architect and interior designer Robert Adam
, that were installed at Kedleston Hall
near Derby
in 1762. Blue John became such a popular medium for ornamental bases, manufacturer and industrialist Matthew Boulton tried unsuccessfully to obtain exclusive mineral rights for the whole output from the Castleton mines.
Despite small-scale mineral extraction continuing at the Castleton caverns, similar blue and white-yellow banded fluorite is now imported into the UK from China
.
Show cave
Show caves — also called tourist caves, public caves, and in the United States, commercial caves — are caves that are managed by a government or commercial organization and made accessible to the general public, usually for an entrance fee...
s in Castleton, Derbyshire
Derbyshire
Derbyshire is a county in the East Midlands of England. A substantial portion of the Peak District National Park lies within Derbyshire. The northern part of Derbyshire overlaps with the Pennines, a famous chain of hills and mountains. The county contains within its boundary of approx...
, 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 cavern, which takes its name from the semi-precious mineral "Blue John" or "Derbyshire Spar", is still mined for the mineral outside of the tourist season. The small amounts taken are turned into locally-made jewellery
Jewellery
Jewellery or jewelry is a form of personal adornment, such as brooches, rings, necklaces, earrings, and bracelets.With some exceptions, such as medical alert bracelets or military dog tags, jewellery normally differs from other items of personal adornment in that it has no other purpose than to...
. The miners who work the remaining seams are also the guides for underground public tours. The eight working seams are known as Twelve Vein, Old Dining Room, Bull Beef, New Dining Room, Five Vein, Organ Room, New Cavern and Landscape.
The cavern was featured on the 2005 TV programme Seven Natural Wonders
Seven Natural Wonders
Seven Natural Wonders was a television series that was broadcast on BBC Two from 3 May to 20 June 2005. The programme took an area of England each week and, from votes by the people living in that area, showed the 'seven natural wonders' of that area in a programme.The programmes were:The series...
as one of the wonders of the Midlands.
Etymology
The commonest theory for the name Blue John derives from the FrenchFrench language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...
bleu-jaune, meaning 'blue-yellow'. Large quantities of Blue John was sent to France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
in the late 18th century where it was used for gilding by French Ormolu
Ormolu
Ormolu is an 18th-century English term for applying finely ground, high-karat gold in a mercury amalgam to an object of bronze. The mercury is driven off in a kiln...
workers during the reign of the Louis XVI (1774 – 1791). However, the French craftsmen were emulating ormolu ornaments already created by Matthew Boulton
Matthew Boulton
Matthew Boulton, FRS was an English manufacturer and business partner of Scottish engineer James Watt. In the final quarter of the 18th century the partnership installed hundreds of Boulton & Watt steam engines, which were a great advance on the state of the art, making possible the...
of Birmingham
Birmingham
Birmingham is a city and metropolitan borough in the West Midlands of England. It is the most populous British city outside the capital London, with a population of 1,036,900 , and lies at the heart of the West Midlands conurbation, the second most populous urban area in the United Kingdom with a...
, who around 1765 was already calling the stone 'Blew John'.
An alternative origin of the name was suggested by John Royse, the lessee of the cavern in 1938. He noted that as an old miners' name for metal-blended stone was "Black Jack", Royse postulated whether the unique blue stone mined in these caverns led it to be known as "Blue John".
Geology
Blue John is a type of banded fluoriteFluorite
Fluorite is a halide mineral composed of calcium fluoride, CaF2. It is an isometric mineral with a cubic habit, though octahedral and more complex isometric forms are not uncommon...
. Although blue fluorite occurs widely throughout Derbyshire, especially around Ashover
Ashover
Ashover is a village in the English county of Derbyshire. It is in the North East Derbyshire district of the county. It sits in a picturesque valley, not far from the town of Matlock and the Peak District national park. The centre of the village is a conservation area. The River Amber flows through...
and Crich
Crich
Crich is a village in Derbyshire in England. It has the National Tramway Museum inside the Crich Tramway Village, and at the summit of Crich Hill above, a Memorial Tower for those of the Sherwood Foresters regiment who died in battle, particularly in World War I.Built in 1923 on the site of an...
, only the blue-purple and white-yellow variety is found in Castleton at Blue John Cavern and at the nearby Treak Cliff Cavern
Treak Cliff Cavern
Treak Cliff Cavern is a show cave near Castleton in Derbyshire. It is part of the Castleton Site of Special Scientific Interest and by agreement with English Nature all the Blue John stone deposits on the visitor route are preserved. However, Blue John is regularly mined from areas not seen by...
.
Within the UK, blue fluorspars are also found in County Durham
County Durham
County Durham is a ceremonial county and unitary district in north east England. The county town is Durham. The largest settlement in the ceremonial county is the town of Darlington...
(especially Weardale
Weardale
Weardale is a dale, or valley, of the east side of the Pennines in County Durham, in England. Large parts of Weardale fall within the North Pennines Area of Outstanding Natural Beauty - the second largest AONB in England and Wales. The upper valley is surrounded by high fells and heather grouse...
), 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...
and Wales
Wales
Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...
. Other deposits of banded blue fluorite occur in Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
, United States, and Southern Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
. Two cups found among Roman grave-goods near the Turkish/Syrian border, on the former Persian-Roman trade route, were made from Iranian blue-yellow banded fluorspar. Two Blue John vases have also been found during excavations at Pompeii
Pompeii
The city of Pompeii is a partially buried Roman town-city near modern Naples in the Italian region of Campania, in the territory of the comune of Pompei. Along with Herculaneum, Pompeii was destroyed and completely buried during a long catastrophic eruption of the volcano Mount Vesuvius spanning...
.
Usage
In the 18th century a small local industry began turning vaseVase
The vase is an open container, often used to hold cut flowers. It can be made from a number of materials including ceramics and glass. The vase is often decorated and thus used to extend the beauty of its contents....
s of Blue John, these could be mounted with ormolu
Ormolu
Ormolu is an 18th-century English term for applying finely ground, high-karat gold in a mercury amalgam to an object of bronze. The mercury is driven off in a kiln...
as chimneypiece
Fireplace mantel
Fireplace mantel or mantelpiece, also known as a chimneypiece, originated in medieval times as a hood that projected over a grate to catch the smoke. The term has evolved to include the decorative framework around the fireplace, and can include elaborate designs extending to the ceiling...
garnitures. The earliest dated decorative application of Blue John in Britain are the marble fireplace panels, designed by neoclassical architect and interior designer Robert Adam
Robert Adam
Robert Adam was a Scottish neoclassical architect, interior designer and furniture designer. He was the son of William Adam , Scotland's foremost architect of the time, and trained under him...
, that were installed at Kedleston Hall
Kedleston Hall
Kedleston Hall is an English country house in Kedleston, Derbyshire, approximately four miles north-west of Derby, and is the seat of the Curzon family whose name originates in Notre-Dame-de-Courson in Normandy...
near Derby
Derby
Derby , is a city and unitary authority in the East Midlands region of England. It lies upon the banks of the River Derwent and is located in the south of the ceremonial county of Derbyshire. In the 2001 census, the population of the city was 233,700, whilst that of the Derby Urban Area was 229,407...
in 1762. Blue John became such a popular medium for ornamental bases, manufacturer and industrialist Matthew Boulton tried unsuccessfully to obtain exclusive mineral rights for the whole output from the Castleton mines.
Despite small-scale mineral extraction continuing at the Castleton caverns, similar blue and white-yellow banded fluorite is now imported into the UK from China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
.