Green

context: The modern English word green comes from the Middle English and Anglo-Saxon word grene, from the same Germanic root as the words "grass" and "grow". It is the color of living grass and leaves and as a result is the color most associated with springtime, growth and nature. By far the largest contributor to green in nature is chlorophyll, the chemical by which plants photosynthesize and convert sunlight into chemical energy. Many creatures have adapted to their green environments by taking on a green hue themselves as camouflage. Several minerals have a green color, including the emerald, which is colored green by its chromium content.

context: In surveys made in Europe and the United States, green is the color most commonly associated with nature, life, health, youth, spring, hope and envy. In Europe and the U.S. green is sometimes associated with death (green has several seemingly contrary associations), sickness, or the devil, but in China its associations are very positive, as the symbol of fertility and happiness. In the Middle Ages and Renaissance, when the color of clothing showed the owner's social status, green was worn by merchants, bankers and the gentry, while red was the color of the nobility. The Mona Lisa by Leonardo da Vinci wears green, showing she is not from a noble family; the benches in the British House of Commons are green, while those in the House of Lords are red. Green is also the traditional color of safety and permission; a green light means go ahead, a green card permits permanent residence in the United States. It is the most important color in Islam. It was the color of the banner of Muhammad, and is found in the flags of nearly all Islamic countries, and represents the lush vegetation of Paradise. It is also often associated with the culture of Gaelic Ireland, and is a color of the flag of Ireland. Because of its association with nature, it is the color of the environmental movement. Political groups advocating environmental protection and social justice describe themselves as part of the Green movement, some naming themselves Green parties. This has led to similar campaigns in advertising, as companies have sold green, or environmentally friendly, products.

context: Thus, the languages mentioned above (Germanic, Romance, Slavic, Greek) have old terms for "green" which are derived from words for fresh, sprouting vegetation. However, comparative linguistics makes clear that these terms were coined independently, over the past few millennia, and there is no identifiable single Proto-Indo-European or word for "green". For example, the Slavic zelenъ is cognate with Sanskrit hari "yellow, ochre, golden". The Turkic languages also have jašɨl "green" or "yellowish green", compared to a Mongolian word for "meadow".

context: In some languages, including old Chinese, Thai, old Japanese, and Vietnamese, the same word can mean either blue or green. The Chinese character 青 (pronounced qīng in Mandarin, ao in Japanese, and thanh in Sino-Vietnamese) has a meaning that covers both blue and green; blue and green are traditionally considered shades of "青". In more contemporary terms, they are 藍 (lán, in Mandarin) and 綠 (lǜ, in Mandarin) respectively. Japanese also has two terms that refer specifically to the color green, 緑 (midori, which is derived from the classical Japanese descriptive verb midoru "to be in leaf, to flourish" in reference to trees) and グリーン (guriin, which is derived from the English word "green"). However, in Japan, although the traffic lights have the same colors that other countries have, the green light is described using the same word as for blue, "aoi", because green is considered a shade of aoi; similarly, green variants of certain fruits and vegetables such as green apples, green shiso (as opposed to red apples and red shiso) will be described with the word "aoi". Vietnamese uses a single word for both blue and green, xanh, with variants such as xanh da trời (azure, lit. "sky blue"), lam (blue), and lục (green; also xanh lá cây, lit. "leaf green").

context: "Green" in modern European languages corresponds to about 520–570 nm, but many historical and non-European languages make other choices, e.g. using a term for the range of ca. 450–530 nm ("blue/green") and another for ca. 530–590 nm ("green/yellow").[citation needed] In the comparative study of color terms in the world's languages, green is only found as a separate category in languages with the fully developed range of six colors (white, black, red, green, yellow, and blue), or more rarely in systems with five colors (white, red, yellow, green, and black/blue). (See distinction of green from blue) These languages have introduced supplementary vocabulary to denote "green", but these terms are recognizable as recent adoptions that are not in origin color terms (much like the English adjective orange being in origin not a color term but the name of a fruit). Thus, the Thai word เขียว besides meaning "green" also means "rank" and "smelly" and holds other unpleasant associations.

context: In the subtractive color system, used in painting and color printing, green is created by a combination of yellow and blue, or yellow and cyan; in the RGB color model, used on television and computer screens, it is one of the additive primary colors, along with red and blue, which are mixed in different combinations to create all other colors. On the HSV color wheel, also known as the RGB color wheel, the complement of green is magenta; that is, a color corresponding to an equal mixture of red and blue light (one of the purples). On a traditional color wheel, based on subtractive color, the complementary color to green is considered to be red.

context: In additive color devices such as computer displays and televisions, one of the primary light sources is typically a narrow-spectrum yellowish-green of dominant wavelength ~550 nm; this "green" primary is combined with an orangish-red "red" primary and a purplish-blue "blue" primary to produce any color in between – the RGB color model. A unique green (green appearing neither yellowish nor bluish) is produced on such a device by mixing light from the green primary with some light from the blue primary.

context: Lasers emitting in the green part of the spectrum are widely available to the general public in a wide range of output powers. Green laser pointers outputting at 532 nm (563.5 THz) are relatively inexpensive compared to other wavelengths of the same power, and are very popular due to their good beam quality and very high apparent brightness. The most common green lasers use diode pumped solid state (DPSS) technology to create the green light. An infrared laser diode at 808 nm is used to pump a crystal of neodymium-doped yttrium vanadium oxide (Nd:YVO4) or neodymium-doped yttrium aluminium garnet (Nd:YAG) and induces it to emit 281.76 THz (1064 nm). This deeper infrared light is then passed through another crystal containing potassium, titanium and phosphorus (KTP), whose non-linear properties generate light at a frequency that is twice that of the incident beam (563.5 THz); in this case corresponding to the wavelength of 532 nm ("green"). Other green wavelengths are also available using DPSS technology ranging from 501 nm to 543 nm. Green wavelengths are also available from gas lasers, including the helium–neon laser (543 nm), the Argon-ion laser (514 nm) and the Krypton-ion laser (521 nm and 531 nm), as well as liquid dye lasers. Green lasers have a wide variety of applications, including pointing, illumination, surgery, laser light shows, spectroscopy, interferometry, fluorescence, holography, machine vision, non-lethal weapons and bird control.

context: Many minerals provide pigments which have been used in green paints and dyes over the centuries. Pigments, in this case, are minerals which reflect the color green, rather that emitting it through luminescent or phosphorescent qualities. The large number of green pigments makes it impossible to mention them all. Among the more notable green minerals, however is the emerald, which is colored green by trace amounts of chromium and sometimes vanadium. Chromium(III) oxide (Cr2O3), is called chrome green, also called viridian or institutional green when used as a pigment. For many years, the source of amazonite's color was a mystery. Widely thought to have been due to copper because copper compounds often have blue and green colors, the blue-green color is likely to be derived from small quantities of lead and water in the feldspar. Copper is the source of the green color in malachite pigments, chemically known as basic copper(II) carbonate.

context: Verdigris is made by placing a plate or blade of copper, brass or bronze, slightly warmed, into a vat of fermenting wine, leaving it there for several weeks, and then scraping off and drying the green powder that forms on the metal. The process of making verdigris was described in ancient times by Pliny. It was used by the Romans in the murals of Pompeii, and in Celtic medieval manuscripts as early as the 5th century AD. It produced a blue-green which no other pigment could imitate, but it had drawbacks; it was unstable, it could not resist dampness, it did not mix well with other colors, it could ruin other colors with which it came into contact., and it was toxic. Leonardo da Vinci, in his treatise on painting, warned artists not to use it. It was widely used in miniature paintings in Europe and Persia in the 16th and 17th centuries. Its use largely ended in the late 19th century, when it was replaced by the safer and more stable chrome green. Viridian, also called chrome green, is a pigment made with chromium oxide dihydrate, was patented in 1859. It became popular with painters, since, unlike other synthetic greens, it was stable and not toxic. Vincent van Gogh used it, along with Prussian blue, to create a dark blue sky with a greenish tint in his painting Cafe terrace at night.

context: There is no natural source for green food colorings which has been approved by the US Food and Drug Administration. Chlorophyll, the E numbers E140 and E141, is the most common green chemical found in nature, and only allowed in certain medicines and cosmetic materials. Quinoline Yellow (E104) is a commonly used coloring in the United Kingdom but is banned in Australia, Japan, Norway and the United States. Green S (E142) is prohibited in many countries, for it is known to cause hyperactivity, asthma, urticaria, and insomnia.

context: To create green sparks, fireworks use barium salts, such as barium chlorate, barium nitrate crystals, or barium chloride, also used for green fireplace logs. Copper salts typically burn blue, but cupric chloride (also known as "campfire blue") can also produce green flames. Green pyrotechnic flares can use a mix ratio 75:25 of boron and potassium nitrate. Smoke can be turned green by a mixture: solvent yellow 33, solvent green 3, lactose, magnesium carbonate plus sodium carbonate added to potassium chlorate.

context: Green is common in nature, as many plants are green because of a complex chemical known as chlorophyll, which is involved in photosynthesis. Chlorophyll absorbs the long wavelengths of light (red) and short wavelengths of light (blue) much more efficiently than the wavelengths that appear green to the human eye, so light reflected by plants is enriched in green. Chlorophyll absorbs green light poorly because it first arose in organisms living in oceans where purple halobacteria were already exploiting photosynthesis. Their purple color arose because they extracted energy in the green portion of the spectrum using bacteriorhodopsin. The new organisms that then later came to dominate the extraction of light were selected to exploit those portions of the spectrum not used by the halobacteria.

context: Animals typically use the color green as camouflage, blending in with the chlorophyll green of the surrounding environment. Green animals include, especially, amphibians, reptiles, and some fish, birds and insects. Most fish, reptiles, amphibians, and birds appear green because of a reflection of blue light coming through an over-layer of yellow pigment. Perception of color can also be affected by the surrounding environment. For example, broadleaf forests typically have a yellow-green light about them as the trees filter the light. Turacoverdin is one chemical which can cause a green hue in birds, especially. Invertebrates such as insects or mollusks often display green colors because of porphyrin pigments, sometimes caused by diet. This can causes their feces to look green as well. Other chemicals which generally contribute to greenness among organisms are flavins (lychochromes) and hemanovadin. Humans have imitated this by wearing green clothing as a camouflage in military and other fields. Substances that may impart a greenish hue to one's skin include biliverdin, the green pigment in bile, and ceruloplasmin, a protein that carries copper ions in chelation.

context: There is no green pigment in green eyes; like the color of blue eyes, it is an optical illusion; its appearance is caused by the combination of an amber or light brown pigmentation of the stroma, given by a low or moderate concentration of melanin, with the blue tone imparted by the Rayleigh scattering of the reflected light. Green eyes are most common in Northern and Central Europe. They can also be found in Southern Europe, West Asia, Central Asia, and South Asia. In Iceland, 89% of women and 87% of men have either blue or green eye color. A study of Icelandic and Dutch adults found green eyes to be much more prevalent in women than in men. Among European Americans, green eyes are most common among those of recent Celtic and Germanic ancestry, about 16%.

context: In Ancient Egypt green was the symbol of regeneration and rebirth, and of the crops made possible by the annual flooding of the Nile. For painting on the walls of tombs or on papyrus, Egyptian artists used finely-ground malachite, mined in the west Sinai and the eastern desert- A paintbox with malachite pigment was found inside the tomb of King Tutankhamun. They also used less expensive green earth pigment, or mixed yellow ochre and blue azurite. To dye fabrics green, they first colored them yellow with dye made from saffron and then soaked them in blue dye from the roots of the woad plant.

context: For the ancient Egyptians, green had very positive associations. The hieroglyph for green represented a growing papyrus sprout, showing the close connection between green, vegetation, vigor and growth. In wall paintings, the ruler of the underworld, Osiris, was typically portrayed with a green face, because green was the symbol of good health and rebirth. Palettes of green facial makeup, made with malachite, were found in tombs. It was worn by both the living and dead, particularly around the eyes, to protect them from evil. Tombs also often contained small green amulets in the shape of scarab beetles made of malachite, which would protect and give vigor to the deceased. It also symbolized the sea, which was called the "Very Green."

context: In Ancient Greece, green and blue were sometimes considered the same color, and the same word sometimes described the color of the sea and the color of trees. The philosopher Democritus described two different greens; cloron, or pale green, and prasinon, or leek green. Aristotle considered that green was located midway between black, symbolizing the earth, and white, symbolizing water. However, green was not counted among of the four classic colors of Greek painting; red, yellow, black and white, and is rarely found in Greek art.

context: The Romans had a greater appreciation for the color green; it was the color of Venus, the goddess of gardens, vegetables and vineyards.The Romans made a fine green earth pigment, which was widely used in the wall paintings of Pompeii, Herculaneum, Lyon, Vaison-la-Romaine, and other Roman cities. They also used the pigment verdigris, made by soaking copper plates in fermenting wine. By the Second Century AD, the Romans were using green in paintings, mosaics and glass, and there were ten different words in Latin for varieties of green.

context: Unfortunately for those who wanted or were required to wear green, there were no good vegetal green dyes which resisted washing and sunlight. Green dyes were made out of the fern, plantain, buckthorn berries, the juice of nettles and of leeks, the digitalis plant, the broom plant, the leaves of the fraxinus, or ash tree, and the bark of the alder tree, but they rapidly faded or changed color. Only in the 16th century was a good green dye produced, by first dyeing the cloth blue with woad, and then yellow with reseda luteola, also known as yellow-weed.

context: In the 18th and 19th century, green was associated with the romantic movement in literature and art. The French philosopher Jean-Jacques Rousseau celebrated the virtues of nature, The German poet and philosopher Goethe declared that green was the most restful color, suitable for decorating bedrooms. Painters such as John Constable and Jean-Baptiste-Camille Corot depicted the lush green of rural landscapes and forests. Green was contrasted to the smoky grays and blacks of the Industrial Revolution.

context: The late nineteenth century also brought the systematic study of color theory, and particularly the study of how complementary colors such as red and green reinforced each other when they were placed next to each other. These studies were avidly followed by artists such as Vincent van Gogh. Describing his painting, The Night Cafe, to his brother Theo in 1888, Van Gogh wrote: "I sought to express with red and green the terrible human passions. The hall is blood red and pale yellow, with a green billiard table in the center, and four lamps of lemon yellow, with rays of orange and green. Everywhere it is a battle and antithesis of the most different reds and greens."

context: Green can communicate safety to proceed, as in traffic lights. Green and red were standardized as the colors of international railroad signals in the 19th century. The first traffic light, using green and red gas lamps, was erected in 1868 in front of the Houses of Parliament in London. It exploded the following year, injuring the policeman who operated it. In 1912, the first modern electric traffic lights were put up in Salt Lake City, Utah. Red was chosen largely because of its high visibility, and its association with danger, while green was chosen largely because it could not be mistaken for red. Today green lights universally signal that a system is turned on and working as it should. In many video games, green signifies both health and completed objectives, opposite red.

context: Like other common colors, green has several completely opposite associations. While it is the color most associated by Europeans and Americans with good health, it is also the color most often associated with toxicity and poison. There was a solid foundation for this association; in the nineteenth century several popular paints and pigments, notably verdigris, vert de Schweinfurt and vert de Paris, were highly toxic, containing copper or arsenic.[d] The intoxicating drink absinthe was known as "the green fairy".

context: Many flags of the Islamic world are green, as the color is considered sacred in Islam (see below). The flag of Hamas, as well as the flag of Iran, is green, symbolizing their Islamist ideology. The 1977 flag of Libya consisted of a simple green field with no other characteristics. It was the only national flag in the world with just one color and no design, insignia, or other details. Some countries used green in their flags to represent their country's lush vegetation, as in the flag of Jamaica, and hope in the future, as in the flags of Portugal and Nigeria. The green cedar of Lebanon tree on the Flag of Lebanon officially represents steadiness and tolerance.

context: In the 1980s green became the color of a number of new European political parties organized around an agenda of environmentalism. Green was chosen for its association with nature, health, and growth. The largest green party in Europe is Alliance '90/The Greens (German: Bündnis 90/Die Grünen) in Germany, which was formed in 1993 from the merger of the German Green Party, founded in West Germany in 1980, and Alliance 90, founded during the Revolution of 1989–1990 in East Germany. In the 2009 federal elections, the party won 10.7% of the votes and 68 out of 622 seats in the Bundestag.

context: Roman Catholic and more traditional Protestant clergy wear green vestments at liturgical celebrations during Ordinary Time. In the Eastern Catholic Church, green is the color of Pentecost. Green is one of the Christmas colors as well, possibly dating back to pre-Christian times, when evergreens were worshiped for their ability to maintain their color through the winter season. Romans used green holly and evergreen as decorations for their winter solstice celebration called Saturnalia, which eventually evolved into a Christmas celebration. In Ireland and Scotland especially, green is used to represent Catholics, while orange is used to represent Protestantism. This is shown on the national flag of Ireland.