100-527: Elvan is a name used in Cornwall and Devon for the native varieties of quartz-porphyry . They are dispersed irregularly in the Devonian series of rocks and some of them make very fine building stones (e.g. Pentewan stone , Polyphant stone and Catacleuse stone ). Greenstone is another name for this stone and it is often used for parts of buildings such as doorways so they can be finely carved. Most of
200-591: A folk music tradition that has survived into the present and is well known for its unusual folk survivals such as Mummers Plays , the Furry Dance in Helston played by the famous Helston Town Band , and Obby Oss in Padstow . Newlyn is home to a food and music festival that hosts live music, cooking demonstrations, and displays of locally caught fish. Cornubian batholith The Cornubian batholith
300-535: A cross argent'). According to legend Saint Piran adopted these colours from seeing the white tin in the black coals and ashes during his discovery of tin. The Cornish flag is an exact reverse of the former Breton black cross national flag and is known by the same name " Kroaz Du ". Since the 19th century, Cornwall, with its unspoilt maritime scenery and strong light, has sustained a vibrant visual art scene of international renown. Artistic activity within Cornwall
400-525: A first language in the late 18th century. In the 20th and 21st centuries, it has been revived by a small number of speakers. It is closely related to the other Brythonic languages ( Breton and Welsh ), and less so to the Goidelic languages . Cornish has no legal status in the UK. There has been a revival of the language by academics and optimistic enthusiasts since the mid-19th century that gained momentum from
500-759: A large part of the Cornwall National Landscape . The national landscape also includes Bodmin Moor , an upland outcrop of the Cornubian batholith granite formation. The county contains many short rivers; the longest is the Tamar , which forms the border with Devon. Cornwall had a minor Roman presence, and later formed part of the Brittonic kingdom of Dumnonia . From the 7th century, the Britons in
600-668: A large urban centre in south west Devon, is an important location for services such as hospitals, department stores, road and rail transport, and cultural venues, particularly for people living in east Cornwall. Cardiff and Swansea , across the Bristol Channel, have at some times in the past been connected to Cornwall by ferry, but these do not operate now. The Isles of Scilly are served by ferry (from Penzance) and by aeroplane, having its own airport: St Mary's Airport . There are regular flights between St Mary's and Land's End Airport , near St Just, and Newquay Airport ; during
700-673: A later group (Land's End, St Austell & Dartmoor). The early group of granites contain more aluminium than the later set and have steeper slopes on plots of cerium against yttrium . The later group contain more common basic microgranite xenoliths . The granites are generally rich in ammonium compared to average granites worldwide. There is also considerable variation between the individual plutons, with an average of 11 ppm for Dartmoor compared to 94 ppm for Bodmin Moor. The concentration of ammonium in these granites correlates well with both their initial Sr / Sr ratios and their peraluminosity . The relatively high ammonium content
800-735: A raid from the Tamar to Land's End, and the end of Cornish independence. However, the Anglo-Saxon Chronicle states that in 825 (adjusted date) a battle took place between the Wealas (Cornish) and the Defnas (men of Devon) at Gafulforda . The Cornish giving battle here, and the later battle at Hingston Down, casts doubt on any claims of control Wessex had at this stage. In 838, the Cornish and their Danish allies were defeated by Egbert in
900-628: A result, in 2005 its promoters received limited government funding. Several words originating in Cornish are used in the mining terminology of English, such as costean , gossan , gunnies , kibbal, kieve and vug . The Cornish language and culture influenced the emergence of particular pronunciations and grammar not used elsewhere in England. The Cornish dialect is spoken to varying degrees; however, someone speaking in broad Cornish may be practically unintelligible to one not accustomed to it. Cornish dialect has generally declined, as in most places it
1000-551: A very infertile soil which covers the flat and marshy heaths of the interior of the peninsula. This is home to rare plants, such as the Cornish Heath , which has been adopted as the county flower . Cornwall's only city, and the home of the council headquarters , is Truro. Nearby Falmouth is notable as a port. St Just in Penwith is the westernmost town in England, though the same claim has been made for Penzance , which
1100-742: Is a ceremonial county in South West England . It is recognised by Cornish and Celtic political groups as one of the Celtic nations , and is the homeland of the Cornish people . The county is bordered by the Atlantic Ocean to the north and west, Devon to the east, and the English Channel to the south. The largest urban area in the county is a conurbation that includes the former mining towns of Redruth and Camborne , and
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#17327873907531200-713: Is a large mass of granite rock, formed about 280 million years ago, which lies beneath much of Cornwall and Devon in the South West Peninsula of England . The main exposed masses of granite are seen at Dartmoor , Bodmin Moor , St Austell , Carnmenellis , Land's End and the Isles of Scilly . The intrusion is associated with significant quantities of minerals , particularly cassiterite , an ore of tin which has been mined since about 2000 BC. Other minerals include china clay and ores of copper , lead , zinc and tungsten . It takes its name from Cornubia ,
1300-403: Is by F. H. Davey Flora of Cornwall (1909). Davey was assisted by A. O. Hume and he thanks Hume, his companion on excursions in Cornwall and Devon, and for help in the compilation of that Flora, publication of which was financed by him. Cornwall has a temperate Oceanic climate ( Köppen climate classification : Cfb ), with mild winters and cool summers. Cornwall has the mildest and one of
1400-594: Is documented in a dedicated online journal. Local television programmes are provided by BBC South West & ITV West Country . Radio programmes are produced by BBC Radio Cornwall in Truro for the entire county, Heart West , Source FM for the Falmouth and Penryn areas, Coast FM for west Cornwall, Radio St Austell Bay for the St Austell area, NCB Radio for north Cornwall & Pirate FM . Cornwall has
1500-496: Is interpreted to be a sheet about 3 km thick with a near central root extending down to about 7 km depth. Boreholes at Rosemanowes that extend to over 2.5 km deep have shown very little variation in the petrographic composition of the granite with depth in this pluton. Monazite gives an emplacement age of 293.7±0.6 Ma for this pluton. The Tregonning Granite and Godolphin Granite are two distinct granite bodies on
1600-406: Is interpreted to indicate that the granites were derived from a sedimentary protolith, or have been contaminated from such a source after emplacement to high crustal levels. Around the edges of many of the plutons the country rocks have been transformed by heat in a process known as contact metamorphism . The effects of this can be seen up to a distance of 4 miles from the granite in an area called
1700-426: Is larger. St Ives and Padstow are today small vessel ports with a major tourism and leisure sector in their economies. Newquay on the north coast is another major urban settlement which is known for its beaches and is a popular surfing destination, as is Bude further north, but Newquay is now also becoming important for its aviation-related industries. Camborne is the county's largest town and more populous than
1800-402: Is no apparent systematic variation in age of plutons compared to their position within the batholith. This suggests that the batholith grew by the coalescence of a series of separate intrusions over a period of about 25 Ma. As with all large intrusive bodies, the method by which the batholith's plutons were emplaced is a matter of debate, due to the space problem of adding such large masses to
1900-416: Is now little more than a regional accent and grammatical differences have been eroded over time. Marked differences in vocabulary and usage still exist between the eastern and western parts of Cornwall. Saint Piran 's Flag is the national flag and ancient banner of Cornwall, and an emblem of the Cornish people. The banner of Saint Piran is a white cross on a black background (in terms of heraldry 'sable,
2000-401: Is often known as Pentewan stone (or by other names based on the location). Some older descriptions of building stones have called "white elvans" limestone, e.g. in studies of Lemon Street, Truro. Approximately 400 prehistoric stone axes, known as Group 1 axes and made from greenstone, have been found all over Britain, which from petrological analysis appear to come from west Cornwall. Although
2100-534: The Anglo-Saxon Chronicle in 891 as On Corn walum . In the Domesday Book it was referred to as Cornualia and in c. 1198 as Cornwal . Other names for the county include a latinisation of the name as Cornubia (first appears in a mid-9th-century deed purporting to be a copy of one dating from c. 705), and as Cornugallia in 1086. Cornwall forms the tip of the south-west peninsula of
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#17327873907532200-653: The A30 which connects Cornwall to the M5 motorway at Exeter , crosses the border south of Launceston , crosses Bodmin Moor and connects Bodmin, Truro, Redruth, Camborne, Hayle and Penzance. Torpoint Ferry links Plymouth with Torpoint on the opposite side of the Hamoaze . A rail bridge, the Royal Albert Bridge built by Isambard Kingdom Brunel (1859), provides the other main land transport link. The city of Plymouth,
2300-795: The Atlantic Bronze Age system, and which extended over most of the areas of present-day Ireland, England, Wales, France, Spain, and Portugal. During the British Iron Age , Cornwall, like all of Britain (modern England, Scotland, Wales, and the Isle of Man), was inhabited by a Celtic-speaking people known as the Britons with distinctive cultural relations to neighbouring Brittany . The Common Brittonic spoken at this time eventually developed into several distinct tongues, including Cornish , Welsh , Breton , Cumbric and Pictish . The first written account of Cornwall comes from
2400-511: The Battle of Hingston Down at Hengestesdune. In 875, the last recorded king of Cornwall, Dumgarth , is said to have drowned. Around the 880s, Anglo-Saxons from Wessex had established modest land holdings in the north eastern part of Cornwall; notably Alfred the Great who had acquired a few estates. William of Malmesbury , writing around 1120, says that King Athelstan of England (924–939) fixed
2500-733: The Bodmin Manumissions . One interpretation of the Domesday Book is that by this time the native Cornish landowning class had been almost completely dispossessed and replaced by English landowners, particularly Harold Godwinson himself. However, the Bodmin manumissions show that two leading Cornish figures nominally had Saxon names, but these were both glossed with native Cornish names. In 1068, Brian of Brittany may have been created Earl of Cornwall , and naming evidence cited by medievalist Edith Ditmas suggests that many other post-Conquest landowners in Cornwall were Breton allies of
2600-747: The Carboniferous Crackington and Bealsmill formations of Namurian to lower Westphalian age. This provides a lower bound for the timing of granite emplacement of about 310 Ma. The earliest instance of granitic clasts (fragments of the granite which have weathered away and become part of a new sedimentary rock) in younger sedimentary sequences is from the Late Permian St. Cyres beds . This gives an upper bound of about 250 Ma. The inferred age of emplacement from this evidence of Late Carboniferous to Early Permian has been confirmed by radiometric dating, although it has shown that
2700-542: The Celtic Sea , part of the Atlantic Ocean, is more exposed and therefore has a wilder nature. The High Cliff , between Boscastle and St Gennys , is the highest sheer-drop cliff in Cornwall at 223 metres (732 ft). Beaches, which form an important part of the tourist industry, include Bude , Polzeath , Watergate Bay , Perranporth , Porthtowan , Fistral Beach , Newquay , St Agnes , St Ives , and on
2800-552: The Chappell & White classification as being S-type , which means that they are ultimately derived from sedimentary rock protolith . The Cornubian intrusions are mostly made up of two- mica granite (containing both muscovite and biotite ). Li -mica granite forms a less common type found only in the St. Austell pluton and some smaller intrusions. Many of the granites contain large alkali feldspar phenocrysts. In some locations
2900-565: The Cornish language , Cornwall is Kernow which stems from the same Proto-Celtic root. Humans reoccupied Britain after the last Ice Age . The area now known as Cornwall was first inhabited in the Palaeolithic and Mesolithic periods. It continued to be occupied by Neolithic and then by Bronze Age people. Cornwall in the Late Bronze Age formed part of a maritime trading-networked culture which researchers have dubbed
3000-588: The Dumnonii often came into conflict with the expanding English kingdom of Wessex . Centwine of Wessex "drove the Britons as far as the sea" in 682, and by 690 St Bonifice , then a Saxon boy, was attending an abbey in Exeter, which was in turn ruled by a Saxon abbot. The Carmen Rhythmicum written by Aldhelm contains the earliest literary reference to Cornwall as distinct from Devon. Religious tensions between
3100-515: The Dumnonii , three of which may have been in Cornwall. However, after 410 AD, Cornwall appears to have reverted to rule by Romano-Celtic chieftains of the Cornovii tribe as part of the Brittonic kingdom of Dumnonia (which also included present-day Devonshire and the Scilly Isles), including the territory of one Marcus Cunomorus , with at least one significant power base at Tintagel in
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3200-532: The Industrial Revolution , the tin and copper mines were expanded and then declined, with china clay extraction becoming a major industry. Railways were built, leading to a growth of tourism in the 20th century. The Cornish language became extinct as a living community language at the end of the 18th century , but is now being revived. The modern English name "Cornwall" is a compound of two terms coming from two different language groups: In
3300-578: The Medieval Latin name for Cornwall. A batholith is a large mass of intrusive rock formed from the crystallization of molten rock beneath the Earth's surface ( magma ). From gravity and magnetic geophysical data , the batholith is interpreted to extend from about 8°W, more than 100 km southwest of the Isles of Scilly, to the eastern edge of Dartmoor. The negative gravity anomaly, caused by
3400-457: The River Looe are both popular with tourists. The interior of the county consists of a roughly east–west spine of infertile and exposed upland, with a series of granite intrusions, such as Bodmin Moor , which contains the highest land within Cornwall. From east to west, and with approximately descending altitude, these are Bodmin Moor, Hensbarrow north of St Austell , Carnmenellis to
3500-506: The constitutional status of Cornwall and seeks greater autonomy within the United Kingdom. Cornwall is the westernmost part of the South West Peninsula , and the southernmost county within the United Kingdom. Its coastline is characterised by steep cliffs and, to the south, several rias , including those at the mouths of the rivers Fal and Fowey . It includes the southernmost point on Great Britain , Lizard Point , and forms
3600-528: The county town is the city of Truro . The county is rural, with an area of 1,375 square miles (3,562 km ) and population of 568,210. Outside of the Redruth-Camborne conurbation the largest settlements are Falmouth , Penzance , Newquay , St Austell , and Truro. For local government purposes most of Cornwall is a unitary authority area, with the Isles of Scilly having a unique local authority . The Cornish nationalist movement disputes
3700-481: The sub-Roman Westcountry , South Wales, Brittany, the Channel Islands, and Ireland through the fifth and sixth centuries. In Cornwall, the arrival of Celtic saints such as Nectan , Paul Aurelian, Petroc , Piran , Samson and numerous others reinforced the preexisting Roman Christianity. The Battle of Deorham in 577 saw the separation of Dumnonia (and therefore Cornwall) from Wales, following which
3800-460: The "Cornish Riviera", is more sheltered and there are several broad estuaries offering safe anchorages, such as at Falmouth and Fowey . Beaches on the south coast usually consist of coarser sand and shingle, interspersed with rocky sections of wave-cut platform . Also on the south coast, the picturesque fishing village of Polperro , at the mouth of the Pol River, and the fishing port of Looe on
3900-424: The 1st-century BC Sicilian Greek historian Diodorus Siculus , supposedly quoting or paraphrasing the 4th-century BCE geographer Pytheas , who had sailed to Britain: The inhabitants of that part of Britain called Belerion (or Land's End) from their intercourse with foreign merchants, are civilized in their manner of life. They prepare the tin , working very carefully the earth in which it is produced ... Here then
4000-551: The AHS Heat Zone 1. Extreme temperatures in Cornwall are particularly rare; however, extreme weather in the form of storms and floods is common. Due to climate change Cornwall faces more heatwaves and severe droughts, faster coastal erosion, stronger storms and higher wind speeds as well as the possibility of more high-impact flooding. Cornish, a member of the Brythonic branch of the Celtic language family , died out as
4100-690: The Carnmenellis, Bodmin and Isles of Scilly, whereas the younger biotite and tourmaline granites are found within the Land's End, St. Austell and Dartmoor plutons. Topaz granites outcrop within the Tregonning, Land's End and St Austell plutons. This is the largest exposed area of granite which also forms the easternmost development of the batholith. The granite consists of two main types, coarse-grained granite with abundant large alkali feldspar megacrysts and coarse-grained granite with few megacrysts. To
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4200-467: The Cornubian batholith the granites here are fine to medium-grained and generally lack megacrysts. It was intruded at 277 Ma and is considered most likely to be a separate but related intrusive body that runs parallel to the Cornubian batholith. Minor granitic intrusions are present throughout the peninsula. In some cases granitic bodies have been recognised from the mineralization above them, even if
4300-785: The Dartmoor area). The stannary courts administered equity for the region's tin-miners and tin mining interests, and they were also courts of record for the towns dependent on the mines. The separate and powerful government institutions available to the tin miners reflected the enormous importance of the tin industry to the English economy during the Middle Ages. Special laws for tin miners pre-date written legal codes in Britain, and ancient traditions exempted everyone connected with tin mining in Cornwall and Devon from any jurisdiction other than
4400-784: The Dumnonians (who celebrated celtic Christian traditions) and Wessex (who were Roman Catholic ) are described in Aldhelm's letter to King Geraint . The Annales Cambriae report that in AD 722 the Britons of Cornwall won a battle at "Hehil" . It seems likely that the enemy the Cornish fought was a West Saxon force, as evidenced by the naming of King Ine of Wessex and his kinsman Nonna in reference to an earlier Battle of Llongborth in 710. The Anglo-Saxon Chronicle stated in 815 (adjusted date) "and in this year king Ecgbryht raided in Cornwall from east to west." this has been interpreted to mean
4500-453: The Lizard peninsula is unusual, in that it is mainland Britain's only example of an ophiolite , a section of oceanic crust now found on land. Much of the peninsula consists of the dark green and red Precambrian serpentinite , which forms spectacular cliffs, notably at Kynance Cove , and carved and polished serpentine ornaments are sold in local gift shops. This ultramafic rock also forms
4600-704: The Normans, the Bretons being descended from Britons who had fled to what is today Brittany during the early years of the Anglo-Saxon conquest. She also proposed this period for the early composition of the Tristan and Iseult cycle by poets such as Béroul from a pre-existing shared Brittonic oral tradition. Soon after the Norman conquest most of the land was transferred to the new Breton–Norman aristocracy, with
4700-575: The Phoenicians sailed to Cornwall. In fact, he says quite the opposite: the production of Cornish tin was in the hands of the natives of Cornwall, and its transport to the Mediterranean was organized by local merchants, by sea and then overland through France, passing through areas well outside Phoenician control." Isotopic evidence suggests that tin ingots found off the coast of Haifa , Israel , may have been from Cornwall. Tin, required for
4800-492: The Roman road system extended into Cornwall with four significant Roman sites based on forts: Tregear near Nanstallon was discovered in the early 1970s, two others were found at Restormel Castle , Lostwithiel in 2007, and a third fort near Calstock was also discovered early in 2007. In addition, a Roman-style villa was found at Magor Farm , Illogan in 1935. Ptolemy 's Geographike Hyphegesis mentions four towns controlled by
4900-618: The South West increasingly came into conflict with the expanding Anglo-Saxon kingdom of Wessex , eventually being pushed west of the Tamar; by the Norman Conquest Cornwall was administered as part of England, though it retained its own culture. The remainder of the Middle Ages and Early Modern Period were relatively settled, with Cornwall developing its tin mining industry and becoming a duchy in 1337. During
5000-635: The St Austell area on 1 April 2009 St Austell was the largest settlement in Cornwall. Cornwall borders the county of Devon at the River Tamar. Major roads between Cornwall and the rest of Great Britain are the A38 which crosses the Tamar at Plymouth via the Tamar Bridge and the town of Saltash , the A39 road (Atlantic Highway) from Barnstaple , passing through North Cornwall to end in Falmouth, and
5100-400: The batholith had an overall trapezoidal shape with a base to the batholith at about 10–12 km. However, current understanding of granite pluton shape suggest that most are either laccolithic or lopolithic . Comparisons with other examples would suggest that the thicknesses of the individual plutons would be in the range 3–5 km, based on their outcrop widths. The volume of
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#17327873907535200-562: The batholith was estimated in 1989 to be around 68,000 cubic kilometres. The Cornubian batholith formed during the Early Permian period, from about 300 to 275 Ma (million years ago) at a late stage in the mountain-building event known as the Variscan orogeny as a suite of late orogenic granites. It has been suggested that stretching of the Earth's crust ( crustal extension ) allowed the granitic magmas to move to higher levels in
5300-496: The boundary between English and Cornish people at the east bank of the River Tamar . While elements of William's story, like the burning of Exeter , have been cast in doubt by recent writers Athelstan did re-establish a separate Cornish Bishop and relations between Wessex and the Cornish elite improved from the time of his rule. Eventually King Edgar was able to issue charters the width of Cornwall, and frequently sent emissaries or visited personally as seen by his appearances in
5400-442: The coast and are also rare in the central upland areas. Summers are, however, not as warm as in other parts of southern England. The surrounding sea and its southwesterly position mean that Cornwall's weather can be relatively changeable. Cornwall is one of the sunniest areas in the UK. It has more than 1,541 hours of sunshine per year, with the highest average of 7.6 hours of sunshine per day in July. The moist, mild air coming from
5500-415: The conduit that carried the magma to shallow crustal levels. It appears to have been intruded along the interface between Devonian and Carboniferous rocks. Uranium-lead dating of Monazite from this intrusion gives emplacement ages of 278.2±0.8 Ma and 280.4±1.2 Ma. The Bodmin Moor pluton consists mainly of coarse-grained granite with abundant small megacrysts. Towards the centre and the western margin of
5600-501: The country-rock. Although the Land's End pluton was once thought to have a diapiric origin, its emplacement is now interpreted to have been accommodated by fault movements during regional extension. The individual plutons that comprise the Cornubian Batholith can be broadly subdivided into five main lithologies: Two mica, Muscovite, Biotite, Tourmaline and Topaz granites, each named for their distinguishing mineral(s). The two-mica and muscovite granites are older, and can be found in
5700-424: The county town Truro. Together with the neighbouring town of Redruth , it forms the largest urban area in Cornwall, and both towns were significant as centres of the global tin mining industry in the 19th century; nearby copper mines were also very productive during that period. St Austell is also larger than Truro and was the centre of the china clay industry in Cornwall. Until four new parishes were created for
5800-416: The crust. Evidence from neodymium and strontium isotopes suggests that the magmas that formed the batholith were mainly the result of partial melting of the lower crust with a minor component of basaltic magma from a mantle source. This lower crustal source is likely to have consisted of both metasedimentary and metavolcanic rocks, of Proterozoic age (2500 million to 539 million years old). As
5900-586: The early 6th century. King Mark of Cornwall is a semi-historical figure known from Welsh literature, from the Matter of Britain , and, in particular, from the later Norman-Breton medieval romance of Tristan and Yseult , where he appears as a close relative of King Arthur , himself usually considered to be born of the Cornish people in folklore traditions derived from Geoffrey of Monmouth 's 12th-century Historia Regum Britanniae . Archaeology supports ecclesiastical, literary and legendary evidence for some relative economic stability and close cultural ties between
6000-426: The elvan quarries are now disused. Others are quarried in bulk for aggregates commonly used for road-building. More precisely there are two types of rock in this category: one is "white elvan" and the other is "blue elvan". "White elvans" are a group of fine-grained, acid igneous rocks, while "blue elvans" or "greenstones" are various unusual basic igneous rocks. "White elvan" comes from various different locations and
6100-401: The formation of hornblende - plagioclase rocks. A feature of the granites of the batholith is the high concentrations of volatile components. Fluids rich in these have strongly affected the country rock and locally the granites themselves in a process called metasomatism. The first phase recognised is alkali metasomatism (where alkaline components are enhanced), which occurred within and at
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#17327873907536200-414: The granite erodes further, blocks of eroded granite known as clitter are left. An approximate age of emplacement for the Cornubian batholith was known before radiometric dating methods became commonplace, from the observed relationships with the sedimentary rocks – both those which formed before the intrusion and those which were laid down after it. The youngest rocks into which the granites intrude are
6300-434: The granite slowly cooled. Each stage is associated with different temperatures, economic deposits of different metals and different gangue minerals. The first three stages have been connected to the intrusion and cooling of the batholith, while the fourth stage may have been driven by the heat production associated with radioactive materials in the granite. Large economic deposits of china clay are found in places across
6400-439: The hot granite as it cooled and are typically found in veins or washed into streams to form alluvium . The mineral deposits are associated with multiple lodes and fractures that dip steeply and cut across both the granites and the country rocks. The ore-bearing lodes are up to several kilometres long and are 0.5 to 3m wide on average. There are four recognised stages of mineralization associated with different conditions as
6500-409: The individual intrusions were emplaced over a significant time interval. The earliest dated major intrusion is the Carnmenellis pluton at 293.1±3 Ma. The youngest dated granite is the southern lobe of the Land's End pluton, intruded at 274.5±1.4 Ma. The earliest recorded magmatic activity is the intrusion of the small Hemerdon pluton on the southwestern flank of the Dartmoor pluton at 298.3±2.3 Ma. There
6600-438: The intrusion itself has not been encountered. A series of minor intrusions are found within the country rock and the granites themselves. Common types are pegmatites , aplites and elvans . The main rock forming the batholith is granite , which formed when magma cooled slowly, covered by 2–3,000 metres of slate and sandstone. The slow cooling gave time for crystals to form in the granite which are large enough to see with
6700-489: The island of Great Britain , and is therefore exposed to the full force of the prevailing winds that blow in from the Atlantic Ocean. The coastline is composed mainly of resistant rocks that give rise in many places to tall cliffs. Cornwall has a border with only one other county, Devon , which is formed almost entirely by the River Tamar , and the remainder (to the north) by the Marsland Valley . The north and south coasts have different characteristics. The north coast on
6800-401: The lion's share going to Robert, Count of Mortain , half-brother of King William and the largest landholder in England after the king with his stronghold at Trematon Castle near the mouth of the Tamar. Subsequently, however, Norman absentee landlords became replaced by a new Cornish-Norman ruling class including scholars such as Richard Rufus of Cornwall . These families eventually became
6900-407: The main coarse-grained granite respectively. These give emplacement ages of 279.3±0.4 Ma for the fine-grained granite and 274.8±0.5 Ma for the main phase granite. This difference is consistent with fine-grained granite being a roof-pendant to the coarse-grained main phase granite intrusion. The Isles of Scilly all have granite bedrock. The dominant rock type is a megacrystic biotite granite, although
7000-481: The margins of the granite. Potassium – metasomatism was followed by sodium –metasomatism. Finally acid metasomatism (enrichment of acid components and depletion of alkalis) took place leading to the formation of greisen and tourmalines. Large mineral deposits are found in the vicinity of the batholith and these have been mined for thousands of years. The area has been famous for its tin since about 2000 BC. The minerals formed when fluids escaped along fractures in
7100-430: The megacrysts are relatively small. In the centre of the pluton a medium-grained granite is developed with few megacrysts, more tourmaline and less biotite than the main variety. Monazite from this pluton suggest an emplacement age of 290.3±0.6 Ma. This submarine outcrop, 45 km in length, lies 95 km northwest of the Scilly Isles, rising at one point to 38 m below sea level. In contrast to most granites of
7200-509: The merchants buy the tin from the natives and carry it over to Gaul , and after traveling overland for about thirty days, they finally bring their loads on horses to the mouth of the Rhône. The identity of these merchants is unknown. It has been theorized that they were Phoenicians , but there is no evidence for this. Professor Timothy Champion, discussing Diodorus Siculus's comments on the tin trade, states that "Diodorus never actually says that
7300-483: The metamorphic aureole. The effect of this process depends on the type of rocks which were heated and their distance from the intrusion. Fine grained sedimentary rocks were transformed into hornfels and minerals such as amphibole , pyroxene . At greater distances from the plutons, the only evidence of metamorphism is spotting in these rocks. Garnet developed in calcareous rocks as well as amphibole and pyroxene . The metamorphism of greenstones has generally led to
7400-482: The molten rock cooled to around 1000 Celsius it solidified and crystallised and fractures along vertical joints formed. Over time the slate and sandstone rocks covering the granite were eroded exposing the granite in areas such as Dartmoor and Bodmin Moor. The granite also expanded and horizontal joints were formed. These joints are most clearly seen on exposed pieces of rock such as the Tors of Dartmoor and Bodmin Moor. As
7500-586: The most important mining areas in Europe until the early 20th century. It is thought tin was mined here as early as the Bronze Age , and copper, lead, zinc and silver have all been mined in Cornwall . Alteration of the granite also gave rise to extensive deposits of China Clay , especially in the area to the north of St Austell, and the extraction of this remains an important industry. The uplands are surrounded by more fertile, mainly pastoral farmland. Near
7600-443: The naked eye, giving it a granular appearance. These grains are mainly of quartz , feldspar and biotite . The granite is generally coarse grained and in some places very coarse-grained, or pegmatitic (grains larger than 3 cm). Large phenocrysts , several centimetres long, of K-feldspar, are a distinctive feature. The chemistry and mineralogy of the granites vary from one location to another, but they are all classified on
7700-406: The nearby Carnmenellis Granite, although is finer grained. The Land's End pluton is mainly a coarse-grained granite with abundant large megacrysts. There is an area in the centre which is poor in megacrysts and there are several small and medium-sized masses of fine-grained granite throughout the outcrop. Dating has been carried out on xenotime and monazite samples, from a fine-grained granite and
7800-744: The new rulers of Cornwall, typically speaking Norman French , Breton-Cornish, Latin , and eventually English, with many becoming involved in the operation of the Stannary Parliament system, the Earldom and eventually the Duchy of Cornwall . The Cornish language continued to be spoken and acquired a number of characteristics establishing its identity as a separate language from Breton . The stannary parliaments and stannary courts were legislative and legal institutions in Cornwall and in Devon (in
7900-651: The original granite has been modified to form a tourmaline -bearing granite called luxullianite . This tourmalinisation occurred during the late stages of cooling of the granite, as feldspar and mica were partly replaced by tourmaline. The two-mica granites are strongly peraluminous – they have a high ratio of aluminium oxide to sodium and potassium oxides. They also have a low ratio of sodium to potassium and overall high level of alkalis. The granites are highly enriched in lithium , boron , caesium and uranium and moderately so in fluorine , gallium , germanium , rubidium , tin, tantalum , tungsten and thallium . Given
8000-428: The outcrop there are smaller bodies of fine-grained granite. Gravity data suggest that this pluton is in the form of a south-southeastward thickening wedge, reaching a maximum of about 7 km. Monazite from this pluton gives an emplacement age of 291.4±0.8 Ma. The St Austell pluton consists of coarse-grained megacrystic granite with large megacrysts at the western and eastern ends of the outcrop. The central part of
8100-586: The overall chemistry, the levels of phosphorus are also high. Strontium, barium and the elements from scandium to zinc are relatively depleted. This chemistry is consistent with partial melting of a source consisting of greywackes (a variety of sandstone). The conditions under which the melts formed is modelled to be temperature of 770 °C and a confining pressure of 50 MPa . Differences in chemistry have been identified between an earlier group of plutons (Isles of Scilly, Carnmenellis & Bodmin Moor) and
8200-514: The pluton is also coarse-grained but lacks the megacrysts. Between the central megacryst poor and the large megacryst rich coarse-grained granites at the western end, a medium-grained granite is developed with lithium-mica. Smaller bodies of fine-grained granite are found in the central part of the outcrop and at the western end. Gravity data indicate that this pluton is wedge-shaped similar to that at Bodmin. Monazite gives an emplacement age of 281.8±0.4 Ma for this pluton. The Carnmenellis pluton and
8300-512: The production of bronze , was a relatively rare and precious commodity in the Bronze Age – hence the interest shown in Devon and Cornwall's tin resources. (For further discussion of tin mining see the section on the economy below .) In the first four centuries AD, during the time of Roman dominance in Britain , Cornwall was rather remote from the main centres of Romanization – the nearest being Isca Dumnoniorum , modern-day Exeter . However,
8400-550: The publication in 1904 of Henry Jenner 's Handbook of the Cornish Language . It is a social networking community language rather than a social community group language. Cornwall Council encourages and facilitates language classes within the county, in schools and within the wider community. In 2002, Cornish was named as a UK regional language in the European Charter for Regional or Minority Languages . As
8500-502: The quarry has not been identified, it has been suggested that the Gear ( grid reference SW479293 ), a rock now submerged half a mile from the shore at Penzance , may be the site. A significant amount of trade is indicated as many have been found elsewhere in Britain. Cornwall Cornwall ( / ˈ k ɔːr n w ɔː l , - w əl / ; Cornish : Kernow ; Cornish pronunciation: [ˈkɛrnɔʊ] ; or [ˈkɛrnɔ] )
8600-582: The relatively low density of the granites compared to average continental crust , is linear and trends WSW-ENE, parallel with that associated with the Haig Fras granite. The shape of the batholith and the relationship between the individual plutons and the main mass of the granite remained entirely speculative until gravity data began to be used to constrain the thickness and shape of the batholith by modelling. The initial work by Martin Bott suggested that
8700-784: The sculptor Barbara Hepworth , at the outbreak of the Second World War . They were later joined by the Russian emigrant Naum Gabo , and other artists. These included Peter Lanyon , Terry Frost , Patrick Heron , Bryan Wynter and Roger Hilton . St Ives also houses the Leach Pottery, where Bernard Leach , and his followers championed Japanese inspired studio pottery. Much of this modernist work can be seen in Tate St Ives . The Newlyn Society and Penwith Society of Arts continue to be active, and contemporary visual art
8800-546: The smaller intrusion of Carn Brea appear to be part of a single intrusive body. The central part of the Carnmenellis outcrop is a medium-grained granite with few megacrysts. The bulk of the main outcrop and the Carn Brea and Carn Marth masses consist of coarse-grained megacrystic granite with small megacrysts. Small bodies of fine-grained granite are found towards the west of the Carnemellis outcrop. The shape of this pluton
8900-584: The south coast Gyllyngvase beach in Falmouth and the large beach at Praa Sands further to the south-west. There are two river estuaries on the north coast: Hayle Estuary and the estuary of the River Camel , which provides Padstow and Rock with a safe harbour. The seaside town of Newlyn is a popular holiday destination, as it is one of the last remaining traditional Cornish fishing ports, with views reaching over Mount's Bay. The south coast, dubbed
9000-493: The south coast, deep wooded valleys provide sheltered conditions for flora that like shade and a moist, mild climate. These areas lie mainly on Devonian sandstone and slate . The north east of Cornwall lies on Carboniferous rocks known as the Culm Measures . In places these have been subjected to severe folding, as can be seen on the north coast near Crackington Haven and in several other locations. The geology of
9100-568: The south of Camborne , and the Penwith or Land's End peninsula. These intrusions are the central part of the granite outcrops that form the exposed parts of the Cornubian batholith of south-west Britain, which also includes Dartmoor to the east in Devon and the Isles of Scilly to the west, the latter now being partially submerged. The intrusion of the granite into the surrounding sedimentary rocks gave rise to extensive metamorphism and mineralisation , and this led to Cornwall being one of
9200-409: The south-west peninsula, in particular Lee Moor on the western edge of Dartmoor and the St Austell district. The china clay was formed by the alteration of feldspars in a process known as kaolinization. There is still debate about the origin and age of these deposits but they are commonly thought to arise from the circulation of meteoric water (water from rain or snow) at a late stage during cooling of
9300-403: The southern coast of Cornwall. The Tregonning Granite is mainly a medium-grained lithium-mica granite with a body of fine-grained granite developed towards the northwest of the outcrop. It has a unique chemistry and differs from the granite found within the Carnmenellis and Land's End granites, likely forming in a different manner. The Godolphin Granite is mineralogically and chemically similar to
9400-541: The southwest brings higher amounts of rainfall than in eastern Great Britain, at 1,051 to 1,290 mm (41.4 to 50.8 in) per year. However, this is not as much as in more northern areas of the west coast. The Isles of Scilly, for example, where there are on average fewer than two days of air frost per year, is the only area in the UK to be in the Hardiness zone 10. The islands have, on average, less than one day of air temperature exceeding 30 °C per year and are in
9500-402: The southwest there is an area of coarse-grained granite with small megacrysts and several small exposures of fine-grained granite, particularly in the southeastern part of the outcrop. Interpretation of the gravity field over this pluton suggests that it is sheet-like with a thickness of nearly 10 km, and a root at its southern end extending down to about 17 km depth, which may represent
9600-609: The stannary courts in all but the most exceptional circumstances. Cornish piracy was active during the Elizabethan era on the west coast of Britain. Cornwall is well known for its wreckers who preyed on ships passing Cornwall's rocky coastline. During the 17th and 18th centuries Cornwall was a major smuggling area. In later times, Cornwall was known to the Anglo-Saxons as "West Wales" to distinguish it from "North Wales" (the modern nation of Wales ). The name appears in
9700-500: The summer season, a service is also provided between St Mary's and Exeter Airport , in Devon. Cornwall has varied habitats including terrestrial and marine ecosystems. One noted species in decline locally is the Reindeer lichen , which species has been made a priority for protection under the national UK Biodiversity Action Plan . Botanists divide Cornwall and Scilly into two vice-counties: West (1) and East (2). The standard flora
9800-480: The sunniest climates of the United Kingdom, as a result of its oceanic setting and the influence of the Gulf Stream . The average annual temperature in Cornwall ranges from 11.6 °C (52.9 °F) on the Isles of Scilly to 9.8 °C (49.6 °F) in the central uplands. Winters are among the warmest in the country due to the moderating effects of the warm ocean currents, and frost and snow are very rare at
9900-414: The upper crust. Four main mechanisms have been proposed; stoping , diapirism , extensional faulting and uplift of the overlying country rock over a laccolithic sill with a relatively small vertical dyke feeder. Evidence for a stoping mechanism has been described locally from the margin of the Tregonning intrusion, where a series of intrusive sheets extend out from the roof zone of the intrusion into
10000-491: Was initially centred on the art-colony of Newlyn , most active at the turn of the 20th century. This Newlyn School is associated with the names of Stanhope Forbes , Elizabeth Forbes , Norman Garstin and Lamorna Birch . Modernist writers such as D. H. Lawrence and Virginia Woolf lived in Cornwall between the wars, and Ben Nicholson , the painter, having visited in the 1920s came to live in St Ives with his then wife,
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