Colour Story: Chromium Oxide Green

oxide green

The average number of colours humans can distinguish is around a million. This varies such as with colour blindness or, at the opposite end of the spectrum, with ‘tetrachromats’; rare individuals with a genetic mutation who can see up to 100 million colours. However, what humans do have in common is a shared ability to recognise variations of green better than any other colour.

A short explanation to this commonality is human evolution’s connection to our ancestral past and its predominantly green habitat where food or prey could be identified. To this day strong associations with green remain rooted deep in our DNA, and the word ‘green’ itself is an abbreviation for many concepts; from living a ‘green’ healthy way of life or holding the political views of the ‘green’ party.

Many other species have also found ways of responding to this colour such as the walking-leaf-insect, which not only adopts the green colour of its environment but the very shapes and surface texture of leaves to achieve a perfect camouflage. In the pigment world one of the most stable green pigments is Chromium Oxide Green; also known as Chrome Green. Chromium Oxide Green can be found in nature as Eskolaite, named after the Finnish geologist Pentti Eskola. An uncanny feature of this rare mineral is the way its metallic vitreous green surface has a camouflaging moss-like appearance in the natural world.

Since the 1800s many inorganic pigments have been manufactured synthetically and Chromium Oxide Green is amongst those resulting from the scientific revolution during the 19th century which produced many synthetic dyes and pigments previously only found in nature as minerals (inorganic pigments) or sourced from carbon-based organism such as insects or plants (organic pigments). In 1838 the artist-chemist Antoine-Claude Pannetier was the first to manufacture the Chromium Oxide pigment; a method which would later be patented by Charles-Ernest Guignet in 1859. George Field was also known for making this colour but it is unclear from his notes whether this was the hydrous transparent Chromium Oxide, sometimes known as Viridian, or the anhydrous Chromium Oxide associated with the highly opaque Chromium Oxide Green.

Not surprisingly one of the most common uses for Chromium Oxide Green is in camouflage paint. Until the 18th century many military uniforms were purposely brightly coloured so as to be seen from afar by the enemy, but the British Army were the first to recognise the advantages of disguise when they began in 1850 to dye their otherwise bright white uniforms a sandy off-white colour designed to blend in with the desert; calling these new uniforms khakis, a Hindu word for ‘dust’. As blending-in, rather than standing-out, developed as a military tactic, camouflage in various forms emerged through a combination of research.

The zoologist Sir Edward Poulton wrote The Colours of Animals (1890) the first book describing camouflage in nature, and the American painter Abbott Thayer’s article The Law Which Underlies Protective Coloration (1896) described schematised forms of common camouflaging found in nature such as countershading and disruptive coloration. By 1914 French units in the army called camoufleurs, were teaching the art of disguising equipment through the use of fake leaves, netting or paint, and Lucien-Victor Guirand de Scévola, a French painter serving in the infantry, brought ideas of Picasso’s geometric Cubist forms into the design of camouflage.

As camouflage has evolved it has developed as a distinctive style. In 1986 Andy Warhol was one of the first to recognise the paradoxical nature of the look and language of camouflage in a series of works simply titled Camouflage, which drew attention to the way in which camouflage is intended to blend-in and disappear, yet it does the complete opposite by being immediately recognisable.

Camouflage is now common place in the fabric of visual culture. According to Vogue, alongside checked print, camouflage print is making a fashion comeback in the Fall/Winter 2020-2021, something that Adidas may have hinted at a few years earlier when it launched the X15 Eskolaite; a bold Soccer boot which combines metallic silver and a bright green like the rare camouflaging mineral this boot owes its name to, both dazzling and blending in the field.

Artists use Chromium Green Oxide because it is very good at making a wide range of greens when mixed with other colours, making it as important to the artist today as it was when it was unveiled as a new colour 170 years ago in Paris. You can find this green colour name in our Professional Acrylic range, but it is called Oxide of Chromium in Artists’ Oil Colour, Winton, Griffin Alkyd, Professional Watercolour and Gouache.