Editing Blue (section)

===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, and [[natron]]. 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 maker [[Johann Jacob Diesbach]] discovered [[Prussian 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 painter [[Antoine Watteau]], and later his successor [[Nicolas Lancret]]. It became immensely popular for the manufacture of wallpaper, and in the 19th century was widely used by French impressionist painters.<ref>Michel Pastoureau, ''Bleu – Histoire d'une couleur'', pp.&nbsp;114–16</ref> Beginning in the 1820s, Prussian blue was imported into Japan through the port of [[Nagasaki]]. It was called ''bero-ai'', or Berlin blue, and it became popular because it did not fade like traditional Japanese blue pigment, ''ai-gami'', made from the [[dayflower]]. Prussian blue was used by both [[Hokusai]], in his wave paintings, and [[Hiroshige]].<ref>Roger Keyes, ''Japanese Woodblock Prints: A Catalogue of the Mary A. Ainsworth Collection'', R, Allen Memorial Art Museum, Oberlin College, 1984, p. 42, plate #140, p. 91 and catalogue entry #439, p. 185. for more on the story of Prussian blue in Japanese prints, see also the website of the Victoria and Albert Museum, London.</ref>

In 1799 a French chemist, [[Louis Jacques Thénard]], made a synthetic cobalt blue pigment which became immensely popular with painters.

In 1824 the [[Societé pour l'Encouragement d'Industrie]] in France offered a prize for the invention of an artificial [[ultramarine]] which 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 Gmelin]] then 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.<ref>Maerz and Paul (1930). ''A Dictionary of Color'' New York: McGraw Hill p. 206</ref>

In 1878 German chemists synthesized [[Indigo dye|indigo]]. This product rapidly replaced natural indigo, wiping out vast farms growing indigo. It is now the blue of blue jeans. As the pace of [[organic chemistry]] accelerated, a succession of synthetic blue dyes were discovered including [[Indanthrone blue]], which had even greater resistance to fading during washing or in the sun, and [[copper phthalocyanine]].
<gallery mode="packed" heights="200px">
File:The Blue Boy.jpg|''[[The Blue Boy]]'' (1770), featuring lapis lazuli, indigo, and cobalt colourants,<ref>{{Cite web |title=Eight blue moments in art history |url=https://www.tate.org.uk/context-comment/blogs/eight-blue-moments-art-history  |archive-url=https://web.archive.org/web/20181016130010/https://www.tate.org.uk/context-comment/blogs/eight-blue-moments-art-history |archive-date=2018-10-16 |access-date=2018-10-16 |publisher=The Tate}}</ref>
File:Great Wave off Kanagawa2.jpg|''[[The Great Wave off Kanagawa]]'' illustrates the use of [[Prussian blue]]
File:Indigoproduktion BASF 1890.JPG|A synthetic indigo dye factory in Germany in 1890.
</gallery>