View source for 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 [[blue|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 language|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 ''[[wikt:caeruleus|caeruleus]]'' ({{IPA|la|kae̯ˈru.le.us|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 [[Monochromate|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 painting|watercolor]] and [[Acrylic paint|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 oxide]]s 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 Times|''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 (artist)|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 [[Pablo Picasso|Picasso]]. [[Vincent van Gogh|Van Gogh]] created his own approximation of cerulean blue using a mixture of [[cobalt blue]], [[cadmium yellow]], and white.<ref name=":13"/>

== Notable occurrences ==
In 1877, [[Claude Monet|Monet]] had added the pigment to his palette, using it in a painting from his series ''[[Gare Saint-Lazare (Monet series)|La Gare Saint-Lazare]]'' (now in the National Gallery, London). The blues in the painting include [[Cobalt blue|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 Lincoln Lundquist|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 [[Mary, mother of Jesus|Marian]] feast days, primarily the [[Immaculate Conception]] in diocese currently or formerly under the [[Monarchy of Spain|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=[[List of Crayola crayon colors|Crayola]]
|isccname=Brilliant greenish blue}}

This bright tone of cerulean is the color called ''cerulean'' by [[List of Crayola crayon colors|Crayola crayons]].
{{Clear}}

===Cerulean frost===
{{infobox color
|title=Cerulean Frost
|hex=6D9BC3
|source=[[List of Crayola crayon colors#Silver Swirls|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 [[List of Crayola crayon colors#Silver Swirls|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

{{Shades of blue}}
{{Shades of green}}
{{Shades of cyan}}

{{Color topics}}

[[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]]