Type a search term to find related articles by LIMS subject matter experts gathered from the most trusted and dynamic collaboration tools in the laboratory informatics industry.
Purple | |
---|---|
Color coordinates | |
Hex triplet | #800080 |
sRGBB (r, g, b) | (128, 0, 128) |
HSV (h, s, v) | (300°, 100%, 50%) |
CIELChuv (L, C, h) | (30, 68, 308°) |
Source | HTML color names |
B: Normalized to [0–255] (byte) H: Normalized to [0–100] (hundred) |
Purple is a color similar in appearance to violet light. In the RYB color model historically used in the arts, purple is a secondary color created by combining red and blue pigments. In the CMYK color model used in modern printing, purple is made by combining magenta pigment with either cyan pigment, black pigment, or both. In the RGB color model used in computer and television screens, purple is created by mixing red and blue light in order to create colors that appear similar to violet light.
Purple has long been associated with royalty, originally because Tyrian purple dye—made from the secretions of sea snails—was extremely expensive in antiquity.[1] Purple was the color worn by Roman magistrates; it became the imperial color worn by the rulers of the Byzantine Empire and the Holy Roman Empire, and later by Roman Catholic bishops. Similarly in Japan, the color is traditionally associated with the emperor and aristocracy.[2]
According to contemporary surveys in Europe and the United States, purple is the color most often associated with rarity, royalty, luxury, ambition, magic, mystery, piety and spirituality.[3][4] When combined with pink, it is associated with eroticism, femininity, and seduction.[5]
The modern English word purple comes from the Old English purpul, which derives from Latin purpura, which, in turn, derives from the Greek πορφύρα (porphura),[6] the name of the Tyrian purple dye manufactured in classical antiquity from a mucus secreted by the spiny dye-murex snail.[7][8] The first recorded use of the word purple dates to the late 900s AD.[7]
Purple first appeared in prehistoric art during the Neolithic era. The artists of Pech Merle cave and other Neolithic sites in France used sticks of manganese and hematite powder to draw and paint animals and the outlines of their own hands on the walls of their caves. These works have been dated to between 16,000 and 25,000 BC.[9]
Purple textiles, dating back to the early second millennium BCE, were found in Syria, making them the oldest known purple textiles in the world. These findings include textiles from a burial site in Chagar Bazar, dating back to the 18th-16th centuries BCE, as well as preserved textile samples discovered in gypsum at the Royal Palace of Qatna.[10][11][12]
As early as the 15th century BC, the citizens of Sidon and Tyre, two cities on the coast of Ancient Phoenicia (present day Lebanon), were producing purple dye from a sea snail called the spiny dye-murex.[13] Clothing colored with the Tyrian dye was mentioned in both the Iliad of Homer and the Aeneid of Virgil.[13] The deep, rich purple dye made from this snail became known as Tyrian purple.[14]
The process of making the dye was long, difficult and expensive. Thousands of the tiny snails had to be found, their shells cracked, the snail removed. Mountains of empty shells have been found at the ancient sites of Sidon and Tyre. The snails were left to soak, then a tiny gland was removed and the juice extracted and put in a basin, which was placed in the sunlight. There, a remarkable transformation took place. In the sunlight the juice turned white, then yellow-green, then green, then violet, then a red which turned darker and darker. The process had to be stopped at exactly the right time to obtain the desired color, which could range from a bright crimson to a dark purple, the color of dried blood. Then either wool, linen or silk would be dyed. The exact hue varied between crimson and violet, but it was always rich, bright and lasting.[15]
Tyrian purple became the color of kings, nobles, priests and magistrates all around the Mediterranean. It was mentioned in the Hebrew Bible (Old Testament); in the Book of Exodus, God instructs Moses to have the Israelites bring him an offering including cloth "of blue, and purple, and scarlet,"[16] to be used in the curtains of the Tabernacle and the garments of priests. The term used for purple in the 4th-century Latin Vulgate version of the Bible passage is purpura or Tyrian purple.[17] In the Iliad of Homer, the belt of Ajax is purple, and the tails of the horses of Trojan warriors are dipped in purple. In the Odyssey, the blankets on the wedding bed of Odysseus are purple. In the poems of Sappho (6th century BC) she celebrates the skill of the dyers of the Greek kingdom of Lydia who made purple footwear, and in the play of Aeschylus (525–456 BC), Queen Clytemnestra welcomes back her husband Agamemnon by decorating the palace with purple carpets. In 950 BC, King Solomon was reported to have brought artisans from Tyre to provide purple fabrics to decorate the Temple of Jerusalem.[18]
Alexander the Great (when giving imperial audiences as the basileus of the Macedonian Empire), the basileus of the Seleucid Empire, and the kings of Ptolemaic Egypt all wore Tyrian purple.
The Roman custom of wearing purple togas may have come from the Etruscans; an Etruscan tomb painting from the 4th century BC shows a nobleman wearing a deep purple and embroidered toga.
In Ancient Rome, the Toga praetexta was an ordinary white toga with a broad purple stripe on its border. It was worn by freeborn Roman boys who had not yet come of age,[19] curule magistrates,[20][21] certain categories of priests,[22] and a few other categories of citizens.
The Toga picta was solid purple, embroidered with gold. During the Roman Republic, it was worn by generals in their triumphs, and by the Praetor Urbanus when he rode in the chariot of the gods into the circus at the Ludi Apollinares.[23] During the Empire, the toga picta was worn by magistrates giving public gladiatorial games, and by the consuls, as well as by the emperor on special occasions.
During the Roman Republic, when a triumph was held, the general being honored wore an entirely purple toga bordered in gold, and Roman Senators wore a toga with a purple stripe. However, during the Roman Empire, purple was more and more associated exclusively with the emperors and their officers.[24] Suetonius claims that the early emperor Caligula had the King of Mauretania murdered for the splendour of his purple cloak, and that Nero forbade the use of certain purple dyes.[25] In the late empire the sale of purple cloth became a state monopoly protected by the death penalty.[26]
According to the New Testament, Jesus Christ, in the hours leading up to his crucifixion, was dressed in purple (πορφύρα: porphura) by the Roman garrison to mock his claim to be 'King of the Jews'.[27]
The actual color of Tyrian purple seems to have varied from a reddish to a bluish purple. According to the Roman writer Vitruvius, (1st century BC), the murex shells coming from northern waters, probably Bolinus brandaris, produced a more bluish color than those of the south, probably Hexaplex trunculus. The most valued shades were said to be those closer to the color of dried blood, as seen in the mosaics of the robes of the Emperor Justinian in Ravenna. The chemical composition of the dye from the murex is close to that of the dye from indigo, and indigo was sometimes used to make a counterfeit Tyrian purple, a crime which was severely punished. What seems to have mattered about Tyrian purple was not its color, but its luster, richness, its resistance to weather and light, and its high price.[28]
In modern times, Tyrian purple has been recreated, at great expense. When the German chemist Paul Friedander tried to recreate Tyrian purple in 2008, he needed twelve thousand mollusks to create 1.4 ounces of dye, enough to color a handkerchief. In the year 2000, a gram of Tyrian purple made from ten thousand mollusks according to the original formula cost two thousand euros.[29][30]
In ancient China, purple was obtained not through the Mediterranean mollusc, but purple gromwell. The dye obtained did not easily adhere to fabrics, making purple fabrics expensive. Purple became a fashionable color in the state of Qi (齊, 1046 BC–221 BC) because its ruler, Duke Huan of Qi, developed a preference for it. As a result, the price of purple fabric was over five times that of plain fabric. His minister, Guan Zhong (管仲), eventually convinced him to relinquish this preference.
China was the first culture to develop a synthetic purple color.[31]
An old hypothesis suggested links between the Chinese purple and blue and Egyptian blue, however, molecular structure analysis and evidence such as the absence of lead in Egyptian blue and the lack of examples of Egyptian blue in China, argued against the hypothesis.[32][33] The use of quartz, barium, and lead components in ancient Chinese glass and Han purple and Han blue has been used to suggest a connection between glassmaking and the manufacture of pigments,[34] and to prove the independence of the Chinese invention.[32] Taoist alchemists may have developed Han purple from their knowledge of glassmaking.[32]
Lead is used by the pigment maker to lower the melting point of the barium in Han Purple.[35]
Purple was regarded as a secondary color in ancient China. In classical times, secondary colors were not as highly prized as the five primary colors of the Chinese spectrum, and purple was used to allude to impropriety, in contrast to crimson, which was deemed a primary color and symbolized legitimacy. Nevertheless, by the 6th century AD, purple was ranked above crimson. Several changes to the ranks of colors occurred after that time.
Through the early Christian era, the rulers of the Byzantine Empire continued the use of purple as the imperial color, for diplomatic gifts, and even for imperial documents and the pages of the Bible. Gospel manuscripts were written in gold lettering on parchment that was colored Tyrian purple.[36] Empresses gave birth in the Purple Chamber, and the emperors born there were known as "born to the purple," to separate them from emperors who won or seized the title through political intrigue or military force. Bishops of the Byzantine church wore white robes with stripes of purple, while government officials wore squares of purple fabric to show their rank.
In western Europe, the Emperor Charlemagne was crowned in 800 wearing a mantle of Tyrian purple, and was buried in 814 in a shroud of the same color, which still exists (see below). However, after the fall of Constantinople to the Ottoman Turks in 1453, the color lost its imperial status. The great dye works of Constantinople were destroyed, and gradually scarlet, made with dye from the cochineal insect, became the royal color in Europe.[37]
In 1464, Pope Paul II decreed that cardinals should no longer wear Tyrian purple, and instead wear scarlet, from kermes and alum,[38] since the dye from Byzantium was no longer available. Bishops and archbishops, of a lower status than cardinals, were assigned the color purple, but not the rich Tyrian purple. They wore cloth dyed first with the less expensive indigo blue, then overlaid with red made from kermes dye.[39][40]
While purple was worn less frequently by Medieval and Renaissance kings and princes, it was worn by the professors of many of Europe's new universities. Their robes were modeled after those of the clergy, and they often wore square/violet or purple/violet caps and robes, or black robes with purple/violet trim. Purple/violet robes were particularly worn by students of divinity.
Purple and violet also played an important part in the religious paintings of the Renaissance. Angels and the Virgin Mary were often portrayed wearing purple or violet robes.
In the 18th century, purple was still worn on occasion by Catherine the Great and other rulers, by bishops and, in lighter shades, by members of the aristocracy, but rarely by ordinary people, because of its high cost. But in the 19th century, that changed.
In 1856, an eighteen-year-old British chemistry student named William Henry Perkin was trying to make a synthetic quinine. His experiments produced instead the first synthetic aniline dye, a purple shade called mauveine, shortened simply to mauve. It took its name from the mallow flower, which is the same color.[41] The new color quickly became fashionable, particularly after Queen Victoria wore a silk gown dyed with mauveine to the Royal Exhibition of 1862. Prior to Perkin's discovery, mauve was a color which only the aristocracy and rich could afford to wear. Perkin developed an industrial process, built a factory, and produced the dye by the ton, so almost anyone could wear mauve. It was the first of a series of modern industrial dyes which completely transformed both the chemical industry and fashion.[42]
Purple was popular with the pre-Raphaelite painters in Britain, including Arthur Hughes, who loved bright colors and romantic scenes.
At the turn of the century, purple was a favorite color of the Austrian painter Gustav Klimt, who flooded his pictures with sensual purples and violets.
In the 20th century, purple retained its historic connection with royalty; George VI (1896–1952), wore purple in his official portrait, and it was prominent in every feature of the coronation of Elizabeth II in 1953, from the invitations to the stage design inside Westminster Abbey. But at the same time, it was becoming associated with social change; with the Women's Suffrage movement for the right to vote for women in the early decades of the century, with Feminism in the 1970s, and with the psychedelic drug culture of the 1960s.
In the early 20th century, purple, green, and white were the colors of the Women's Suffrage movement, which fought to win the right to vote for women, finally succeeding with the 19th Amendment to the U.S. Constitution in 1920. Later, in the 1970s, in a tribute to the Suffragettes, it became the color of the women's liberation movement.[43]
In the concentration camps of Nazi Germany, prisoners who were members of non-conformist religious groups, such as the Jehovah's Witnesses, were required to wear a purple triangle.[44]
During the 1960s and early 1970s, it was also associated with counterculture, psychedelics, and musicians like Jimi Hendrix with his 1967 song "Purple Haze", or the English rock band of Deep Purple which formed in 1968. Later, in the 1980s, it was featured in the song and album Purple Rain (1984) by the American musician Prince.
The Purple Rain Protest was a protest against apartheid that took place in Cape Town, South Africa on 2 September 1989, in which a police water cannon with purple dye sprayed thousands of demonstrators. This led to the slogan The Purple Shall Govern.
The violet or purple necktie became very popular at the end of the first decade of the 21st century, particularly among political and business leaders. It combined the assertiveness and confidence of a red necktie with the sense of peace and cooperation of a blue necktie, and it went well with the blue business suit worn by most national and corporate leaders.[45]
The meanings of the color terms violet and purple varies even among native speakers of English, for example between United Kingdom and United States.[46] Optics research on purple and violet contains contributions of authors from different countries and different native languages, it is likely to be inconsistent in the use and meaning of the two colors.
According to some speakers/authors of English, purple, unlike violet, is not one of the colors of the visible spectrum.[47] It was not one of the colors of the rainbow identified by Isaac Newton. According to some authors, purple does not have its own wavelength of light. For this reason, it is sometimes called a non-spectral color. It exists in culture and art, but not, in the same way that violet does, in optics. According to some speakers of English, purple is simply a combination, in various proportions, of two primary colors, red and blue.[48] According to other speakers of English, the same range of colors is called violet.[49]
In some textbooks of color theory, and depending on the geographical-cultural origin of the author, a "purple" is defined as any non-spectral color between violet and red (excluding violet and red themselves).[50] In that case, the spectral colors violet and indigo would not be shades of purple. For other speakers of English, these colors are shades of purple.
In the traditional color wheel long used by painters, purple is placed between crimson and violet.[51] However, also here there is much variation in color terminology depending on cultural background of the painters and authors, and sometimes the term violet is used and placed in between red and blue on the traditional color wheel. In a slightly different variation, on the color wheel, purple is placed between magenta and violet. This shade is sometimes called electric purple (see shades of purple).[52]
In the RGB color model, named for the colors red, green, and blue, used to create all the colors on a computer screen or television, the range of purples is created by mixing red and blue light of different intensities on a black screen. The standard HTML color purple is created by red and blue light of equal intensity, at a brightness that is halfway between full power and darkness.
In color printing, purple is sometimes represented by the color magenta, or sometimes by mixing magenta with red or blue. It can also be created by mixing just red and blue alone, but in that case the purple is less bright, with lower saturation or intensity. A less bright purple can also be created with light or paint by adding a certain quantity of the third primary color (green for light or yellow for pigment).
Purple is closely associated with violet. In common usage, both refer to a variety of colors between blue and red in hue.[53][54][55] Historically, purple has tended to be used for redder hues and violet for bluer hues.[53][56][57] In optics, violet is a spectral color; it refers to the color of any different single wavelength of light on the short wavelength end of the visible spectrum, between approximately 380 and 450 nanometers,[58] whereas purple is the color of various combinations of red, blue, and violet light,[50][55] some of which humans perceive as similar to violet.
On a chromaticity diagram, the straight line connecting the extreme spectral colors (red and violet) is known as the line of purples (or 'purple boundary'); it represents one limit of human color perception. The color magenta used in the CMYK printing process is near the center of the line of purples, but most people associate the term "purple" with a somewhat bluer tone, such as is displayed by the color "electric purple" (a color also directly on the line of purples), shown below.
On the CIE xy chromaticity diagram, violet is on the curved edge in the lower left, while purples are on the straight line connecting the extreme colors red and violet; this line is known as the line of purples, or the purple line.[59][60]
During the Middle Ages, artists usually made purple by combining red and blue pigments; most often blue azurite or lapis-lazuli with red ochre, cinnabar, or minium. They also combined lake colors made by mixing dye with powder; using woad or indigo dye for the blue, and dye made from cochineal for the red.[64]
The most famous purple dye in the ancient world was Tyrian purple, made from a type of sea snail called the murex, found around the Mediterranean. (See history section above).[47]
In western Polynesia, residents of the islands made a purple dye similar to Tyrian purple from the sea urchin. In Central America, the inhabitants made a dye from a different sea snail, the purpura, found on the coasts of Costa Rica and Nicaragua. The Mayans used this color to dye fabric for religious ceremonies, while the Aztecs used it for paintings of ideograms, where it symbolized royalty.[64]
In the Middle Ages, those who worked with blue and black dyes belonged to separate guilds from those who worked with red and yellow dyes, and were often forbidden to dye any other colors than those of their own guild.[66] Most purple fabric was made by the dyers who worked with red, and who used dye from madder or cochineal, so Medieval violet colors were inclined toward red.[67]
Orcein, or purple moss, was another common purple dye. It was known to the ancient Greeks and Hebrews, and was made from a Mediterranean lichen called archil or dyer's moss (Roccella tinctoria), combined with an ammoniac, usually urine. Orcein began to achieve popularity again in the 19th century, when violet and purple became the color of demi-mourning, worn after a widow or widower had worn black for a certain time, before he or she returned to wearing ordinary colors.[68]
From the Middle Ages onward, purple dyes for the clothing of common people were often made from the blackberry or other red fruit of the genus rubus, or from the mulberry. All of these dyes were more reddish than bluish, and faded easily with washing and exposure to sunlight.
A popular new dye which arrived in Europe from the New World during the Renaissance was made from the wood of the logwood tree (Haematoxylum campechianum), which grew in Spanish Mexico. Depending on the different minerals added to the dye, it produced a blue, red, black or, with the addition of alum, a purple color, it made a good color, but, like earlier dyes, it did not resist sunlight or washing.
In the 18th century, chemists in England, France and Germany began to create the first synthetic dyes. Two synthetic purple dyes were invented at about the same time. Cudbear is a dye extracted from orchil lichens that can be used to dye wool and silk, without the use of mordant. Cudbear was developed by Dr Cuthbert Gordon of Scotland: production began in 1758, The lichen is first boiled in a solution of ammonium carbonate. The mixture is then cooled and ammonia is added and the mixture is kept damp for 3–4 weeks. Then the lichen is dried and ground to powder. The manufacture details were carefully protected, with a ten-feet high wall being built around the manufacturing facility, and staff consisting of Highlanders sworn to secrecy.
French purple was developed in France at about the same time. The lichen is extracted by urine or ammonia. Then the extract is acidified, the dissolved dye precipitates and is washed. Then it is dissolved in ammonia again, the solution is heated in air until it becomes purple, then it is precipitated with calcium chloride; the resulting dye was more solid and stable than other purples.
Cobalt violet is a synthetic pigment that was invented in the second half of the 19th century, and is made by a similar process as cobalt blue, cerulean blue and cobalt green. It is the violet pigment most commonly used today by artists. In spite of its name, this pigment produces a purple rather than violet color [46]
Mauveine, also known as aniline purple and Perkin's mauve, was the first synthetic organic chemical dye,[69][70] discovered serendipitously in 1856.
Its chemical name is 3-amino-2,±9-dimethyl-5-phenyl-7-(p-tolylamino)phenazinium acetate.
Fuchsine was another synthetic dye made shortly after mauveine. It produced a brilliant fuchsia color.
In the 1950s, a new family of purple and violet synthetic organic pigments called quinacridone came onto the market. It had originally been discovered in 1896, but were not synthesized until 1936, and not manufactured until the 1950s. The colors in the group range from deep red to bluish purple in color, and have the molecular formula C20H12N2O2. They have strong resistance to sunlight and washing, and are widely used today in oil paints, water colors, and acrylics, as well as in automobile coatings and other industrial coatings.
Certain grapes, eggplants, pansies and other fruits, vegetables and flowers may appear purple due to the presence of natural pigments called anthocyanins. These pigments are found in the leaves, roots, stems, vegetables, fruits and flowers of all plants. They aid photosynthesis by blocking harmful wavelengths of light that would damage the leaves. In flowers, the purple anthocyanins help attract insects who pollinate the flowers. Not all anthocyanins are purple; they vary in color from red to purple to blue, green, or yellow, depending upon the level of their pH.
It has been observed that the greater the distance between a viewers eyes and mountains, the lighter and more blue or purple they will appear. This phenomenon, long recognized by Leonardo da Vinci and other painters, is called aerial perspective or atmospheric perspective. The more distant the mountains are, the less contrast the eye sees between the mountains and the sky.
The bluish color is caused by an optical effect called Rayleigh scattering. The sunlit sky is blue because air scatters short-wavelength light more than longer wavelengths. Since blue light is at the short wavelength end of the visible spectrum, it is more strongly scattered in the atmosphere than long wavelength red light. The result is that the human eye perceives blue when looking toward parts of the sky other than the sun.[74]
At sunrise and sunset, the light is passing through the atmosphere at a lower angle, and traveling a greater distance through a larger volume of air. Much of the green and blue is scattered away, and more red light comes to the eye, creating the colors of the sunrise and sunset and making the mountains look purple.
The phenomenon is referenced in the song "America the Beautiful", where the lyrics refer to "purple mountains' majesty" among other features of the United States landscape. A Crayola crayon called Purple Mountain Majesty in reference to the lyric was first formulated in 1993.
Julius Pollux, a Greek grammarian who lived in the second century AD, attributed the discovery of purple to the Phoenician god and guardian of the city of Tyre, Heracles.[75] According to his account, while walking along the shore with the nymph Tyrus, the god's dog bit into a murex shell, causing his mouth to turn purple. The nymph subsequently requested that Heracles create a garment for her of that same color, with Heracles obliging her demands giving birth to Tyrian purple.[75][41]
In Europe, since some Roman emperors wore a Tyrian purple (purpura) toga praetexta, purple has been the color most associated with power and royalty.[47] The British Royal Family and other European royalty still use it as a ceremonial color on special occasions.[76] In Japan, purple is associated with the emperor and Japanese aristocracy.[2]
In the West, purple or violet is a color often associated with piety and religious faith.[76][77] In AD 1464, shortly after the Muslim conquest of Constantinople, which terminated the supply of Tyrian purple to Roman Catholic Europe, Pope Paul II decreed that cardinals should henceforth wear scarlet instead of purple, the scarlet being dyed with expensive cochineal.[citation needed] Bishops were assigned the color amaranth, being a pale and pinkish purple made then from a less-expensive mixture of indigo and cochineal.
In the Latin liturgical rites of the Catholic liturgy, purple represents penitence; Anglican and Catholic priests wear a purple stole when they hear confession and a purple stole and chasuble during Advent and Lent. Since the Second Vatican Council of 1962–5, priests may wear purple vestments, but may still wear black ones, when officiating at funerals. The Roman Missal permits black, purple (violet), or white vestments for the funeral Mass. White is worn when a child dies before the age of reason. Students and faculty of theology also wear purple academic dress for graduations and other university ceremonies.[citation needed]
Purple is also often worn by senior pastors of Protestant churches and bishops of the Anglican Communion.
The color purple is also associated with royalty in Christianity, being one of the three traditional offices of Jesus Christ, i. e. king, although such a symbolism was assumed from the earlier Roman association or at least also employed by the ancient Romans.
In Europe and America, purple is the color most associated with vanity, extravagance, and individualism. Among the seven deadly sins, it represents pride. It is a color which is used to attract attention.[78]
Purple is the color most often associated with the artificial and the unconventional. It is the major color that occurs the least frequently in nature, and was the first color to be synthesized.[79]
Purple is the color most associated with ambiguity. Like other colors made by combining two primary colors, it is seen as uncertain and equivocal.[80]
In Britain, purple is sometimes associated with mourning. In Victorian times, close relatives wore black for the first year following a death ("deep mourning"), and then replaced it with purple or dark green trimmed with black. This is rarely practised today.[81]
Purple represented the height of Roman virtue and cultural values.[77]
The color purple plays a significant role in the traditions of engineering schools across Canada.[83] Purple is also the color of the Engineering Corp in the British Military.[84]
"Roses are red, violets are purple
Sugar is sweet and so is maple surple"
Purple is sometimes associated with the lesbian, gay, bisexual, and transgender (LGBT) community.[93] It is the symbolic color worn on Spirit Day, a commemoration that began in 2010 to show support for young people who are bullied because of their sexual orientation.[94][95] Purple is closely associated with bisexuality, largely in part to the bisexual pride flag which combines pink – representing homosexuality – and blue – representing heterosexuality – to create the bisexual purple.[96][97] The purple hand is another symbol sometimes used by the LGBT community during parades and demonstrations.
The British chocolate company Cadbury chose purple as it was Queen Victoria's favourite color.[99] The company trademarked the color purple for chocolates with registrations in 1995[100] and 2004.[101] However, the validity of these trademarks is the matter of an ongoing legal dispute following objections by Nestlé.[102]
a confusing drug-induced state