19th century painters had a new range of pigments to choose from due to the invention of synthetic pigments – chemically synthesised in the laboratory – around 1800. Almost exactly one half of the pigments that made up the palettes of the French Impressionist painters were synthetics, the others being the historical pigments. The palettes of Cézanne, Manet, Monet, Pissarro, Renoir, Signac, Seurat and Van Gogh are given in this little book.
In their investigations into light, several scientists – James Clerk Maxwell, Ogden Rood – compared the measurements of the wavelengths of colours in a band of prismatic light with certain painters’ pigments to discover their similarity. As the human eye is also a prism, the correspondence was determined: the colours the eye sees are the colours of light and, by extension, selected pigment colours could capture light exactly. The French Impressionist painters seized on this reality and began to paint light with their new “solar palettes”.
These discoveries are presented by the Editor in this collection of short texts by scientists and painters.
I• Plates –
1 • M. E. Chevreul, Chromatic Circle of Hues 2 • French edition 3 • M. E. Chevreul, Optical Complementary Colours 4 • H. v. Helmholtz, Prism Spectrum of Sunlight with Corresponding Pigment Swatches; Van Gogh’s Palette 5 • J. C. Maxwell, Primary Colours of Light 6 • The Brushstroke
III• “Our Studies of Light” – 1• Complementary Colours Combine to White Colourless Light in the Spectrum and to Luminosity in the Eye; 2• On the Mixing of Light and on Optical Mixing; 3• Prismatic-Pigment Correspondences; 4• From Sunrise to Sunset
IV• Complementary Colours Combine to White Colourless Light in the Spectrum and to Luminosity in the Eye
Texts by M. E. Chevreul
V• On the Mixing of Light and on Optical Mixing
Texts by Ogden N. Rood
VI• Prismatic- Pigment Correspondences According to
Hermann von Helmholtz and Ogden Rood
Texts by Hermann von Helmholtz and Ogden N. Rood
VII• Palettes of the Solar Spectrum
P. Cézanne, E. Manet, C. Monet, C. Pissarro, P.-A. Renoir, G. Seurat, P. Signac, V. van Gogh
VIII• Pigments of the Solar Palette – Descriptions
IX• Plates – Pigments of the Solar Palette – Colour Swatches
PIGMENTS OF THE SOLAR PALETTE
All the pigments are Synthetic unless otherwise indicated
Alizarin red lake
Carmine – Artificial, animal
Rose madder – Vegetable and Synthetic
Red ochre – Natural
Vermilion and Cinnabar – Artificial and Natural
Cadmium yellow orange
Chrome yellow orange
Gamboge – Natural
Minium or Red Lead – Artificial
Cobalt yellow, called Aureolin
Litharge – Artificial
Naples yellow – Artificial
Siennas and Umbers – Natural
Brunswick green – Natural and Mixed
Chromium oxide green
Cobalt green – compound pigment mixture
Emerald Green, Scheele’s Green, Schweinfurt Green,
Terre verte / Green earth – Natural
Viridian, Vert emeraude
Cyan Blue identified as Prussian Blue
Indigo – Artificial, plant
Ultramarine – Natural and Artificial
Ivory black – Artificial, plant
Lamp black – Artificial, plant
Peach black – Artificial, plant
Silver white / blanc d’argent
Contribution of the Impressionists
From Eugene Delacroix to Neo-Impressionism
Paragraphs 1 to 5
Translated by Patricia Railing
Impressionism – Art & Optics of Light
Contribution of the Impressionists
Jongkind, precursor, Renoir, Monet, Pissarro.
Guillaumin, Cézanne, Sisley.
At the beginning they were influenced by Courbet and Corot. Turner brought them back to Delacroix.
The simplified palette.
Pure colours are dulled by mixtures.
The sensation and the method.
1. After Delacroix, those who will be the champions of colour and of light are the painters who later were called the Impressionists: Renoir, Monet, Pissarro, Guillaumin, Sisley, Cézanne and their admirable precursor, Jongkind.
The latter was the first to reject the flat hue, break up his colour, fragment his strokes ad infinitum, and who obtained the finest colourings in the combinations of many and almost pure elements.
At this time those who would be Impressionists were influenced by Courbet and Corot, apart from Renoir who came instead from Delacroix after whom he made copies and interpretations. They were still painting in large areas, flat and undefined, and seemed to be exploring white, black and grey rather than pure and vibrant colours, while Fantin Latour, the painter of the Homage to Delacroix and so many other serious or serene works, draws and paints with hues and tones which, even if not intense, at least they were graded and separated. But in 1871 during a long sojourn in London, Claude Monet and Camille Pissarro discovered Turner. They marvelled at the magic and enchantment of his colouring. They studied his works, analysing his craft. They were especially struck by his effects of snow and ice. They were astonished by the way in which he succeeded in giving a sensation of the whiteness of snow, they who until then had not been able to achieve this in the use of large patches of silver white [pigment] spread out flatly using large brush strokes. They noticed that this marvellous result was obtained not by a unified white but by many strokes of various colours set next to each other and which at a distance reconstituted the desired effect.
This method of using multicoloured strokes – which they first noticed in the effects of snow because they were surprised at not seeing it represented using white and grey as was the custom – they then found was used in the most intense and brightest paintings by the English artist. It is thanks to this device that these canvases appear to be painted not with ordinary paints but with ethereal colours.
2. Returning to France and absorbed by their discovery, Monet and Pissarro joined Jongkind who was then fully in possession of his effective craft which allowed him to interpret the most fleeting and most subtle plays of light. They noticed the analogy of his methods with those of Turner. They understood all the benefits that could be drawn from the purity of the one and the texture of the other. Little by little, the blacks and earth [pigments] disappeared from their paintings and soon they began to decompose the hues and reconstitute them on the canvas in tiny flecks, which they juxtaposed.
From the undeniable influence that Turner and Jongkind were having on them the Impressionists were thus brought back to Delacroix’s technique, from which they had distanced themselves in order look for an application in the oppositions of white and black. For is not the fleck in the Impressionist painting like the hatchings in Delacroix’s large decorative panels reduced to the proportion of small format canvases to which the work after nature is subject? It is the very same method they all employed in order to obtain the same goal: light and colour.
Jules Laforgue aptly remarked on this descendent:
“The vibrancy of the Impressionists using a thousand dancing flakes. Marvellous discovery foreshadowed by the madness of movement, Delacroix who, in the cold furies of romanticism and not satisfied by violent and wild movements of colour, modelled with vibrant hatchings.”
3. But while Delacroix used a complex palette made up of pure colours and earth colours, the Impressionists used a simplified palette composed of seven or eight of the brightest colours which were closest to those of the solar spectrum. As of 1874 Monet, Pissarro, Renoir – who was the first? it doesn’t matter – had on their palettes only yellows, oranges, vermilions, lakes, reds, violets, blues, and intense greens such as emerald and viridian.
This simplification of the palette, which gave them a very limited range of colours, forced them to decompose the hues and to multiply the elements. They made every effort to reconstitute the colourings by an optical mixing of the innumerable multicoloured flecks that were juxtaposed, criss-crossed and intermingled.
4. Taking advantage of these new means – decomposition of the tones and exclusive use of saturated colours – they could paint the landscapes of the Ile-de-France or of Normandy and make them much brighter and more luminous than Delacroix’s oriental scenes. For the first time one could admire landscapes and figures that were truly sunlit. No longer needed was the bituminous and dark foreground which served as a foil for their predecessors – even for Turner – in order to make the background appear luminous and coloured.
The entire surface of the painting was resplendent with sunlight. Air circulated, light enveloped, wafted around and radiated the forms, penetrating everywhere even in the shadows that it illumined.
Fascinated by the enchantments of nature, the Impressionists, thanks to a quick and assured execution, became able to fix the animation of these scenes. They are the glorious painters of fleeting effects and momentary impressions.
 [Signac uses “le véronèse et l’émeraude”, terms that are often confused in translations, even in the 19th century. Vert Véronèse is copper arsenate, called emerald green in English. Vert émeraude is viridian in English, chromium oxide dihydrate, the original chromium oxide green discovered in 1838 by Pannetier, a Paris colour maker, then developed and patented in 1859 by Guignet. Ed.]
 [By “their predecessors” Signac is referring to the Barbizon painters known as the school of 1830, their landscapes described by a writer who understood and defended Impressionism, Edmond Duranty. In 1/1876, The New Painting, herein) he wrote, “The Romantic artist, in his studies of light, knew nothing but the orange-tinted band of the setting sun over sombre hills, or the white impasto tinged with chrome yellow or rose madder which he threw across the opaque bitumen of his woods. No light could exist without bitumen, without ivory black or Prussian blue, without the contrasts that were said to make the tone appear warmer, to heighten it. He believed that light coloured and awakened tone and was persuaded that it could not exist unless surrounded by shadow.” Ed.]
Van Gogh’s “Practical Palette” 1882
Reading the palette from right to left, Vermilion, Ivory black, Cobalt blue, Raw Sienna, Burnt ochre, Red ochre, Yellow ochres, Naples yellow, Silver white.