Blueis one of the threeprimary coloursin theRYB colour model(traditional colour theory), as well as in theRGB (additive) colour model.[2]It lies betweenvioletandcyanon thespectrumofvisible light.The termbluegenerally describes colours perceived by humans observing light with adominant wavelengththat's between approximately 450 and 495nanometres.Most blues contain a slight mixture of other colours;azurecontains some green, whileultramarinecontains some violet. The clear daytime sky and the deep sea appear blue because of an optical effect known asRayleigh scattering.An optical effect called theTyndall effectexplainsblue eyes.Distant objects appear more blue because of another optical effect calledaerial perspective.
Blue | |
---|---|
Spectral coordinates | |
Wavelength | approx. 450–495nm |
Frequency | ~670–610THz |
Colour coordinates | |
Hex triplet | #0000FF |
sRGBB(r,g,b) | (0, 0, 255) |
HSV(h,s,v) | (240°, 100%, 100%) |
CIELChuv(L,C,h) | (32, 131, 266°) |
Source | HTML/CSS[1] |
B:Normalized to [0–255] (byte) H:Normalized to [0–100] (hundred) |
Blue has been an important colour in art and decoration since ancient times. The semi-precious stonelapis lazuliwas used in ancient Egypt for jewellery and ornament and later, in theRenaissance,to make the pigmentultramarine,the most expensive of all pigments.[3]In the eighth century Chinese artists usedcobalt blueto colour fineblue and white porcelain.In theMiddle Ages,European artists used it in the windows ofcathedrals.Europeans wore clothing coloured with the vegetable dyewoaduntil it was replaced by the finerindigofrom America. In the 19th century, synthetic blue dyes and pigments gradually replaced organic dyes and mineral pigments. Dark blue became a common colour for military uniforms and later, in the late 20th century, for business suits. Because blue has commonly been associated with harmony, it was chosen as the colour of the flags of theUnited Nationsand theEuropean Union.[4]
In the United States and Europe, blue is the colour that both men and women are most likely to choose as their favourite, with at least one recent survey showing the same across several other countries, including China, Malaysia, and Indonesia.[5][6]Past surveys in the US and Europe have found that blue is the colour most commonly associated withharmony,confidence,masculinity,knowledge,intelligence,calmness,distance,infinity,theimagination,cold,andsadness.[7]
Etymology and linguistics
Themodern Englishwordbluecomes fromMiddle Englishbleuorblewe,from theOld Frenchbleu,a word ofGermanicorigin, related to theOld High Germanwordblao(meaning 'shimmering, lustrous').[8]Inheraldry,the wordazureis used forblue.[9]
InRussian,Spanish,[10]Mongolian,Irish,and some other languages, there is no single word for blue, but rather different words for light blue (голубой,goluboj;Celeste) and dark blue (синий,sinij;Azul) (seeColour term).
Several languages, includingJapaneseandLakota Sioux,use the same word to describe blue and green. For example, inVietnamese,the colour of both tree leaves and the sky isxanh.In Japanese, the word for blue (Thanh,ao) is often used for colours that English speakers would refer to as green, such as the colour of atraffic signalmeaning "go". In Lakota, the wordtȟóis used for both blue and green, the two colours not being distinguished in older Lakota (for more on this subject, seeBlue–green distinction in language).
Linguistic research indicates that languages do not begin by having a word for the colour blue.[11]Colour names often developed individually in natural languages, typically beginning withblackandwhite(or dark and light), and then addingred,and only much later – usually as the last main category of colour accepted in a language – adding the colour blue, probably when blue pigments could be manufactured reliably in the culture using that language.[11]
Optics and colour theory
The termbluegenerally describes colours perceived by humans observing light with adominant wavelengthbetween approximately 450 and 495 nanometres.[12]Blues with a higher frequency and thus a shorter wavelength gradually look more violet, while those with a lower frequency and a longer wavelength gradually appear more green. Purer blues are in the middle of this range, e.g., around 470 nanometres.
Isaac Newtonincluded blue as one of the seven colours in his first description of thevisible spectrum.[13]He chose seven colours because that was the number of notes in the musical scale, which he believed was related to the optical spectrum. He includedindigo,the hue between blue and violet, as one of the separate colours, though today it is usually considered a hue of blue.[14]
In painting and traditionalcolour theory,blue is one of the threeprimary coloursof pigments (red, yellow, blue), which can be mixed to form a widegamutof colours. Red and blue mixed together form violet, blue and yellow together form green. Mi xing all three primary colours together produces a dark brown. From the Renaissance onward, painters used this system to create their colours (seeRYB colour model).
The RYB model was used forcolour printingbyJacob Christoph Le Blonas early as 1725. Later, printers discovered that more accurate colours could be created by using combinations of cyan, magenta, yellow, and black ink, put onto separate inked plates and then overlaid one at a time onto paper. This method could produce almost all the colours in thespectrumwith reasonable accuracy.
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Additive colour mi xing. The combination ofprimary coloursproduces secondary colours where two overlap; the combination red, green, and blue each in full intensity makes white.
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Red, green, and bluesubpixelson aliquid-crystal display.
On theHSV colour wheel,thecomplementof blue isyellow;that is, a colour corresponding to an equal mixture ofredandgreenlight. On a colour wheel based on traditional colour theory (RYB) where blue was considered a primary colour, its complementary colour is considered to beorange(based on theMunsell colour wheel).[15]
LED
In 1993, high-brightness blue LEDs were demonstrated byShuji NakamuraofNichia Corporation.[16][17][18]In parallel,Isamu AkasakiandHiroshi AmanoofNagoya Universitywere working on a new development which revolutionized LED lighting.[19][20]
Nakamura was awarded the 2006Millennium Technology Prizefor his invention.[21] Nakamura,Hiroshi AmanoandIsamu Akasakiwere awarded theNobel Prize in Physicsin 2014 for the invention of an efficient blue LED.[22]
Lasers
Lasersemitting in the blue region of the spectrum became widely available to the public in 2010 with the release of inexpensive high-powered 445–447 nmlaser diodetechnology.[23]Previously the blue wavelengths were accessible only throughDPSSwhich are comparatively expensive and inefficient, but still widely used by scientists for applications includingoptogenetics,Raman spectroscopy,andparticle image velocimetry,due to their superior beam quality.[24]Bluegas lasersare also still commonly used forholography,DNA sequencing,optical pumping,among other scientific and medical applications.
Shades and variations
Blue is the colour of light betweenvioletandcyanon thevisible spectrum.Hues of blue include indigo andultramarine,closer to violet; pure blue, without any mixture of other colours; Azure, which is a lighter shade of blue, similar to the colour of the sky; Cyan, which is midway in the spectrum between blue andgreen,and the other blue-greens such asturquoise,teal,andaquamarine.
Blue also varies in shade or tint; darker shades of blue contain black or grey, while lighter tints contain white. Darker shades of blue include ultramarine,cobalt blue,navy blue,andPrussian blue;while lighter tints includesky blue,azure,andEgyptian blue(for a more complete list see theList of colours).
As a structural colour
In nature, many blue phenomena arise fromstructural colouration,the result of interference between reflections from two or more surfaces ofthin films,combined with refraction as light enters and exits such films. The geometry then determines that at certain angles, the light reflected from both surfaces interferes constructively, while at other angles, the light interferes destructively. Diverse colours therefore appear despite the absence of colourants.[25]
Colourants
Artificial blues
Egyptian blue,the first artificial pigment, was produced in the third millennium BC in Ancient Egypt. It is produced by heating pulverized sand, copper, andnatron.It was used in tomb paintings and funereal objects to protect the dead in their afterlife. Prior to the 1700s, blue colourants for artwork were mainly based on lapis lazuli and the related mineral ultramarine. A breakthrough occurred in 1709 when German druggist and pigment makerJohann Jacob DiesbachdiscoveredPrussian blue.The new blue arose from experiments involving heating dried blood with iron sulphides and was initially called Berliner Blau. By 1710 it was being used by the French painterAntoine Watteau,and later his successorNicolas Lancret.It became immensely popular for the manufacture of wallpaper, and in the 19th century was widely used by French impressionist painters.[26]Beginning in the 1820s, Prussian blue was imported into Japan through the port ofNagasaki.It was calledbero-ai,or Berlin blue, and it became popular because it did not fade like traditional Japanese blue pigment,ai-gami,made from thedayflower.Prussian blue was used by bothHokusai,in his wave paintings, andHiroshige.[27]
In 1799 a French chemist,Louis Jacques Thénard,made a synthetic cobalt blue pigment which became immensely popular with painters.
In 1824 theSocieté pour l'Encouragement d'Industriein France offered a prize for the invention of an artificialultramarinewhich could rival the natural colour made from lapis lazuli. The prize was won in 1826 by a chemist named Jean Baptiste Guimet, but he refused to reveal the formula of his colour. In 1828, another scientist,Christian Gmelinthen a professor of chemistry in Tübingen, found the process and published his formula. This was the beginning of new industry to manufacture artificial ultramarine, which eventually almost completely replaced the natural product.[28]
In 1878 German chemists synthesizedindigo.This product rapidly replaced natural indigo, wiping out vast farms growing indigo. It is now the blue of blue jeans. As the pace oforganic chemistryaccelerated, a succession of synthetic blue dyes were discovered includingIndanthrone blue,which had even greater resistance to fading during washing or in the sun, andcopper phthalocyanine.
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The Blue Boy(1770), featuring lapis lazuli, indigo, and cobalt colourants,[29]
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The Great Wave off Kanagawaillustrates the use ofPrussian blue
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A synthetic indigo dye factory in Germany in 1890.
Dyes for textiles and food
[30]Woadandtrue indigowere once used but since the early 1900s, all indigo is synthetic. Produced on an industrial scale, indigo is the blue of blue jeans. Blue dyes are organic compounds, both synthetic and natural.
For food, the triarylmethane dyeBrilliant blue FCFis used for candies. The search continues for stable, natural blue dyes suitable for the food industry.[30]
Variousraspberry-flavoured foods are dyed blue. This was done to distinguishstrawberry,watermelonandraspberry-flavoured foods.[31]The companyICEEused Blue No. 1 for their blue raspberry ICEEs.
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Blue Raspberry Frozen Yogurt with White Chocolate Chips, Coconut, and Cherries.
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Blue haribo jelly beans. Raspberry flavour. Bought in the UK.
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A blue raspberry-flavoured Jolly Rancher Hard Candy Stix after being unwrapped in the Dulles section of Sterling, Loudoun County, Virginia.
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Chemical structure ofindigo dye,a widely produced blue dye.Blue jeansconsist of 1–3% by weight of thisorganic compound.
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Chemical structure of C.I. Acid Blue 9, a dye commonly used in candies.
Pigments for painting and glass
Bluepigmentswere once produced from minerals, especiallylapis lazuliand its close relativeultramarine.These minerals were crushed, ground into powder, and then mixed with a quick-drying binding agent, such as egg yolk (tempera painting); or with a slow-drying oil, such aslinseed oil,foroil painting.Two inorganic but synthetic blue pigments arecerulean blue(primarily cobalt(II) stanate:Co2SnO4) andPrussian blue(milori blue: primarilyFe7(CN)18). The chromophore in blueglassand glazes iscobalt(II). Diverse cobalt(II) salts such as cobalt carbonate or cobalt(II) aluminate are mixed with the silica prior to firing. The cobalt occupies sites otherwise filled with silicon.
Inks
Methyl blueis the dominant blue pigment in inks used in pens.[32]Blueprintinginvolves the production ofPrussian bluein situ.
Inorganic compounds
Certain metalionscharacteristically form blue solutions or blue salts. Of some practical importance,cobaltis used to make the deep blue glazes and glasses. It substitutes forsiliconoraluminumions in these materials. Cobalt is the bluechromophoreinstained glass windows,such as those inGothic cathedralsand in Chineseporcelainbeginning in theTang dynasty.Copper(II)(Cu2+) also produces many blue compounds, including the commercialalgicidecopper(II) sulfate(CuSO4.5H2O). Similarly,vanadylsalts and solutions are often blue, e.g.vanadyl sulfate.
In nature
Sky and sea
When sunlight passes through the atmosphere, the blue wavelengths are scattered more widely by the oxygen and nitrogen molecules, and more blue comes to our eyes. This effect is calledRayleigh scattering,afterLord Rayleighand confirmed byAlbert Einsteinin 1911.[33][34]
The sea is seen as blue for largely the same reason: the water absorbs the longer wavelengths of red and reflects and scatters the blue, which comes to the eye of the viewer. The deeper the observer goes, the darker the blue becomes. In the open sea, only about 1% of light penetrates to a depth of 200 metres (seeunderwaterandeuphotic depth).
The colour of the sea is also affected by the colour of the sky, reflected by particles in the water; and byalgaeand plant life in the water, which can make it look green; or by sediment, which can make it look brown.[35]
The farther away an object is, the more blue it often appears to the eye. For example, mountains in the distance often appear blue. This is the effect ofatmospheric perspective;the farther an object is away from the viewer, the less contrast there is between the object and its background colour, which is usually blue. In a painting where different parts of the composition are blue, green and red, the blue will appear to be more distant, and the red closer to the viewer. The cooler a colour is, the more distant it seems.[36]Blue light isscattered morethan other wavelengths by the gases in theatmosphere,hence our "blue planet".
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Earth's bluehalowhen seen from space
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Another example ofRayleigh scattering
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The sea
Minerals
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Naturalultramarinepigment
Some of the most desirable gems are blue, includingsapphireandtanzanite.Compounds of copper(II) are characteristically blue and so are many copper-containing minerals. Azurite(Cu3(CO3)2(OH)2),with a deep blue colour, was once employed in medieval years, but it is unstable pigment, losing its colour especially under dry conditions.Lapis lazuli,mined in Afghanistan for more than three thousand years, was used for jewelry and ornaments, and later was crushed and powdered and used as a pigment. The more it was ground, the lighter the blue colour became. Naturalultramarine,made by grinding lapis lazuli into a fine powder, was the finest available blue pigment in the Middle Ages and theRenaissance.It was extremely expensive, and inItalian Renaissanceart, it was often reserved for the robes of theVirgin Mary.
Plants and fungi
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Primula acaulis
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Morning glory (Ipomoea acuminata)
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Blue Delphinium flower
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Blue Lupme flowerLupinus pilosus
Intense efforts have focused on blue flowers and the possibility that natural blue colourants could be used as food dyes.[30]Commonly, blue colours in plants areanthocyanins:"the largest group of water-soluble pigments found widespread in the plant kingdom".[38]In the few plants that exploit structural colouration, brilliant colours are produced by structures within cells. The most brilliant blue colouration known in any living tissue is found in the marble berries ofPollia condensata,where a spiral structure of cellulose fibrils scattering blue light. The fruit ofquandong(Santalum acuminatum) can appear blue owing to the same effect.[30]
Animals
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Indigo buntingshave iridescent feathers.
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Blue facial ridges ofmandrill
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Themandarin fishis one of few animal species with blue pigment
Blue-pigmented animals are relatively rare.[39]Examples of which include butterflies of the genusNessaea,where blue is created bypterobilin.[40]Other blue pigments of animal origin include phorcabilin, used by other butterflies inGraphiumandPapilio(specificallyP. phorcasandP. weiskei), and sarpedobilin, which is used byGraphium sarpedon.[41]Blue-pigmentedorganelles,known as "cyanosomes", exist in thechromatophoresof at least two fish species, themandarin fishand thepicturesque dragonet.[42]More commonly, blueness in animals is astructural colouration;an optical interference effect induced by organized nanometre-sized scales or fibres. Examples include the plumage of several birds like theblue jayandindigo bunting,[43]the scales of butterflies like themorpho butterfly,[44]collagenfibres in the skin of some species of monkey andopossum,[45]and theiridophorecells in some fish and frogs.[46][47]
Eyes
Blue eyes do not actually contain any blue pigment.Eye colouris determined by two factors: thepigmentationof the eye'siris[48][49]and thescatteringof light by theturbidmedium in thestroma of the iris.[50]In humans, the pigmentation of the iris varies from light brown to black. The appearance of blue, green, and hazel eyes results from theTyndall scatteringof light in the stroma, an optical effect similar to what accounts for the blueness of the sky.[50][51]The irises of the eyes of people with blue eyes contain less darkmelaninthan those of people with brown eyes, which means that they absorb less short-wavelength blue light, which is instead reflected out to the viewer. Eye colour also varies depending on the lighting conditions, especially for lighter-coloured eyes.
Blue eyes are most common in Ireland, theBaltic Seaarea andNorthern Europe,[52]and are also found inEastern,Central,andSouthern Europe.Blue eyes are also found in parts ofWestern Asia,most notably inAfghanistan,Syria,Iraq,andIran.[53]InEstonia,99% of people have blue eyes.[54][55]InDenmarkin 1978, only 8% of the population had brown eyes, though through immigration, today that number is about 11%.[55]InGermany,about 75% have blue eyes.[55]
In the United States, as of 2006, 1 out of every 6 people, or 16.6% of the total population, and 22.3% of thewhite population,have blue eyes, compared with about half of Americans born in 1900, and a third of Americans born in 1950. Blue eyes are becoming less common among American children[citation needed].In the US, males are 3–5% more likely to have blue eyes than females.[52]
History
In the ancient world
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Lapis lazulibowl from Iran, end of 3rd – beginning of 2nd millennium BC (Louvre Museum)
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Egyptian bluetripodic beaker imitating lapis lazuli. South Mesopotamia. (1399-1200 BC)
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Fresco of Polyphemus and Galatea, Pompei, usingEgyptian blue(1st c. BC) (Metropolitan Museum)
As early as the7th millennium BC,lapis lazuli was mined in theSar-i Sangmines,[56]inShortugai,and in other mines inBadakhshanprovince in northeastAfghanistan.[57]
Lapis lazuli artifacts, dated to 7570 BC, have been found atBhirrana,which is the oldest site ofIndus Valley civilisation.[58]Lapis was highly valued by the Indus Valley Civilisation (7570–1900 BC).[58][59][60]Lapis beads have been found atNeolithicburials inMehrgarh,theCaucasus,and as far away asMauritania.[61]It was used in thefuneral mask of Tutankhamun(1341–1323 BC).[62]
A term for Blue was relatively rare in many forms of ancient art and decoration, and even in ancient literature. The Ancient Greek poets described the sea as green, brown or "the colour of wine". The colour is mentioned several times in theHebrew Bibleas 'tekhelet'. Reds, blacks, browns, and ochres are found incave paintingsfrom the UpperPaleolithicperiod, but not blue. Blue was also not used for dyeing fabric until long after red, ochre, pink, and purple. This is probably due to the perennial difficulty of making blue dyes and pigments. On the other hand, the rarity of blue pigment made it even more valuable.[63]
The earliest known blue dyes were made from plants –woadin Europe,indigoin Asia and Africa, while blue pigments were made from minerals, usually eitherlapis lazuliorazurite,and required more.[64]Blue glazes posed still another challenge since the early blue dyes and pigments were not thermally robust. Inc. 2500 BC,the blue glazeEgyptian bluewas introduced for ceramics, as well as many other objects.[65][66]The Greeks imported indigo dye from India, calling it indikon, and they painted with Egyptian blue. Blue was not one of the four primary colours for Greek painting described byPliny the Elder(red, yellow, black, and white). For the Romans, blue was the colour of mourning, as well as the colour of barbarians. The Celts and Germans reportedly dyed their faces blue to frighten their enemies, and tinted their hair blue when they grew old.[67]The Romans made extensive use of indigo and Egyptian blue pigment, as evidenced, in part, by frescos inPompeii. The Romans had many words for varieties of blue, includingcaeruleus,caesius,glaucus,cyaneus,lividus,venetus,aerius,andferreus,but two words, both of foreign origin, became the most enduring;blavus,from the Germanic wordblau,which eventually becamebleuor blue; andazureus,from the Arabic wordlazaward,which became azure.[68]
Blue was widely used in the decoration of churches in the Byzantine Empire.[69]By contrast, in the Islamic world, blue was of secondary to green, believed to be the favourite colour of theProphet Mohammed.At certain times inMoorish Spainand other parts of the Islamic world, blue was the colour worn by Christians and Jews, because only Muslims were allowed to wear white and green.[70]
In the Middle Ages
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Stained glass window atSaint Denis Basilica(1130–1140), coloured withcobalt blue
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Detail of the Blue Virgin Window,Chartres Cathedral(12th c.)
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TheWilton Diptych(1395–1399). TheVirgin Marywas traditionally shown in blue(14th c.)
In the art and life of Europe during the earlyMiddle Ages,blue played a minor role. This changed dramatically between 1130 and 1140 in Paris, when theAbbe Sugerrebuilt theSaint Denis Basilica.Suger considered that light was the visible manifestation of the Holy Spirit.[71]He installedstained glasswindows coloured withcobalt,which, combined with the light from the red glass, filled the church with a bluish violet light. The church became the marvel of theChristian world,and the colour became known as the"bleu de Saint-Denis".In the years that followed even more elegant blue stained glass windows were installed in other churches, including atChartres CathedralandSainte-Chapellein Paris.[72]
In the 12th century the Roman Catholic Church dictated that painters in Italy (and the rest of Europe consequently) to paint the Virgin Mary with blue, which became associated with holiness, humility and virtue. In medieval paintings, blue was used to attract the attention of the viewer to the Virgin Mary. Paintings of the mythicalKing Arthurbegan to show him dressed in blue. The coat of arms of the kings of France became an azure or light blue shield, sprinkled with goldenfleur-de-lisor lilies. Blue had come from obscurity to become the royal colour.[73]
Renaissance through 18th century
Blue came into wider use beginning in the Renaissance, when artists began to paint the world with perspective, depth, shadows, and light from a single source. In Renaissance paintings, artists tried to create harmonies between blue and red, lightening the blue with lead white paint and adding shadows and highlights.Raphaelwas a master of this technique, carefully balancing the reds and the blues so no one colour dominated the picture.[74]
Ultramarinewas the most prestigious blue of the Renaissance, being more expensive than gold. Wealthy art patrons commissioned works with the most expensive blues possible. In 1616Richard Sackvillecommissioned a portrait of himself byIsaac Oliverwith three different blues, including ultramarine pigment for his stockings.[75]
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Portrait of Richard Sackville (1616), using three expensive blues, including ultramarine for his stockings
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Ming dynasty,Porcelain vase painted with cobalt blue under transparent glaze. (15th c.) (Metropolitan Museum)
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Delftwareplaque with cobalt blue painting (1683) (Rijksmuseum, Amsterdam)
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Portrait of KingLouis XIV of Francein coronation robes, byHyacinthe Rigaud(c. 1700) (Louvre Museum)
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Urn byJosiah Wedgwood(1780s) (Metropolitan Museum)
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QueenMaria I of Portugal(late 1700s)
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"Girl with a Pearl Earring" byJohannes Vermeerfeaturesultramarinepigment
An industry for the manufacture of fine blue and white pottery began in the 14th century inJingdezhen,China, using white Chinese porcelain decorated with patterns ofcobalt blue,imported from Persia. It was first made for the family of the Emperor of China, then was exported around the world, with designs for export adapted to European subjects and tastes. The Chinese blue style was also adapted by Dutch craftsmen inDelftand English craftsmen inStaffordshirein the 17th-18th centuries. in the 18th century, blue and white porcelains were produced byJosiah Wedgwoodand other British craftsmen.[76]
19th-20th century
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Beau Brummel(1776–1840) introduced the ancestor of the modern blue suit
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QueenMaria II of Portugalin a blue andgold embroideredgown (1835)
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A California gold miner in blue jeans (1853)
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Isabel, Princess Imperial of Brazilin light blue gown (1853)
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New York City police in 1871
The early 19th century saw the ancestor of the modern blue business suit, created byBeau Brummel(1776–1840), who set fashion at the London Court. It also saw the invention ofblue jeans,a highly popular form of workers's costume, invented in 1853 byJacob W. Daviswho used metal rivets to strengthen bluedenimwork clothing in the California gold fields. The invention was funded by San Francisco entrepreneurLevi Strauss,and spread around the world.[77]
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Van Gogh'sStarry Night Over the Rhône(1888). Blue used to create a mood or atmosphere. A cobalt blue sky, and cobalt or ultramarine water.
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"The Conversation" byHenri Matisse(1908–1912)
Recognizing the emotional power of blue, many artists made it the central element of paintings in the 19th and 20th centuries. They includedPablo Picasso,Pavel Kuznetsovand theBlue Roseart group, andKandinskyandDer Blaue Reiter(The Blue Rider) school.[78]Henri Matisseexpressed deep emotions with blue, "A certain blue penetrates your soul."[79]In the second half of the 20th century, painters of theabstract expressionistmovement use blues to inspire ideas and emotions. PainterMark Rothkoobserved that colour was "only an instrument;" his interest was "in expressing human emotions tragedy, ecstasy, doom, and so on".[80]
In society and culture
Uniforms
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Navy bluederives its name from the uniform ofRoyal Navyofficers
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Ukrainian police officer in Donetsk
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Officers of theMilitary Police of Rio de Janeiro State,Brazil
In the 17th century. The Prince-Elector of Brandenburg,Frederick William I of Prussia,chosePrussian blueas the new colour of Prussian military uniforms, because it was made withWoad,a local crop, rather thanIndigo,which was produced by the colonies of Brandenburg's rival, England. It was worn by the German army until World War I, with the exception of the soldiers of Bavaria, who wore sky-blue.[81]
In 1748, theRoyal Navyadopted a dark shade of blue for the uniform of officers.[77]It was first known as marine blue, now known asnavy blue.[82]The militia organized byGeorge Washingtonselected blue andbuff,the colours of the BritishWhig Party.Blue continued to be the colour of the field uniform of the US Army until 1902, and is still the colour of the dress uniform.[83]
In the 19th century, police in the United Kingdom, including theMetropolitan Policeand theCity of London Policealso adopted a navy blue uniform. Similar traditions were embraced in France and Austria.[84]It was also adopted at about the same time for the uniforms of the officers of theNew York City Police Department.[77]
Gender
Blue is used to representmales.Beginning as a trend the mid-19th century and applying primarily to clothing, gendered associations with blue became more widespread from the 1950s. The colour became associated with males after thesecond world war.[85]
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This restroom sign on anAll Nippon AirwaysBoeing 767-300 uses pink for the female gender and blue for the male gender.
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Cake using blue to represent the male sex.
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Baby blue newborn male clothing
Religion
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Blue domes of the Church dedicated to St. Spirou in Firostefani,Santoriniisland (Thira), Greece.
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Persian blue inShah mosque(16th c.) inIsfahan,Iran
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The flag of Israel uses a special variety of blue, calledtekhelet
- Blue in Judaism:In theTorah,[86]theIsraeliteswere commanded to put fringes,tzitzit,on the corners of their garments, and to weave within these fringes a "twisted thread of blue (tekhelet) ".[87]In ancient days, this blue thread was made from a dye extracted from a Mediterranean snail called thehilazon.Maimonidesclaimed that this blue was the colour of "the clear noonday sky";Rashi,the colour of the evening sky.[88]According to several rabbinic sages, blue is the colour of God's Glory.[89]Staring at this colour aids in mediation, bringing us a glimpse of the "pavement of sapphire, like the very sky for purity", which is a likeness of the Throne of God.[90](TheHebrewword for glory) Many items in theMishkan,the portable sanctuary in the wilderness, such as themenorah,many of the vessels, and theArk of the Covenant,were covered with blue cloth when transported from place to place.[91]
- Blue inChristianity:Blue is particularly associated with theVirgin Mary.This was the result of a decree ofPope Gregory I(540–601) who ordered that all religious paintings should tell a story which was clearly comprehensible to all viewers, and that figures should be easily recognizable, especially that of the figure of Mary. If she was alone in the image, her costume was usually painted with the finest blue,ultramarine.If she was with Christ, her costume was usually painted with a less expensive pigment, to avoid outshining him.[92][93][94][95]
- Blue inHinduism:Many of the gods are depicted as having blue-coloured skin, particularly those associated withVishnu,who is said to be the preserver of the world, and thus intimately connected to water.KrishnaandRama,Vishnu's avatars, are usually depicted with blue skin.Shiva,the destroyer deity, is also depicted in a light-blue hue, and is calledNīlakaṇṭha,or blue-throated, for having swallowed poison to save the universe during theSamudra Manthana,the churning of the ocean of milk. Blue is used to symbolically represent the fifth, and the throat,chakra(Vishuddha).[96]
- Blue inSikhism:TheAkali Nihangswarriors wear all-blue attire.Guru Gobind Singhalso has ablue roanhorse.The Sikh Rehat Maryada states that theNishan Sahibhoisted outside everyGurudwarashould bexanthic(Basanti inPunjabi) or greyish blue (modern daynavy blue) (Surmaaee inPunjabi) colour.[97][98]
- Blue inPaganism:Blue is associated with peace, truth, wisdom, protection, and patience. It helps with healing, psychic ability, harmony, and understanding.[99]
Sports
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Serbian national volleyball team, 2012 Olympics
In sports, blue is widely represented in uniforms in part because the majority of national teams wear the colours of their national flag. For example, the national men's football team ofFranceare known asLes Bleus(the Blues). Similarly,Argentina,Italy,andUruguaywear blue shirts.[100]TheAsian Football Confederationand theOceania Football Confederationuse blue text on their logos. Blue is well represented inbaseball(Blue Jays),basketball,andAmerican football,andIce hockey.TheIndian national cricket teamwears blue uniform duringOne day internationalmatches, as such the team is also referred to as "Men in Blue".[101]
Politics
-
Flag of theUnited Nations,approximates "sky blue"
-
Flag of theEuropean Unionis "reflex blue", a medium dark blue
-
A presidential-election map of the US, 2008–2020. States that consistently vote for Democrats are termed "blue states".
Unlike red or green, blue was not strongly associated with any particular country, religion or political movement. As the colour of harmony, it was chosen as the colour for the flags of theUnited Nations,theEuropean Union,andNATO.[102]In politics, blue is often used as the colour of conservative parties, contrasting with the red associated with left-wing parties.[103]Some conservative parties that use the colour blue include theConservative Party (UK),[104]Conservative Party of Canada,[105]Liberal Party of Australia,[106]Liberal Party of Brazil,andLikudof Israel.[citation needed]However, in some countries, blue is not associated main conservative party. In the United States, the liberalDemocratic Partyis associated with blue, while the conservativeRepublican Partywith red. US states which have been won by the Democratic Party in four consecutive presidential elections are termed "blue states", while those that have been won by the Republican Party are termed "red states".[107]South Koreaalso uses this colour model, with theDemocratic Partyon the left using blue[108]and thePeople Power Partyon the right using red.
See also
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Works cited
- Ball, Philip (2001).Bright Earth, Art, and the Invention of Colour.London: Penguin Group. p. 507.ISBN978-2-7541-0503-3.(page numbers refer to the French translation)
- Bowersox, Gary W.; Chamberlin, Bonita E. (1995).Gemstones of Afghanistan.Tucson, AZ: Geoscience Press.
- Heller, Eva (2009).Psychologie de la couleur: effets et symboliques(in French). Munich: Pyramyd.ISBN978-2-35017-156-2.
- Pastoureau, Michel (2000).Bleu: Histoire d'une couleur(in French). Paris: Editions du Seuil.ISBN978-2-02-086991-1.
- Riley, Charles A. II (1995).Color Codes: Modern Theories of Color in Philosophy, Painting and Architecture, Literature, Music, and Psychology.Hanover, New Hampshire: University Press of New England.
- Travis, Tim (2020).The Victoria and Albert Museum Book of Colour in Design.Thames & Hudson.ISBN978-0-500-48027-4.
- Varichon, Anne (2005).Couleurs: pigments et teintures dans les mains des peuples(in French). Paris: Editions du Seuil.ISBN978-2-02-084697-4.
- Lours, Mathieu (2020).Le Vitrai.Éditions Jean-Paul Gisserot.ISBN978-2-755-80845-2.
Further reading
- Balfour-Paul, Jenny (1998).Indigo.London: British Museum Press.ISBN978-0-7141-1776-8.
- Josserand, M.; Meeussen, E.; Majid, A. (27 September 2021)."Environment and culture shape both the colour lexicon and the genetics of colour perception".Sci Rep.11(19095). Nature: 19095.Bibcode:2021NatSR..1119095J.doi:10.1038/s41598-021-98550-3.PMC8476573.PMID34580373.S2CID238202924.
- Macdonald, Fiona (7 April 2018)."There's Evidence Humans Didn't Actually See Blue Until Modern Times".Science Alert.Archived fromthe originalon 24 June 2022.Retrieved24 June2022.
- Mollo, John (1991).Uniforms of The American Revolution in Color.Illustrated byMalcolm McGregor.New York:Stirling Publications.ISBN978-0-8069-8240-3.
External links
- The dictionary definition ofblueat Wiktionary
- Media related toblueat Wikimedia Commons
- "Friday essay: from the Great Wave to Starry Night, how a blue pigment changed the world", By Hugh Davies, theconversation