Violet summers

On this Wikipedia the language links are at the top of the page violet summers from the article title. This article is about the color. Violet is the color of light at the short wavelength end of the visible spectrum, between blue and invisible ultraviolet. In the RGB color model used in computer and television screens, violet is produced by mixing red and blue light, with more blue than red.

Violet is closely associated with purple. Violet has a long history of association with royalty, originally because Tyrian purple dye was extremely expensive in antiquity. The emperors of Rome wore purple togas, as did the Byzantine emperors. The line of purples circled on the CIE chromaticity diagram. The bottom left of the curved edge is violet.

Points near and along the circled edge are purple. The word violet as a color name derives from the Middle English and Old French violete, in turn from the Latin viola, names of the violet flower. Violet is at one end of the spectrum of visible light, between blue light, which has a longer wavelength, and ultraviolet light, which has a shorter wavelength and is not visible to humans. Violet encompasses light with a wavelength of approximately 380 to 435 nanometers.

The earliest violet pigments used by humans, found in prehistoric cave paintings, were made from the minerals manganese and hematite. The most famous violet-purple dye in the ancient world was Tyrian purple, made from a type of sea snail called the murex, found around the Mediterranean. In western Polynesia, residents of the islands made a violet dye similar to Tyrian purple from the sea urchin. Orcein, or purple moss, was another common violet dye. 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. 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. 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. In the 1950s, a new family of violet synthetic organic pigments called quinacridones came onto the market. They had originally been discovered in 1896, synthetized in 1936 and manufactured in the 1950s.