Violet is the color at the end of the visible spectrum of light between blue and the invisible ultraviolet. Violet color has a dominant wavelength of approximately 380-450 nanometers. Light with a shorter wavelength than violet but longer than X-rays and gamma rays is called ultraviolet. In the color wheel historically used by painters, it is located between blue and purple. On the screens of computer monitors and television sets, a color which looks similar to violet is made, with the RGB color model, by mixing red and blue light, with the blue twice as bright as the red. This is not true violet, for it does not match the color of a single wavelength shorter than that of blue light.
The color's name is derived from the violet flower. Violet and purple look similar, but violet is a spectral color, with its own set of wavelengths on the spectrum of visible light. Purple is a dichromatic color, made by combining blue and red. Amethyst is a notable violet crystal, its colour arising from iron and other trace elements in quartz.
In history, violet and purple have long been associated with royalty and majesty. The emperors of Rome wore purple togas, as did the Byzantine emperors. During the Middle Ages violet was worn by bishops and university professors and was often used in art as the color of the robes of the Virgin Mary. In Chinese painting, the color violet represents the harmony of the universe because it is a combination of red and blue (Yin and yang respectively). In Hinduism and Buddhism violet is associated with the Crown Chakra. According to surveys in Europe and the United States, violet is the color people most often associate with extravagance and individualism, the unconventional, the artificial, and ambiguity.
|sRGBB (r, g, b)||(127, 0, 255)|
|CMYKH (c, m, y, k)||(50, 100, 0, 0)|
|HSV (h, s, v)||(270°, 100%, 100%)|
|B: Normalized to [0–255] (byte)|
H: Normalized to [0–100] (hundred)
|Violet as a tertiary color|
From the Middle English and old French violette, and from the Latin viola, the names of the violet flower. The first recorded use of violet as a color name in English was in 1370. Violet can also refer to the first violas which were originally painted a similar color.
In the traditional color wheel used by painters, violet and purple are both placed between red and blue. Purple occupies the space closer to red, between crimson and violet. Violet is closer to blue, and usually less intense and bright than purple.
From the point of view of optics, violet is a real color: it occupies its own place at the end of the visible spectrum, and was one of the seven spectral colors of the spectrum first described by Isaac Newton in 1672.
In the additive color system, used to create colors on a computer screen or on a color television, violet is simulated by purple, by combining blue light at high intensity with a less intense red light on a black screen. The range of purples is created by combining blue and red light of any intensities; the chromaticities formed this way line along the "line of purples".
Violet is one of the oldest colors used by man. Traces of very dark violet, made by grinding the mineral manganese, mixed with water or animal fat and then brushed on the cave wall or applied with the fingers, are found in the prehistoric cave art in Pech Merle, in France, dating back about twenty-five thousand years. It has also been found in the cave of Altamira and Lascaux. It was sometimes used as an alternative to black charcoal. Sticks of manganese, used for drawing, have been found at sites occupied by Neanderthal man in France and Israel. From the grinding tools at various sites, it appears it may also have been used to color the body and to decorate animal skins.
More recently, the earliest dates on cave paintings have been pushed back farther than 35,000 years. Hand paintings on rock walls in Australia may be even older, dating back as far as 50,000 years.
Berries of the genus rubus, such as blackberries, were a common source of dyes in antiquity. The ancient Egyptians made a kind of violet dye by combining the juice of the mulberry with crushed green grapes. The Roman historian Pliny the Elder reported that the Gauls used a violet dye made from bilberry to color the clothing of slaves. These dyes made a satisfactory purple, but it faded quickly in sunlight and when washed.
Violet and purple retained their status as the color of emperors and princes of the church throughout the long rule of the Byzantine Empire.
While violet 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 caps and violet robes, or black robes with violet trim.
Violet also played an important part in the religious paintings of the Renaissance. Angels and the Virgin Mary were often portrayed wearing violet robes. The 15th-century Florentine painter Cennino Cennini advised artists: "If you want to make a lovely violet colour, take fine lacca, ultramarine blue (the same amount of the one as of the other)..." For fresco painters, he advised a less-expensive version, made of a mixture of blue indigo and red hematite.
In the 18th century, violet was a color worn by royalty, aristocrats and the wealthy, and by both men and women. Good-quality violet fabric was expensive, and beyond the reach of ordinary people.
Many painters of the 19th century experimented with the uses of the color violet to capture the subtle effects of light. Eugène Delacroix (1798–1863) made use of violet in the sky and shadows of many of his works, such as his painting of a tiger.
The first cobalt violet, the intensely red-violet cobalt arsenate, was highly toxic. Although it persisted in some paint lines into the twentieth-century, it was displaced by less toxic cobalt compounds such as cobalt phosphate. Cobalt violet appeared in the second half of the 19th century, broadening the palette of artists. Cobalt violet was used by Paul Signac (1863–1935), Claude Monet (1840–1926), and Georges Seurat (1859–1891). Today, cobalt ammonium phosphate, cobalt lithium phosphate, and cobalt phosphate are available for use by artists. Cobalt ammonium phosphate is the most reddish of the three. Cobalt phosphate is available in two varieties — a deep less saturated blueish type and a lighter and brighter somewhat more reddish type. Cobalt lithium phosphate is a saturated lighter-valued bluish violet. A color similar to cobalt ammonium phosphate, cobalt magnesium borate, was introduced in the later twentieth-century but was not deemed sufficiently lightfast for artistic use. Cobalt violet is the only truly lightfast violet pigment with relatively strong color saturation. All other light-stable violet pigments are dull by comparison. However, the high price of the pigment and the toxicity of cobalt has limited its use.
Vincent van Gogh (1853–1890) was an avid student of color theory. He used violet in many of his paintings of the 1880s, including his paintings of irises and the swirling and mysterious skies of his starry night paintings, and often combined it with it complementary color, yellow. In his painting of his bedroom in Arles (1888), he used several sets of complementary colors; violet and yellow, red and green, and orange and blue. In a letter about the painting to his brother Theo, he wrote, "The color here...should be suggestive of sleep and repose in general....The walls are a pale violet. The floor is of red tiles. The wood of the bed and the chairs are fresh butter yellow, the sheet and the pillows light lemon green. The bedspread bright scarlet. The window green. The bed table orange. The bowl blue. The doors lilac....The painting should rest the head or the imagination."
In 1856, a young British chemist named William Henry Perkin was trying to make a synthetic quinine. His experiments produced instead an unexpected residue, which turned out to be the first synthetic aniline dye, a deep violet color called mauveine, or abbreviated simply to mauve (the dye being named after the lighter color of the mallow [mauve] flower). Used to dye clothes, it became extremely fashionable among the nobility and upper classes in Europe, 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.
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.
Violet is at one end of the spectrum of visible light, between blue and the invisible ultraviolet. It has the shortest wavelength of all the visible colors. It is the color the eye sees looking at light with a wavelength of between 380 and 450 nanometers.
In the traditional color wheel used by painters, violet and purple lie between red and blue. Violet is inclined toward blue, while purple is inclined toward red.
Violet colors composed by mixing blue and red light are within the purple colors (the word "purple" is used in the common sense for any color between blue and red). In color theory, a purple is a color along the line of purples on the CIE chromaticity diagram and excludes violet. Violet light from the rainbow, which can be referred as spectral violet, has only short wavelengths.
Violet objects are objects that reflect violet light. Objects reflecting spectral violet often appear dark, because human vision is relatively insensitive to those wavelengths. Monochromatic lamps emitting spectral-violet wavelengths can be roughly approximated by the color shown below as electric violet.
The earliest violet pigments used by humans, found in prehistoric cave paintings, were made from the minerals manganese and hematite. Manganese is still used today by the Aranda people, a group of indigenous Australians, as a traditional pigment for coloring the skin during rituals. It is also used by the Hopi Indians of Arizona to color ritual objects.
In western Polynesia, residents of the islands made a violet 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, and the Aztecs used it for paintings of ideograms, where it symbolized royalty.
During the Middle Ages, most artists made purple or violet on their paintings by combining red and blue pigments; usually 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.
Orcein, or purple moss, was another common violet dye. It was known to the ancient Greeks and Hebrews, 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.
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, along with manganese violet.
Mauveine, also known as aniline purple and Perkin's mauve, was the first synthetic organic chemical dye, discovered serendipitously in 1856. Its chemical name is 3-amino-2,±9-dimethyl-5-phenyl-7-(p-tolylamino) phenazinium acetate.
In the 1950s, a new family of violet synthetic organic pigments called quinacridone came onto the market. It had originally been discovered in 1896, but were not synthetized until 1936, and not manufactured until the 1950s. The colors in the group range from deep red to violet in color, and have the molecular formula C20H12N2O2. They have strong resistance to sunlight and washing, and are used in oil paints, water colors, and acrylics, as well as in automobile coatings and other industrial coatings.
Violet flowers and their color became symbolically associated with lesbian love. It was used a special code by lesbians and bisexual women for self-identification and also to communicate support for the sexual preference. This connection originates from the poet Sappho and fragments of her poems. In one poem, she describes a lost love wearing a garland of "violet tiaras, braided rosebuds, dill and crocus twined around" her neck. In another fragment, she recalls her lover as having "put around yourself [many wreaths] of violets and roses."
1,4-Diamino-2,3-dihydroanthraquinone is an anthraquinone dye used with Disperse Red 9 in colored smoke to introduce a violet color. It is also used in dyes and marine flares.Alkannin
Alkannin is a natural dye that is obtained from the extracts of plants from the borage family Alkanna tinctoria that are found in the south of France. The dye is used as a food coloring and in cosmetics. It is used as a red-brown food additive in regions such as Australia, and is designated in Europe as the E number E103, but is no longer approved for use. Alkannin has a deep red color in a greasy or oily environment and a violet color in an alkaline environment.The chemical structure as a naphthoquinone derivative was first determined by Brockmann in 1936. The enantiomer of alkannin is known as shikonin, and the racemic mixture of the two is known as shikalkin.The enzyme 4-hydroxybenzoate geranyltransferase utilizes geranyl diphosphate and 4-hydroxybenzoate to produce 3-geranyl-4-hydroxybenzoate and diphosphate. These compounds are then used to form alkannin.Alkannin is an antioxidant and has an antimicrobial effect against Staphylococcus aureus and Staphylococcus epidermidis. It is also known to have wound healing, antitumor, and antithrombotic properties.
Shikonin is also found in the Chinese herbal medicine plant Lithospermum erythrorhizon, the red-root gromwell, (紫草 zicao, Pinyin: zǐcǎo).Azapa Valley
Azapa Valley in Chile is a fertile and narrow oasis, framed between two sere hills and divided by the summer season-running "San Jose" river . It is located three kilometers from Arica. This jewel of the north has a unique climate that permits the farming of a great variety of fruits and vegetables throughout the year, in addition to the unique olives of Azapa, famous for their violet color and bitter flavor that also give birth to a strong-tasting oil.Blue laser
A blue laser is a laser that emits electromagnetic radiation with a wavelength between 360 and 480 nanometres, which the human eye sees as blue or violet.
Blue beams are produced by helium-cadmium gas lasers at 441.6 nm, and argon-ion lasers at 458 and 488 nm. Semiconductor lasers with blue beams are typically based on gallium(III) nitride (GaN; violet color) or indium gallium nitride (often true blue in color, but also able to produce other colors). Both blue and violet lasers can also be constructed using frequency-doubling of infrared laser wavelengths from diode lasers or diode-pumped solid-state lasers.
Diode lasers which emit light at 445 nm are becoming popular as handheld lasers. Lasers emitting wavelengths below 445 nm appear violet (but are sometimes called blue lasers). Some of the most commercially common blue lasers are the diode lasers used in Blu-ray applications which emit 405 nm "violet" light, which is a short enough wavelength to cause fluorescence in some chemicals, in the same way as radiation further into the ultraviolet ("black light") does. Light of a shorter wavelength than 400 nm is classified as ultraviolet.
Devices that employ blue laser light have applications in many areas ranging from optoelectronic data storage at high density to medical applications.Cereus jamacaru
Cereus jamacaru, known as mandacaru or cardeiro, is a cactus common in the Brazilian northeast which often grows up to 5 metres (20 ft) high.
A thorn-less kind is used for animal feed. The most common kind is highly thorny but is also used for animal feed, after burning or cutting off the thorns. Mandacaru is highly drought-resistant.
The flowers are white and about 30 centimetres (10 in) long. The flower buds usually appear in the middle of spring and each flower lasts only for a night. They blossom at dusk and wither by the morning . Its fruit has a very strong violet color. The pulp is white with tiny black seeds, and it is considered very tasty. Many birds feed on them, like the "gralha-cancã" and the "periquito-da-caatinga" from Brazilian caatinga.Crème de violette
Crème de violette, also known as liqueur de violette, is a generic term for a liqueur with natural and/or artificial violet flower flavoring and coloring with either a brandy base, a neutral spirit base, or a combination of the two. The taste profile and aroma are distinctly floral and sweet, and to many reminiscent of the violet candies popular in the early to mid 20th century. Its known production dates back to the early 19th century when it was served with dry vermouth or alone as a cordial.
One well-regarded brand is Benoit Serres Liqueur de Violette. However, it is reportedly very difficult to obtain even in France. Benoit Liqueur de Violette is made with a neutral spirit base with a smaller portion of Armagnac added to it.After crème de violette had been all but unavailable in the United States for decades, in mid-2007 Haus Alpenz began importing the Rothman & Winter Crème de Violette, which is made from Queen Charlotte and March violet flowers from the Alps. Since then, other brands of crème de violette have arrived on the US market, e.g., The Bitter Truth from Europe.
Crème de violette is the forerunner to the liqueurs Parfait d'Amour and the American variation, Creme Yvette, both of which are decidedly different with pronounced vanilla and/or citrus flavors. When crème de violette is not available it is possible to use the Parfait Amour or creme Yvette to replicate the violet color in a drink, though the taste profile is quite different.It is considered a core ingredient in the Aviation cocktail.The rarity of crème de violette appeared as a plot element in an episode of The Avengers in 1965 entitled "Two's A Crowd".Datura ferox
Datura ferox, commonly known as long spined thorn apple and fierce thornapple, as well as Angel's-trumpets, is a species of Datura. Like all such species, every part of the plant contains deadly toxins that can kill animals (including humans) that ingest it. Its fruit, red-brown when ripe, has unusually long thorns or spikes.
The species was first described in 1756 by Linnaeus. Ferox means "strongly fortified," referring to the fearsome-looking spines on the seed pod. It probably originated in southeastern China. Today it is found in all the warm parts of the earth, where it is regarded as a dangerous pasture weed.Datura ferox is an upright shrub 1½ to 3 feet high. Its thick stalks often have a red-violet color at the base. All the young shoots are noticeably hairy. The most conspicuous part of the plant is its very wide undulate, irregularly toothed leaves, which are covered with soft, downy hairs. The yellowish white flowers are funnel-shaped and inconspicuous, and usually do not open completely.Eggplant (color)
Eggplant is a dark purple or brownish-purple color that resembles the color of the outer skin of European eggplants. Another name for the color eggplant is aubergine (the French, German and British English word for eggplant).
The first recorded use of eggplant as a color name in English was in 1915.The pinkish-purple-grayish color shown in the color box as eggplant was introduced by Crayola in 1998.Different varieties of eggplant may range from indigo to white (the term eggplant originated as a description of white colored eggplants because they look like eggs). Chinese eggplants are the same shape as a European eggplant, but are colored a dark violet color. Thai eggplants are small, round, and colored forest green.Fraxinus caroliniana
Fraxinus caroliniana, the pop ash, Florida ash, swamp ash, Carolina ash, or water ash, is a species of ash tree native from Cuba through the subtropical southeastern United States from southern Virginia to Texas. It was originally described by the botanist Philip Miller. It is a small tree about 40 ft. Leaves are compound, opposite, 7–12 in long, leaflets 5–7 in, ovate to oblong, coarsely serrate or entire, 3–6 in long, 2–3 in wide. Fruit is frequently 3-winged (samara) with flat seed portion; seed sometimes a bright violet color. It is the smallest of eastern North American ash species, wood light, soft, weak, 22 lbs./cu.ft. Typical to coastal swamps and subtropical lowlands.Gallic acid reagent
The Gallic acid reagent is used as a simple spot-test to presumptively identify drug precursor chemicals. It is composed of a mixture of gallic acid and concentrated sulfuric acid.0.05 g of gallic acid is used for every 10 mls of sulphuric acid. The same ratio of gallic acid n-propyl ester in sulfuric acid can also be used.Because of its short shelf life (changing to pale violet color) it is sometimes prepared by dissolving gallic acid into ethanol and adding the sulfuric acid at the time of testing from a separate bottle. In this case 100 mL ethanol is used and one drop of sulfuric acid is used per drop of gallic acid in ethanol.List of colors (compact)
The following list shows a compact version of the colors in the List of colors A–F, G–M, and N–Z articles. The list shows the color and its name. Hovering over the color box shows the HSV, RGB, and #hex values for the color in the tool tip.
There are 11 main colors. The main 11 colors are red, orange, yellow, green, blue, purple, pink, brown, gray, black and white. The rest of the colors on this list are just different types, combinations and shades of the main 11 colors.Misket Cherven
Misket Cherven, meaning Red Misket, is a variety of grape used for wine. It is a white wine grape, but has a pinkish skin colour. It is spread in the Sub-Balkan Bulgarian wine regions. It is considered to be an old local variety, cultivated nowadays mainly in the Sungurlare Valley, and the Karlovo and Brezovo districts. There are also smaller plantations in the Stara Zagora, Sliven, Yambol and Vratza districts. The grape variety grows best in hilly, airy regions. The grapes are small and have pinkish-red to violet color. The wine made from Misket Cherven is typically dry. It is straw-yellow in color and often has some green nuance. Varietal Misket wines are typically named by appellation. Best known are Sungurlare Misket and Karlovo Misket, produced in two distinct wine regions in the southern outskirts of the Balkan Mountains. In table wines, Misket Cherven is often blended with Welschriesling and Dimyat.Misket Cherven is also used as a table grape.Red-violet
Red-violet is a rich color of high medium saturation about 3/4 of the way between red and magenta, closer to magenta than to red. It is classified in color theory as one of the purple colors—a non-spectral color between red and violet that is a deep version of a color on the line of purples on the CIE chromaticity diagram. Both its saturation and brightness falling short of 100%, red-violet is not a pure chroma. There is a color of similar hue that, however, comes close to being a pure chroma: process magenta. The pure chroma color composed of equal parts of magenta and red is called rose.
In the use by artists, red-violet is equivalent to purple, however, although the color "purple" is inaccurately used by many people as a synonym for violet or a color close to violet, professional artists who use the RYB color wheel generally use the term "purple" to specifically refer to a pigment color that is equivalent to red-violet (i.e., the tertiary color between violet and red on the RYB color wheel) in order to give themselves a larger and more balanced palette of pigments to work with.The Munsell color system also refers to red-violet as purple; in the Munsell color system, this color at the maximum chroma of 12 is called Red-Purple. This convention is for chromatic purposes, since Red-Purple lies between violet and printer's magenta (the color regarded as magenta before the invention of the color electric magenta for computer displays).Refosco
Refosco is a very old family of dark-skinned grape varieties native to the Venetian zone and neighbouring areas of Friuli, Gavi, Trentino, Istria, and Karst Plateau. It is considered autochthonous in these regions.
The wines this grape yields can be quite powerful and tannic, with a deep violet color and a slight bitterness. On the palate, there are strong currant, wild berry and plum flavors. The wine can stand some aging (depending on variety), and after a period of four-to-ten years, it achieves a floral quality as well. Refosco should be served at 16 °C (60.8 °F), or if it is particularly rich in tannin, at 18 °C (64.4 °F). It goes best with charcuterie, game, and grilled poultry.Salvia transsylvanica
Salvia transsylvanica is a herbaceous perennial native to a wide area from north and central Russia to Romania. It was described and named in 1853 by botanist Philipp Johann Ferdinand Schur, with the specific epithet referring to the Transylvanian Alps located in central Romania. It was introduced into horticulture in the 1980s.Salvia transsylvanica puts out several lax 2 feet (0.61 m) stems from a basal clump of leaves. The leaves that grow on the stem vary in size—being larger at the bottom—with the upper side being dark yellow-green and the underside pale with yellow veins. The leaves are very scalloped around the edges. The flowers are slightly longer than 0.5 inches (1.3 cm), and have a rich violet color, growing in loose whorls that are about .5 inches (1.3 cm) apart. Many flowers bloom at once, giving the plant a very colorful and striking appearance.Shades of purple
There are numerous variations of the color purple, a sampling of which are shown below.
In common English usage, purple is a range of hues of color occurring between red and blue.In color theory, purple colors are any colors on the line of purples on the CIE chromaticity diagram (or colors that can be derived from colors on the line of purples), i.e., any color between red and violet, not including either red or violet themselves.The first recorded use of purple as a color name in English was in 975 AD.Shades of violet
There are numerous variations of the color violet, a sampling of which are shown below.Tetraamminecopper(II) sulfate
Tetraamminecopper(II) sulfate is the inorganic compound with the formula [Cu(NH3)4(H2O)n]SO4. This dark blue solid is a metal complex with faint odour of ammonia. It is closely related to Schweizer's reagent, which is used for the production of cellulose fibers in the production of rayon. It is used to print fabrics, used as a pesticide and to make other copper compounds like copper nano-powder.Violet light
Though the violet color is normally composed of blue and red light, violet color can also be monochromatic, composed only by violet light. Combinations of red and blue lights and monochromatic light of wavelength smaller than blue produce a similar effect for the human eye due to a second resonancy of the red-sensitive cone cells.
Composed-light violet shows two colors when decomposed. Violet light from the rainbow, which can be referred as spectral violet, is composed only by a short wavelength instead. This monochromatic violet light occupies its own place at the end of the visible spectrum, and is one of the seven spectral colors described by Isaac Newton in 1672.
Violet light is at the higher end of the visible spectrum, with a wavelength ~380-450 nanometers (in experiments, people have so far seen to 310 nm). Light with a shorter wavelength than violet but longer than X-rays and gamma rays is called ultraviolet.
Violet objects are normally composed-light violet. Objects reflecting spectral violet appear very dark, because human vision is relatively insensitive to those wavelengths. Monochromatic lamps emitting spectral-violet wavelengths can be roughly approximated by the color named electric violet, which is a composed-light violet producing a similar effect to the human eye.
A typical sample is shown for each name; a range of color-variations is commonly associated with each color-name.