Cobalt blue



Cobalt
— Colour coordinates —
Hex triplet #0047AB
RGBB (b) (0, 71, 171)
HSV (h, s, v) (215°, 100%, 67%)
Source BF2S Color Guide
B: Normalized to [0–255] (byte)

Cobalt is a cool, slightly desaturated blue colour, historically made using aluminium oxide, or cobalt(II) aluminate, CoAl2O4. Commercial production began in France in 1807. It is made by sintering the stoichiometric mixture of finely ground CoO and Al2O3 at 1200°C.

The first recorded use of cobalt blue as a color name in English was in 1777. [1]

Cobalt blue in human culture

Art

  • John Varley suggested cobalt blue as a good substitution for ultramarine blue for painting skies.
  • Maxfield Parrish, famous partly for the intensity of his skyscapes, used cobalt blue, and cobalt blue is sometimes called Parrish blue as a result.

Construction

  • Because of its chemical stability in the presence of alkali, cobalt blue is used as a pigment in blue concrete.

Glassmaking

  • The blue seen on many glassware pieces is cobalt blue, and it is used widely by artists in many other fields.

Ophthalmology

  • "Cobalt Blue" is used a filter used in ophthalmoscopes, and is used to illuminate the cornea of the eye following application of fluorescein dye which is used to detect corneal ulcers and scratches.

References

  1. ^ Maerz and Paul A Dictionary of Color New York:1930 McGraw-Hill Page 91; Color Sample of Cobalt Blue: Page 131 Plate 34 Color Sample L7

See also

  • List of colours
 v • d • e 
Air Force blue Alice blue Azure Baby blue Blue Cerulean Cerulean blue Cobalt blue Columbia blue Cornflower blue Dark blue
                     
Denim Dodger blue Egyptian blue Electric blue Han Purple Indigo International Klein Blue Light blue Maya Blue Midnight blue Navy blue
                     
Periwinkle Persian blue Powder blue Prussian blue Royal blue Sapphire Sky blue Steel blue Ultramarine
                 
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Cobalt_blue". A list of authors is available in Wikipedia.