Cerulean

{{Short description|Shade of blue (color)}} {{Other uses}} {{pp-pc}} {| align="right" |+ Cerulean as a quaternary color on the RYB color wheel |{{legend|#0247FE|blue}} |- |{{legend|#0067A3|'''cerulean'''}} |- |{{legend|#008080|teal}} |} {{infobox Color |title=Cerulean |hex=007BA7 |source=Maerz and Paul<ref name="MaerzPaul1930C" /> |isccname=Strong greenish blue }} {{infobox Color |title=Cerulean (RGB) |hex=0040FF |isccname=Vivid blue }}

The color '''cerulean''' (American English), or '''caerulean''' (British English, Commonwealth English), is a variety of the hue of blue that may range from a light azure blue to a more intense sky blue. Cerulean may also be mixed with the hue of green. The first recorded use of ''cerulean'' as a color name in English was in 1590.<ref name="MaerzPaul1930C">{{cite book|last1=Maerz|first1=Aloys John |last2=Paul|first2=M. Rea |title=A Dictionary of Color|url=https://books.google.com/books?id=jnQ0AAAAIAAJ|year=1930|publisher=McGraw-Hill Book Company|page=190; Color Sample of Cerulean: Page 89 Plate 33 Color Sample E6}}</ref> The word is derived from the Latin word ''caeruleus'' ({{IPA|la|kaeˈruleus|lang}}), "dark blue, blue, or blue-green", which in turn probably derives from {{Lang|la|caerulum}}, diminutive of {{Lang|la|caelum}}, "heaven, sky".<ref>{{cite web|url=http://www.etymonline.com/index.php?search=cerulean&searchmode=none|title=cerulean - Search Online Etymology Dictionary|website=Etymonline.com|access-date=20 November 2017}}</ref>

"Cerulean blue" is the name of a blue-green pigment consisting of cobalt stannate ({{chem|Co|2|SnO|4}}). The pigment was first synthesized in the late eighteenth century by Albrecht Höpfner, a Swiss chemist, and it was known as Höpfner blue during the first half of the nineteenth century. Art suppliers began referring to cobalt stannate as cerulean in the second half of the nineteenth century. It was not widely used by artists until the 1870s when it became available in oil paint.<ref name=":0">{{Cite book |last=Eastlaugh |first=Nicholas |title=The pigment compendium: a dictionary of historical pigments |publisher=Elsevier Butterworth-Heinemann |year=2004 |isbn=9780750657495 |location=Amsterdam; Boston |pages=90 |language=English}}</ref>

{{infobox Color |title=Cerulean Blue |hex=2A52BE |source=Maerz and Paul<ref name="MaerzPaul1930CB">{{cite book|last1=Maerz|first1=Aloys John |last2=Paul|first2=M. Rea |title=A Dictionary of Color|url=https://books.google.com/books?id=jnQ0AAAAIAAJ|year=1930|publisher=McGraw-Hill Book Company|page=190; Color Sample of Cerulean: Page 89 Plate 33 Color Sample L9}}</ref> |isccname=Vivid blue }}

==Pigment characteristics== The primary chemical constituent of the pigment is cobalt(II) stannate ({{chem|Co|2|SnO|4}}).<ref>{{cite web |url=http://webexhibits.org/pigments/indiv/overview/ceruleanblue.html |series=Pigments through the Ages |title=Cerulean blue - Overview |website=webexhibits.org |access-date=20 November 2017}}</ref><ref>{{cite web |url=http://www.webexhibits.org/pigments/indiv/history/ceruleanblue.html |series=Pigments through the Ages |title=Cerulean blue - History |website=webexhibits.org |access-date=20 November 2017}}</ref><ref>{{cite web |title=cerulean blue |series=Material name |publisher=Museum of Fine Arts |place=Boston, MA |website=Cameo.mfa.org |url=http://cameo.mfa.org/materials/record.asp?key=2170&subkey=1977&MaterialName=cobalt&Search=Search |url-status=dead |access-date=20 November 2017 |archive-url=https://web.archive.org/web/20090203141113/http://cameo.mfa.org/materials/record.asp?key=2170&subkey=1977&MaterialName=cobalt&Search=Search |archive-date=3 February 2009}}</ref> The pigment is a greenish-blue color. In watercolor, it has a slight chalkiness. When used in oil paint, it loses this quality.<ref name=":13">{{Cite book |last=St. Clair |first=Kassia |title=The Secret Lives of Color |publisher=Penguin Publishing Group |year=2017 |isbn=9780143131144 |pages=182–183}}</ref>

Today, cobalt chromate is sometimes marketed under the cerulean blue name but is darker and greener{{efn|Rex Art color index PB 36}} than the cobalt stannate version.{{efn|Rex Art color index PB 35}} The chromate makes excellent turquoise colors and is identified by ''Rex Art'' and some other manufacturers as "cobalt turquoise".<ref>{{cite web |title=Blue |website=Paintmaking |url=http://www.paintmaking.com/blue.htm |access-date=20 November 2017 |archive-url=https://web.archive.org/web/20160303171501/http://www.paintmaking.com/blue.htm |archive-date=3 March 2016 |url-status=dead}}</ref><ref>{{cite web |title=Colormaking attributes |website=Handprint.com |url=http://www.handprint.com/HP/WCL/waterb.html |access-date=20 November 2017}}</ref>

Cerulean is inert with good light resistance, and it exhibits a high degree of stability in both watercolor and acrylic paint.<ref>Patterson, Steven. 2020. "The history of blue pigments in the Fine Arts — painting, from the perspective of a paint maker". ''Journal & Proceedings of the Royal Society of New South Wales'' 153:164-179. https://royalsoc.org.au/images/pdf/journal/153-2-04Patterson.pdf . 172.</ref>

<gallery widths="200" heights="200"> File:PB35 Bleu Céruléum.JPG|Cerulean blue PB35 File:Cerulean blue hue.png|A sample swatch of cerulean blue hue oil paint. "Hue" in this instance means that other pigments have been used to mimic the color of oil paint that contains the original pigment. File:Ceruleum.png|Cerulean blue pigment in oil. On the left as a standoil glaze over zinc white; on the right as a mass tone in oil-based paint. </gallery>

== History == Cobalt stannate pigment was first synthesized in 1789 by the Swiss chemist Albrecht Höpfner by heating roasted cobalt and tin oxides together.<ref name=":06">{{Cite book |last=Siddal |first=Ruth |title=The pigment compendium: a dictionary of historical pigments |publisher=Elsevier Butterworth-Heinemann |year=2004 |isbn=9780750657495 |location=Amsterdam; Boston |pages=90 |language=English}}</ref><ref>{{cite journal |last=Höpfner |first=Albrecht |year=1789 |title=Einige kleine Chymische Versuche vom Herausgeber |journal=Magazin für die Naturkunde Helvetiens |volume=4 |pages=41–47}}</ref> Subsequently, there was limited German production under the name of ''Cölinblau''.{{citation needed|date=April 2019}} It was generally known as Höpfner blue from the late eighteenth century until the middle of the nineteenth century.<ref name=":0" />

In the late 1850s, art suppliers begin referring to the pigment as "ceruleum" blue. ''The London Times'' of 28 December 1859 had an advertisement for "Caeruleum, a new permanent color prepared for the use of artists." Ure's ''Dictionary of Arts'' from 1875 describes the pigment as "Caeruleum ... consisting of stannate of protoxide of cobalt, mixed with stannic acid and sulphate of lime." Cerulean was also referred to as coeurleum, cerulium, ''bleu céleste'' (celestial blue). Other nineteenth century English pigment names included "ceruleum blue" and "corruleum blue". By 1935, Max Doerner referred to the pigment as cerulean, as do most modern sources, though ceruleum is still used.<ref name=":0" />

Some sources claim that cerulean blue was first marketed in the United Kingdom by colourman George Rowney, as "coeruleum" in the early 1860s. However, the British firm of Roberson was buying "Blue No. 58 (Cerulium)" from a German firm of Frauenknecht and Stotz prior to Rowney.<ref name=":0" /> Cerulean blue was only available as a watercolor in the 1860s and was not widely adopted until the 1870s when it was used in oil paint. It was popular with artists including Claude Monet, Paul Signac, and Picasso. Van Gogh created his own approximation of cerulean blue using a mixture of cobalt blue, cadmium yellow, and white.<ref name=":13"/>

== In popular culture == An iconic scene in the film ''The Devil Wears Prada'' depicts Miranda Priestly (Meryl Streep) explaining the influence of the fashion industry on consumer choices of colors. In the monologue, she dissects Andrea Sachs's (Anne Hathaway) seemingly ordinary blue sweater, highlighting its "cerulean" color. The sequence, often referred to as the "cerulean sweater speech", is widely cited as an illustration of how fashion trends move from the runway to the mass market.<ref>{{cite web |title=The ‘cerulean sweater’ speech from The Devil Wears Prada, explained |url=https://www.vanityfair.com/style/2016/04/the-devil-wears-prada-cerulean-speech |website=Vanity Fair}}</ref><ref>{{cite magazine |first=Francesca |last=Wallace |title=The cerulean scene from The Devil Wears Prada was almost about another fashion trend |date=November 20, 2018 |access-date=May 7, 2026 |url=https://www.vogue.com.au/fashion/news/the-cerulean-scene-from-the-devil-wears-prada-was-almost-about-another-fashion-trend/news-story/e889de65a03ce62764e6ab8c52d18eb4y |magazine=Vogue |archive-date=November 20, 2018 |archive-url=https://web.archive.org/web/20181120073140/https://www.vogue.com.au/fashion/news/the-cerulean-scene-from-the-devil-wears-prada-was-almost-about-another-fashion-trend/news-story/e889de65a03ce62764e6ab8c52d18eb4 |url-status=live}}</ref>

== Notable occurrences == In 1877, Monet had added the pigment to his palette, using it in a painting from his series ''La Gare Saint-Lazare'' (now in the National Gallery, London). The blues in the painting include cobalt and cerulean blue, with some areas of ultramarine. Laboratory analysis conducted by the National Gallery identified a relatively pure example of cerulean blue pigment in the shadows of the station's canopy. Researchers at the National Gallery suggested that "cerulean probably offered a pigment of sufficiently greenish tone to displace Prussian blue, which may not have been popular by this time".<ref>Roy, Ashok. "The Palettes of Three Impressionist Paintings". ''National Gallery Technical Bulletin'' 9 (1985): 13. {{JSTOR|42616026}}.</ref>

Berthe Morisot painted the blue coat of the woman in her ''Summer's Day'', 1879 in cerulean blue in conjunction with artificial ultramarine and cobalt blue.<ref>{{cite book |last1=Bomford |first1=D. |title=Impressionism |last2=Kirby |first2=J. |last3=Leighton |first3=J. |last4=Roy |first4=A. |publisher=National Gallery Publications |year=1990 |series=Art in the Making |place=London, UK |pages=176–181}}</ref>

When the United Nations was formed at the end of World War II, they adopted cerulean blue for their emblem. The designer Oliver Lundquist stated that he chose the color because it was "the opposite of red, the color of war".<ref name=":13"/>

In the Catholic Church, cerulean vestments are permitted on certain Marian feast days, primarily the Immaculate Conception in diocese currently or formerly under the Spanish Crown.<ref>{{cite web| url=https://www.liturgicalartsjournal.com/2021/12/the-spanish-privilege-cerulean-blue-and.html| title=The Spanish Privilege: Cerulean Blue and the Immaculate Conception| author=Shawn Tribe| accessdate=2023-07-31 }}</ref><gallery mode="packed" widths="200" heights="200"> File:Cerulean warbler catoctin mountain park 5.29.23 DSC 1869-topaz-denoiseraw.jpg|Cerulean warbler (''Setophaga cerulea''), named from its color File:The Saint-Lazare Railway Station 1522133478-43f10.jpg|Claude Monet, ''La Gare Saint-Lazare,'' 1887 File:Berthe Morisot - Jour d'été, 1879.jpg|Berthe Morisot, Summer's Day, 1879 File:Flag-United-Nations-Logo.jpg|Symbol of the United Nations </gallery>

==Other color variations==

===Pale cerulean=== {{infobox color |title=Cerulean (Pantone) |hex=98B4D4 |source=Pantone TPX<ref>[http://www.pantone.com/pages/pantone/colorfinder.aspx Pantone TPX]</ref><ref>Type the word "Cerulean" into the indicated window on the Pantone Color Finder and the color will appear.</ref> |isccname=Pale blue}}

Pantone, in a press release, declared the pale hue of cerulean at right, which they call ''cerulean'', as the "color of the millennium".<ref name="pantone">{{cite web|url=https://www.pantone.com/|title=About Us - Color the Millennium Cerulean Blue|last=PANTONE|website=PANTONE|access-date=20 November 2017}}</ref>

The source of this color is the "Pantone Textile Paper eXtended (TPX)" color list, color #15-4020 TPX—Cerulean.<ref>{{cite web|url=http://www.pantone.com/pages/pantone/colorfinder.aspx|title=- Find a Pantone Color - Quick Online Color Tool|website=Pantone.com|access-date=20 November 2017}}</ref> {{Clear}}

=== Cerulean (Crayola) === {{infobox color |title=Cerulean (Crayola) |hex=02A4D3 |source=Crayola |isccname=Brilliant greenish blue}}

This bright tone of cerulean is the color called ''cerulean'' by Crayola crayons. {{Clear}}

===Cerulean frost=== {{infobox color |title=Cerulean Frost |hex=6D9BC3 |source=Crayola |isccname=Light blue}}

At right is displayed the color '''cerulean frost'''.

''Cerulean frost'' is one of the colors in the special set of metallic colored Crayola crayons called Silver Swirls, the colors of which were formulated by Crayola in 1990. {{Clear}}

===Curious Blue=== {{infobox color |title=Curious Blue |hex=269DCE |source=hexcolor.co<ref>{{Cite web|url=https://hexcolor.co/hex/269dce|title=#269dce - Curious Blue - RGB 38, 157, 206 Color Information|first=Bettie M.|last=Cobb|website=HEX Colors}}</ref> |isccname=Moderate cerulean}}

Curious Blue is one of the brighter-toned colors of cerulean. {{Clear}}

==In nature== * Cerulean cuckooshrike * Cerulean kingfisher * Cerulean flycatcher * Cerulean warbler * Cerulean-capped manakin

==See also== * {{Section link|The Devil Wears Prada (film)|Cerulean sweater speech}} * {{Section link|Pusher (The X-Files)|Plot}} * List of colors * Pigment * Blue pigments

== Explanatory notes == {{notelist}}

==References== {{reflist|30em}}

==External links== * [https://www.webexhibits.org//pigments/indiv/overview/ceruleanblue.html A page on Cerulean Blue] * [http://colourlex.com/project/cerulean-blue/ Cerulean blue] at ColourLex

Category:Quaternary colors Category:Pigments Category:Inorganic pigments Category:Shades of azure Category:Shades of blue Category:Shades of cyan Category:Bird colours Category:Cobalt compounds