Aureolin (sometimes called
cobalt yellow
Potassium hexanitritocobaltate(III) is a salt with the formula K3 o(NO2)6 It is a yellow solid that is poorly soluble in water. The compound finds some use as a yellow pigment under the name Indian Yellow.
The salt features potassium cations ...
) is a pigment sparingly used in oil and watercolor painting. Its color index name is PY40 (40th entry on list of yellow pigments). It was first made in 1831 by
Nikolaus Wolfgang Fischer
Nikolaus Wolfgang Fischer (15 January 1782 – 19 August 1850) was a German chemist
A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemis ...
in
Breslau characterizing it as "Doppelsalze" or double-salts and its chemical composition is
potassium cobaltinitrite. He characterized it again and wrote more extensively about it in 1842, naming it "Salpetrichtsaures Kobaltoxydkali". In 1851-1852, Edouard Saint-Evre synthesized cobalt yellow independently. He is credited with the introduction of cobalt yellow as an artists pigment. The investigation by Gates gives the exact modern procedures for the preparation of aureolin and also the methods for its identification in paintings.
-
Aureolin is rated as permanent in some reports but there are other sources which rate it as unstable in oils but pronounce it stable in watercolors. Others find it unstable in watercolors, fading to greyish or brownish hues.
Pigments: aureolin
/ref> It is a transparent, lightly staining, light valued, intense medium yellow pigment.
It is a rather expensive pigment and sold by several manufacturers of oil paints such as Grumbacher, Michael Harding, and Holbein. However, the pigment was never popular as an oil color and is much more widely available as a watercolor from manufacturers such as: Winsor & Newton
Winsor & Newton (also abbreviated W&N) is an English manufacturing company based in London that produces a wide variety of fine art products, including acrylics, oils, watercolour, gouache, brushes, canvases, papers, inks, graphite and colour ...
, Talens Rembrandt, Rowney Artists, Sennelier, Art Spectrum and Daniel Smith.
See also
* List of colors
These are the lists of colors;
* List of colors: A–F
* List of colors: G–M
* List of colors: N–Z
* List of colors (compact)
* List of colors by shade
* List of color palettes
* List of Crayola crayon colors
* List of RAL colors
* List of X ...
* List of inorganic pigments
The following list includes commercially or artistically important inorganic pigments of natural and synthetic origin..
Purple pigments
Aluminum pigments
* Ultramarine violet: (PV15) - a synthetic or naturally occurring sulfur containing silic ...
References
{{Shades of yellow
Pigments
Inorganic pigments
Shades of yellow