I’m currently reading Bright Earth: The Invention of Colour

This is a fascinating book about colour – from many different perspectives. I am highlighting quotes as I go – but there are SO many points of interest for me that I could quote the whole book! So I am going to quote these in chunks.

The first four chapters are: 1. The Eye of the Beholder THE SCIENTIST IN THE STUDIO; 2. Plucking the Rainbow THE PHYSICS AND CHEMISTRY OF COLOUR; 3. The Forge of Vulcan COLOUR TECHNOLOGY IN ANTIQUITY; 4. Secret Recipes ALCHEMY’S ARTISTIC LEGACY

The starting point is the study of colour and its effects on men. Wassily Kandinsky , Concerning the Spiritual in Art (1912)

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 204-206). Random House. Kindle Edition.

‘I BELIEVE THAT in future, people will start painting pictures in one single colour, and nothing else but colour.’ The French artist Yves Klein said this in 1954, before embarking on a ‘monochrome’ period in which each work was composed from just a single glorious hue . This adventure culminated in Klein’s collaboration with Paris paint retailer Edouard Adam in 1955 to make a new blue paint of unnerving vibrancy .

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 217-221). Random House. Kindle Edition.

‘Praise be to the palette for the delights it offers . . . it is itself a “work”, more beautiful, indeed, than many a work,’ said Wassily Kandinsky in 1913.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 232-233). Random House. Kindle Edition.

Van Gogh dispatched his brother to acquire some of the brightest and most striking of the new pigments available, and wrought them into disturbing compositions whose strident tones are almost painful to behold. Many were dumbfounded or outraged by this new visual language: the conservative French painter Jean-Georges Vibert rebuked the Impressionists for painting ‘only with intense colours’.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 238-241). Random House. Kindle Edition.

When Titian, Henry James’s ‘prince of colourists’, took advantage of having the first pick of the pigments brought to the thriving ports of Venice to cover his canvases with sumptuous reds, blues, pinks and violets, Michelangelo remarked sniffly that it was a pity the Venetians were not taught to draw better.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 242-245). Random House. Kindle Edition.

Faber Birren admits in his classic History of Color in Painting that ‘the choice of colours for a palette or palettes is not in any way concerned with chemistry, or with permanence, transparency, opacity or any of the material aspects of art’. This extraordinary omission of the substantial dimension of colour is surely the precondition for such absurdities as Birren’s assigning cobalt blue to the palette of Rubens and his contemporaries, almost two centuries before its invention.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 262-265). Random House. Kindle Edition.

Bridget Riley, one of the modern artists most concerned with colour relationships, has expressed the dilemma very clearly: For painters, colour is not only all those things which we all see but also, most extraordinarily, the pigments spread out on the palette, and there, quite uniquely, they are simply and solely colour. This is the first important fact of the painter’s art to be grasped. These bright and shining pigments will not, however , continue to lie there on the palette as pristine colours in themselves but will be put to use – for the painter paints a picture, so the use of colour has to be conditioned by this function of picture making . . . The painter has two quite distinct systems of colour to deal with – one provided by nature, the other required by art – perceptual colour and pictorial colour. Both will be present and the painter’s work depends upon the emphasis they place first upon the one and then upon the other.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 269-276). Random House. Kindle Edition.

Riley’s formulation of the artist’s situation. Pigments are not ‘simply and solely colour’, but substances with specific properties and attributes, not least amongst them cost. How is your desire for blue affected if you have just paid more for it than for the equivalent weight in gold? That yellow looks glorious, but what if its traces on your fingertips could poison you at your supper table? This orange tempts like distilled sunlight, but how do you know that it will not have faded to dirty brown by next year? What, in short, is your relationship with the materials?

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 278-282). Random House. Kindle Edition.

Use of colour in art is determined at least as much by the artist’s personal inclinations and cultural context as by the materials to hand.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 289-290). Random House. Kindle Edition.

Every choice an artist makes is an act of exclusion as well as inclusion.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 291-292). Random House. Kindle Edition.

each artist makes his or her own contract with the colours of the time.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 293-294). Random House. Kindle Edition.

Until the eighteenth century, most artists ground and mixed their own pigments, or at least had this process conducted in their studios.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 304-305). Random House. Kindle Edition.

In stressing the importance of science in art, Leonardo had an agenda that was very much a product of its time. By emphasizing the role of mathematics, he attempted to elevate the status of painting to a Liberal Art, alongside geometry, music, rhetoric and astronomy. These Arts were those deemed worthy of serious intellectual study at the universities, whereas painting had been regarded since the Middle Ages as a craft, a lowly manual skill. Such activities in the classical past had often been performed by slaves, and painters of Leonardo’s time were desperate to throw o? this stigma. By arguing for the acceptance of painting as a Liberal Art, they sought to advance their own social standing.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 320-325). Random House. Kindle Edition.

The artist’s cause demanded that artists dissociated themselves from craftsmen , and allied their skills with mathematics and abstract thought.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 336-337). Random House. Kindle Edition.

Thus did art begin to fragment into the ‘pure’ and the ‘applied’, a distinction not seriously challenged until the nineteenth century. In The Two Paths (1859), John Ruskin deplored art’s own ‘two cultures’ and argued that decorative art and craft should not be regarded as ‘a degraded or separate kind of art’.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 346-348). Random House. Kindle Edition.

Unusually among artists, students of ceramics are one group who still have to learn some real chemistry

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 382-383). Random House. Kindle Edition.

The truth – a dirty truth, if you will – is that new colours for artists have long been a by-product of industrial chemical processes that reach out to a much wider market .

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 389-390). Random House. Kindle Edition.

Artificial copper blues or ‘verditers’, the principal cheap alternatives to expensive blue pigments from the fifteenth to the eighteenth century, were a side-product of silver mining. They were largely replaced by Prussian blue, produced primarily for the massive textile dyeing industry rather than for the tiny market in artists’ colours. The Mars colours (artificial iron oxides) could not have been made without the availability of cheap sulphuric acid, which was manufactured primarily as a textile bleach. The pigment known as patent yellow was an offshoot of the soda industry, while the manufacture of chrome yellow was stimulated by its use in cotton printing.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 391-396). Random House. Kindle Edition.

The almost ubiquitous white pigment of the twentieth century, titanium dioxide, is produced almost entirely for commercial paints – the amount diverted to artists’ materials is trivial.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 397-398). Random House. Kindle Edition.

But aren’t naked pigments already works of art – the products of skill and creativity, and substances of glorious elegance and splendour?

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 400-401). Random House. Kindle Edition.

The modern chemicals industry was spawned and nurtured largely by the demand for colour. Important advances in synthetic chemistry in the nineteenth century were stimulated by the quest for artificial colours .

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 403-405). Random House. Kindle Edition.

Many of the world’s major chemicals companies – BASF, Bayer, Hoechst, Ciba-Geigy – began as manufacturers of synthetic dyes. And the reproduction of art and colour in photography and printing has given rise to major technological companies such as Xerox and Kodak.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 405-407). Random House. Kindle Edition.

German chemistry Nobel Laureate Wilhelm Ostwald worked with the German paint industry in the 1920s, and his theory of colour was hotly debated at the Bauhaus where Klee and Kandinsky taught.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 408-410). Random House. Kindle Edition.

Chemical science and technology and the use of colour in art have always existed in a symbiotic relationship that has shaped both their courses throughout history.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 411-412). Random House. Kindle Edition.

Yves Klein invites us to engage with the beauty of raw colour. This goes against our training.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Location 415). Random House. Kindle Edition.

colour threatens us with regression, with infantilism.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Location 416). Random House. Kindle Edition.

Cultural theorist Julia Kristeva claims that ‘the chromatic experience constitutes a menace to the “self” . . . Colour is the shattering of unity.’ 12 What else is coloured? Vulgar things, vulgar people. Colour speaks of heightened emotions, even linguistically, and of eroticism.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 416-419). Random House. Kindle Edition.

Le Corbusier asserted that colour was ‘suited to simple races, peasants, and savages’.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 419-420). Random House. Kindle Edition.

The nineteenth-century art theorist Charles Blanc (what’s in a name?) insisted that ‘design must maintain its preponderance over colour. Otherwise painting speeds to its ruin: it will fall through colour just as mankind fell through Eve.’ 14 Here, then, is another reason to distrust colour: it is feminine.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 424-427). Random House. Kindle Edition.

To the chemist, colour is a bountiful clue to composition and, if measured carefully enough, can reveal delicate truths about molecular structure.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 438-439). Random House. Kindle Edition.

Before we can adequately explore what colour means to the artist, we must ask what we mean by colour itself. This might seem uncontentious enough. In spite of the old solipsism that I can never know if my experience of ‘red’ is the same as yours, we both agree when the term is appropriate and when it is not.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 447-449). Random House. Kindle Edition.

the language of colour reveals much about the way we conceptualize the world. Linguistic considerations are often central to an interpretation of the historical use of colour in art.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 450-452). Random House. Kindle Edition.

The Latin caeruleum carries a similar ambiguity between yellow and blue (its root is the Greek kuanos, which can in some contexts denote the dark-green colour of the sea).

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 462-463). Random House. Kindle Edition.

How could red and green ever be conflated? From a modern-day perspective this appears absurd, because we have in our minds Isaac Newton’s rainbow spectrum and its corresponding colour terminology , with its seven bands firmly delineated. The Greeks sawadifferent spectrum, with white at one end and black at the other – or more properly, light and dark. All the colours lay along the scale between these two extremes, being admixtures of light and dark in different degrees. Yellow was towards the light end (it appears the

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 464-469). Random House. Kindle Edition.

The confusion of blue and yellow may have been purely linguistic, or it may have its origin in the naming of colours after the materials that supplied them ( see here ). For reasons that are far from clear, blue and yellow are categorized together in many languages and cultures, including some Slavic tongues, the Ainu language of northern Japan, the Daza language of East Nigeria and that of the Mechopdo Native Americans in northern California. The Latin flavus, meaning yellow, is the etymological root of blue, bleu and blau.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 471-475). Random House. Kindle Edition.

whether or not an artist considers two hues to be different colours or variants of the same colour is largely a linguistic issue.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 477-478). Random House. Kindle Edition.

As there are no culture -independent concepts of basic colours, it seems impossible to establish a universal basis for a discussion of colour use.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 481-482). Random House. Kindle Edition.

Colour vocabulary, they said, unfolds in a strict sequence.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 488-489). Random House. Kindle Edition.

Hanunoo, which is spoken by a Malayo -Polynesian people in the Philippines, has four colour terms: ‘dark’ and ‘light’, which we can equate readily enough with black and white; but also ‘fresh’ and ‘dry’ (in so far as they can be matched with English words at all). Some prefer to ally these two with green and red, but they seem to allude to texture as much as to hue. There is no Hanunoo word

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 490-493). Random House. Kindle Edition.

Wittgenstein voiced the same idea in his Remarks on Colour: ‘Mightn’t shiny black and matt black have different colour names?’ (In his black monochromes of the 1960s the American minimalist artist Ad Reinhardt used these two as if they were indeed distinct colours.)

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 511-513). Random House. Kindle Edition.

Linguist John Lyons suggests it is safest to conclude only that colours ‘are the product of language under the influence of culture’. The fluidity of colour terminology led to a frequent reliance on materials, rather than abstract concepts of hue, as the basis of a discussion about artists’ use of colour.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 517-519). Random House. Kindle Edition.

Without a secure theoretical basis for classification, talk of colour needs to be rooted in the physical substances that provide it. Yet this simply creates fresh scope for ambiguity, for the substance can mutate into a colour term in its own right. Scarlet, for example, was once a kind of medieval dyed cloth, which need not have been red at all.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 521-523). Random House. Kindle Edition.

It is tempting to regard modern and abstract painters as the first consciously to decide that they would not simply try to paint ‘what they saw’. Yet the most casual of glances at any image from the Renaissance or the Baroque period shows how much the work is guided by certain conventions, and at the same time by imagination and interpretation, rather than being an attempt to depict nature as faithfully as possible.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 524-527). Random House. Kindle Edition.

For example , until the late nineteenth century, using colour to mimic nature was necessarily an artifice in at least this respect: nearly all paintings were produced in studios with reliance on the painter’s judgement about ‘proper’ composition and contrast. It was only when painting of finished works (as opposed to reference studies) out of doors was pioneered by the French Realists , and later adopted by the Impressionists, that artists began to liberate themselves from academic notions about light and shade, to see the purples and blues in shadows, the yellows and oranges in ‘white’ sunlight.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 528-532). Random House. Kindle Edition.

‘One who haphazardly throws around even the most beautiful colours’, said Aristotle, ‘cannot delight the eye as one who has drawn a simple figure against a white background.’ Moreover, Classical art was not slavishly imitative, but largely symbolic. Pliny’s four-colour scheme was linked more closely to metaphysics than to any relation with the hues of nature, which on a fine day in the hills of Greece would be saturated with the very colours – green and blue – that the scheme omits.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 536-540). Random House. Kindle Edition.

‘mixing produces conflict ,’ said Plutarch in the first century AD. It was common to refer to the blending of pigments as ‘deflowering’: a loss of virginity. Aristotle called colour-mixing a ‘passing away’.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 543-544). Random House. Kindle Edition.

But there was also a technical inhibition towards mixing. Because the available pigments were not pure primary colours, mixing resulted in a diminution of tone towards greyness or brownness, and so was indeed a degrading process. This reluctance to mix pigments might explain some of the curious claims about painting made in the Classical literature , which would readily have been disproved by experiment: that red and green could generate yellow, or that (as Aristotle suggested ) no pigment mixture could generate violet or green. Greek painters were prepared to glaze a translucent colour over an opaque one, but mixing ‘on the palette’ was usually restricted to the use of white or black for highlights and shadows.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 545-550). Random House. Kindle Edition.

– it became desirable to display the most costly and wonderful pigments in flat, unbroken fields of colour:

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 557-560). Random House. Kindle Edition.

Leon Battista Alberti discusses juxtapositions of colour almost as if arranging a series of coloured wooden blocks – or in this case, the robes of a series of nymphs: If red stands between blue and green, it somehow enhances their beauty as well as its own. White lends gaiety, not only when placed between grey and yellow, but almost to any colour. But dark colours acquire a certain dignity when between light colours, and similarly light colours may be placed with good effect among dark. 20 There is in this advice a hint of the ideas about colour harmony that were to recur throughout artistic theory from the Renaissance to the twentieth century.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 563-569). Random House. Kindle Edition.

Alberti betrays an abiding concern with the integrity of the pure pigment – with preserving the raw colour and avoiding practices that would muddy it or degrade its brilliance. Highlight and shadow, he advises, should be rendered simply by adding white and black – and with great restraint, lest the virtue of the colour be degraded: Those painters who use white immoderately and black carelessly, should be strongly condemned. It would be a good thing if white and black were made from those pearls Cleopatra dissolved in vinegar, so that painters would become as mean as possible with them, for their works would then be both more agreeable and nearer the truth. 21 Here ‘truth’ means true to the glory of the materials rather than capturing what nature reveals to the eye.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 571-578). Random House. Kindle Edition.

Theosophy appealed also to the Dutch painter Piet Mondrian (1872– 1944), whose efforts to arrange rectangles of primary colours on a heavy black grid evoke a kind of mathematical angst. He was an advocate of the Theosophist M. H. J. Schoenmaekers, who argued that all colours except the three primaries were superfluous – providing Mondrian with his own distinctive answer to the problem of colour.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 600-603). Random House. Kindle Edition.

Kandinsky’s conviction that colour acts as a universal language of the soul. Of course , colour does speak to our emotions – but not, it seems , in a way that everyone agrees on, independent of cultural conditioning. Yet Kandinsky believed there are concrete, objective colour associations, so that an abstract composition can, through the calculated use of colour, invoke a very particular emotional response.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 603-607). Random House. Kindle Edition.

Concerning the Spiritual in Art (1912), where we find such claims as this: Yellow is the typical earthly colour. It can never have profound meaning. An intermixture of blue makes it a sickly colour . . . Vermilion is a red with a feeling of sharpness, like glowing steel which can be cooled by water . . . Orange is like a man, convinced of his own powers . . . Violet is . . . rather sad and ailing.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 612-615). Random House. Kindle Edition.

Kandinsky’s fruitless search for the emotional

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 624-627). Random House. Kindle Edition.

Bridget Riley, it is precisely this that makes colour so powerful a medium of artistic expression: . . . just because there is no guiding principle, no firm conceptual basis on which a tradition of colour painting can be reliably founded, this means that each individual artistic sensibility has a chance to discover a unique means of expression.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 628-631). Random House. Kindle Edition.

There is no such thing as colour, only coloured materials. Jean Dubuffet (1973)

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 635-636). Random House. Kindle Edition.

Inorganic nature has only the language of colour. It is by colour alone that a certain stone tells us it is a sapphire or an emerald. Charles Blanc , Grammar of Painting and Engraving (1867)

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 637-640). Random House. Kindle Edition.

What is paint after all? Colored dirt. Philip Guston

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 641-642). Random House. Kindle Edition.

This is an example of light scattering, which is the major physical way in which colour can be produced. Light absorption, in contrast , depends on the chemical composition of the substance. As light enters a raindrop, the ray is bent (refracted). The angle of bending depends on the wavelength of the light, being sharper for shorter wavelengths. So blue light is deflected more than red light, and the various colours in sunlight are unravelled. Each colour reaches your eye from a slightly different region in the rainbow’s arc. The scattering of light can therefore separate colours according to their wavelength. The sky is blue because blue light is scattered by the molecules and dust in the atmosphere more strongly than red light, and so seems to come from all directions. Distant hills acquire a blueness for the same reason: the reflected light is augmented by the omnidirectional blue before reaching the eye. (In art this blueing of distant landscape, described by Leonardo, is called aerial perspective.) As the sun sinks low in the sky, its rays travel through a thicker slice of the atmosphere before reaching the observer, and the blue component of the light may be scattered so strongly that it never gets to the eye.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 715-723). Random House. Kindle Edition.

Natural pigments obtain their colours by absorption of light. But some colours in nature result from physical scattering processes. In particular, no vertebrate animals contain blue pigments: their blue markings are produced by light scattering. The blues on butterfly wings are the result of a microscopic ribbed structure of individual scales on the wing ( Figure 2.2 ). These ridges have a spacing that induces preferential scattering of blue light. But the scattering, and thus the hue, varies somewhat depending on the angle

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 728-733). Random House. Kindle Edition.

a Byzantine writer of the seventh century AD asked: How could anyone who sees the peacock not be amazed at the gold interwoven with sapphire, at the purple and emerald-green feathers, at the composition of the colours of many patterns, all mingled together but not confused with one another?

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 736-738). Random House. Kindle Edition.

Ground-up stained glass becomes paler with prolonged grinding: smaller particles have a greater total surface area to scatter from, and so scattering (which is indiscriminate about wavelength across the visible range) dominates over absorption (which picks out certain wavelengths) . This is why grinding a coloured powder may affect its hue

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 747-749). Random House. Kindle Edition.

Ask a chemist to assign colours to the most common transition metals and he or she will know the game at once. Red is for iron, resplendent in blood and rust and the red ochres daubed by painters since the Stone Age. Copper claims for itself the turquoise shade associated with that mineral and which is echoed in the greenish patina of ageing copperwork. Rich, deep blue stands for cobalt, and nickel takes a sea-green; while chromium provokes some hesitation, an elemental chameleon and named for it too. These are not rigid identities – copper, for instance, can form rust-red salts, and iron offers greens and yellows, even the dark lustre of Prussian blue.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 757-762). Random House. Kindle Edition.

One hazard of vermilion is that its constituent ions can reshuffle from their usual positions to new locations in a form of the compound called metacinnabar. This absorbs red light as well as blue and green, and so it appears black – fatal, of course, if it happens on the canvas.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 798-800). Random House. Kindle Edition.

metals like copper and gold do absorb some of the short-wavelength (bluish) rays that strike them, and so they take on a reddish tinge. To medieval artists, this allied pure gold leaf with red pigments.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 803-804). Random House. Kindle Edition.

Tyrian purple, the imperial colour of Rome, was drawn out of shellfish. Blue indigo was the frothy extract of a weed. Madder red came from a root, cochineal from an insect. Today virtually all dyes are synthetic organic molecules, their carbon skeletons custom-built by industrial chemists.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 809-811). Random House. Kindle Edition.

because light passing from air to rock at the surface of a dry pebble experiences a greater change in refractive index than light passing from water to rock when the pebble is wet, more of it is scattered rather than being reflected directly to our eye. This makes the dry pebble look paler and chalkier than the wet pebble.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 834-837). Random House. Kindle Edition.

Sadly, the same effect can undo the bright promise of pigments: glorious as dry powders, they might become dark or semitransparent when mixed with a binding agent such as linseed oil. This degradation of brilliance when a pigment meets the liquid medium of a paint is what dismayed Yves Klein and led him on his chemical quest for a new binder that honoured the vibrancy of the raw pigment.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 837-839). Random House. Kindle Edition.

The principal binding media before the fifteenth century were water (in frescos), gum or egg white (in manuscript illumination ) and egg yolk (in tempera painting on panels). When artists began to use oils, which have a higher refractive index, they found that some of their most treasured pigments were no longer so beautiful. Ultramarine is darker, vermilion less opaque, chalk white is almost transparent. Other changes were for the better. In oils, translucent colours such as red lakes become not only more transparent but warmer, and give rich results when glazed in thin layers over other colours.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 839-844). Random House. Kindle Edition.

colour depends on the circumstances under which we look for it. There is a sense in which we can regard leaves as possessing

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 854-857). Random House. Kindle Edition.

It was not until the seventeenth century that the three modern primaries – red, yellow and blue – became established.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 887-888). Random House. Kindle Edition.

In terms of physics, the colour wheel is a wholly artificial device, since the light that it denotes increases in frequency from red to violet before leaping across a discontinuity back to red.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 899-900). Random House. Kindle Edition.

But the wheel organizes colour space into a pleasingly symmetrical pattern in which primaries and secondaries alternate with their mixing relationships clearly defined. This is not, however, quite how Newton saw it: he awarded no particular prominence to the hues we now regard as primary, and his wheel was a seven-spoked affair of unequal slices ( Figure 2.3 ). Subsequent colour theorists tended to emphasize the symmetry ( Figure 2.4 ). Even if there was not total agreement over the number of subdivisions , the colour wheel became iconic within the colour theories of the nineteenth and early twentieth centuries, and few artists were unfamiliar with this emblematic representation of the territory they negotiated. One of the most impressive colour wheels was that published by the French theorist and chemist Michel-Eugène Chevreul in his book Des couleurs et de leurs applications aux arts industriels (1864 ). Here the smooth gradations from one colour to the next ( Plate 2.1 ) stretched the contemporary colour-printing technology to its limits, and the printer, M. Digeon, won an award for the work from the French Société d’Encouragement pour l’Industrie Nationale. It was well deserved: the original wheel looks as stunning as ever today.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 900-910). Random House. Kindle Edition.

By blending light rays of different wavelengths, one is synthesizing colour by the addition of various components, which together stimulate the retina in the eye to create a particular colour sensation. This is called additive mixing.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 919-921). Random House. Kindle Edition.

A blend of pigments, on the other hand, subtracts wavelengths from white light. That is to say, the pigments themselves are not the sources of the light that triggers a colour sensation, but are media that act on a separate source of illumination. A red pigment plucks out the blue and green rays, and much of the yellows; only red light is reflected.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 931-934). Random House. Kindle Edition.

making colours by mixing pigments is called subtractive mixing.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 938-939). Random House. Kindle Edition.

Subtractive mixing inevitably penalizes the luminosity of the pigments, since more of the illumination is absorbed by the mixture. For example, most red and yellow pigments inevitably absorb a little orange light. So the orange that results from their mixture isn’t very brilliant – some of the orange light is lost from the white light that illuminates the image. In contrast, a genuine orange pigment absorbs virtually no light in the ‘orange’ part of the spectrum and so doesn’t suffer from this defect. This is why a genuine orange pigment may be more vibrant than a mixture of red and yellow.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 939-943). Random House. Kindle Edition.

Goethe recognized that strong hues tend to generate an impression of their complementary colour in the surrounding field, like a contrasting halo. The same effect arises in the ‘after-image’ produced when one stares at a colour for long moments and then looks away.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 957-959). Random House. Kindle Edition.

‘Every decided colour does a certain violence to the eye, and forces it to opposition,’ he suggested, more or less correctly. It is for the same physiological reason that a colour looks more vivid if juxtaposed with its complementary: the two colours mutually enhance one another, and generate a kind of vibration at their interface. This idea was to become central to the thinking of all colouristically inclined artists in the nineteenth century, particularly the Impressionists.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 964-967). Random House. Kindle Edition.

Of different colours equally perfect, that will appear most excellent which is seen near its direct contrary . . . blue near a yellow, green near red: because each colour is more distinctly seen when opposed to its contrary, than to any other similar to it.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 970-972). Random House. Kindle Edition.

Maxwell gave his weighty endorsement to this suggestion: ‘The science of colour must . . . be regarded as essentially a mental science.’

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 976-977). Random House. Kindle Edition.

The differing colour sensitivity of rods and cones results in a change in the perceived intensity of blue/ green objects relative to red as twilight deepens.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1009-1010). Random House. Kindle Edition.

The blue-light cones are the least sensitive, which is why fully saturated blue looks relatively dark. Blue’s late historical arrival as a true colour, as opposed to a kind of black, is thus ultimately for biological reasons.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1013-1015). Random House. Kindle Edition.

The yellow band in a rainbow stands out not because it is more intense (not, that is, because there are more yellow photons than others) but because the yellow photons generate the biggest optical response from the eye. Curiously, yellow is regarded in many cultures as the least attractive colour, and its metaphorical and symbolic associations are often denigrating. It is traditionally the shade of treachery and cowardice, and clothing designers admit that it is a terribly difficult colour to sell.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1017-1020). Random House. Kindle Edition.

Red light excites mostly the ‘red’ cones. But a mixture of red and green rays can stimulate red and green cones in the same ratio as does pure yellow light – and so the colour sensations are identical. If blue light is added, we see white. (Although the three types of cone are often linked to Maxwell’s primaries of red, green and blue, this is a crude shorthand. Their peak sensitivities are in fact in the yellow, green and violet repectively.)

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1022-1025). Random House. Kindle Edition.

What, then, is grey? Along with black and white, grey is sometimes classified as an oxymoronic ‘achromatic colour’ – we might say that grey has no ‘colour’ as such, but is more of an intermediary between light and dark. Grey is what we perceive when all wavelengths are absorbed partially, yet more or less equally , from white light. It is, if you will, white light with the volume turned down.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1048-1051). Random House. Kindle Edition.

Brown is in fact a kind of grey biased towards yellow or orange. A brown surface absorbs all wavelengths to some extent, but orange/ yellow somewhat less than others. Another way of saying this is that brown is a low-brightness yellow or orange,

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1052-1054). Random House. Kindle Edition.

The CIE diagram shows just two of the three parameters of colour – two ‘dimensions’, portrayed on a flat plane. One of these is hue, which is what we usually mean colloquially by ‘colour’. Strictly speaking, the hue is the dominant wavelength in the colour, and it is what enables us to characterize a colour as basically red, green or whatever. In this sense, the hue of brown is yellow or orange, while grey has no hue – no dominant wavelength – and so can be regarded as achromatic.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1059-1063). Random House. Kindle Edition.

in English and most other European languages there is still no generally accepted colour term for the hue between yellow and green, or that between green and blue, even though these occupy appreciable parts of the perimeter.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1065-1066). Random House. Kindle Edition.

Painters need colour to be embodied in stuff, they need to be able to purchase it and get it smeared across their overalls. That is the bottom line, and I would not like to see it obscured (as sometimes it has been) among multi-hued wheels and globes and charts. Painters need paint. Colour is their medium of expression and communication, but to make their dreams visible it needs substance.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1100-1103). Random House. Kindle Edition.

pigment manufacture in antiquity was an offshoot of a large and thriving chemical industry that transformed raw materials into the substances needed for daily life.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1213-1214). Random House. Kindle Edition.

During the fifth century BC the Greek artists began to paint three-dimensionally, using a chiaroscuro (‘ highlight and shadow’) technique to depict depth. This development might have motivated the four-colour technique as a means of bringing colour under control while artists worked out how to manage light and dark. As Renaissance artists were to discover, the larger the palette, the more difficult it is to achieve harmony of hue and tone so that no one colour stands out jarringly from the others. By restricting the range of hues, and moreover by rendering them in low-keyed earth pigments rather than bright ones, it becomes easier to master a three-dimensional world of light and shadow.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1472-1477). Random House. Kindle Edition.

Yet pure, bright colours were not shunned in the decorative arts. They were used by the Greeks to adorn buildings,

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1481-1482). Random House. Kindle Edition.

Sometimes the past is too fragile to bear our gaze.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Location 1538). Random House. Kindle Edition.

Cennino assumes that the artist knows what he means by the instruction that plaster should be made as if preparing batter.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1821-1822). Random House. Kindle Edition.

To qualify as a ‘master painter’ ready to accept contracts, an apprentice would present a ‘master piece’ to the guild for approval. Strange, then, that this term has come to refer to an artist’s most accomplished piece of work rather than his or her first attempt to gain recognition.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1850-1852). Random House. Kindle Edition.

To qualify as a ‘master painter’ ready to accept contracts, an apprentice would present a ‘master piece’ to the guild for approval. Strange, then, that this term has come to refer to an artist’s most accomplished piece of work rather than his or her first attempt to gain recognition.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1850-1852). Random House. Kindle Edition.

most of the large-scale paintings of the Middle Ages that are still in existence are rendered on wood, carved and ornamented and often joined into two or more hinged panels in a polyptych. The wood was coated first with size and then with several layers of gesso,

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1875-1877). Random House. Kindle Edition.

Egg tempera is relatively quick-drying, and so the artist must work swiftly, especially when blending colours. Dry, aged egg tempera paint is virtually waterproof and, if skilfully prepared, discolours less rapidly than oil paints. Some of the colours inmedieval tempera panels are more vivid today than those in Renaissance oils. On the other hand, the paint lacks the flexibility of oils and so has a tendency to crack if the wooden panel swells or shrinks owing to changes in temperature or humidity.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1905-1908). Random House. Kindle Edition.

‘Fine blue is derived from a stone and comes from across the seas and so is called ultramarine.’

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 1931-1932). Random House. Kindle Edition.

Cennino recommends a sprinkling of gold mixed with green paint for ‘making a tree to look like one of the trees of Paradise’. Botticelli laces his goddess’s hair with gold in The Birth of Venus (c. 1485), and scatters it among the leaves of the trees behind her.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 2063-2065). Random House. Kindle Edition.

the Virgin’s robe is given highlights using a fine peppering of gold dots, creating a fine, silky and quite numinous quality in the cloth.

Ball, Philip (2012-08-31). Bright Earth: The Invention of Colour (Kindle Locations 2075-2076). Random House. Kindle Edition.