The Science of the Palette

Philip Ball, the author of Bright Earth: Art and the Invention of Color, talks about the intersection of art, science, and creativity


Bright Earth: Art and the Invention of Color
by Philip Ball
Farrar, Straus & Giroux
382 pages, $30.00

On a wall in London's National Gallery hangs one of van Gogh's famous Sunflowers paintings—an understated arrangement of thickly layered ochres, muted oranges, and russet browns depicting a flower-filled vase against a brownish-yellow background. The thoughtful viewer might seek to analyze why van Gogh used such uncharacteristically subdued and harmonious colors. (Perhaps, one might guess, the painting was created during a period of respite from his notorious torment?) And the thick daubs of crudely applied paint might seem to suggest an impulsive approach on his part—a giving over to spontaneity in place of careful planning.

In fact, as pigment analysis indicates, van Gogh's painting today little resembles the way it looked more than a hundred years ago when it was first completed. The "chrome yellow" pigment that figures heavily in the work was, at the time, a vibrant, brilliant color—in keeping with van Gogh's more typically lurid color schemes. But over time it faded to the lusterless brown-yellow that it is today, transforming the overall feeling of the work. As for the thickness of the paint, that can be explained at least in part as symptomatic not of impulsiveness but of the artist's foresightful awareness that some of the pigments he was using might not stand the test of time because they had only recently been developed by the fledgling chemical industry. One might as well "lay them on ... crudely," he wrote in a letter to his brother, because "time will tone them down only too much."

As the science writer Philip Ball makes clear in his new book Bright Earth: Art and the Invention of Color, without a knowledge of the history, composition, and cultural conventions of painterly color, much can elude even the most observant and otherwise well-informed art critic. Inseparable from the story of art, he argues, is the story of the development of artistic color. Ball traces this development from the surprisingly sophisticated scientific capabilities of the ancient Egyptians—who created such pigments as Egyptian blue (from limestone, copper, and sand) and pale yellow (from lead oxide and chemically transformed minerals)—to the secret alchemical color recipes of the Middle Ages, the advent of oil painting in the Renaissance, the rise of the chemical industry, the birth of photography, and the dawn of the digital age.

The range of available artistic color, he emphasizes, plays a far greater role in the choices an artist makes than is often recognized:

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?

In some cases, the sheer difficulty of creating a particular dye or pigment has given a color an aura of mystique or sacredness. The Virgin Mary, for example, was often depicted wearing a deep blue robe in medieval paintings, not because she was believed to have actually worn such a garment, but because the extremely complex and time-consuming process of deriving ultramarine blue from the rare stone lapis lazuli rendered the color off limits for all but the most precious of subjects. Indeed, the use of ultramarine or gold, Ball explains, "does not simply imply a wish to show piety by lavishing expense but reveals the hope that the supernatural potency of the work will thereby be enhanced."

As a scientist with a background in chemistry and physics, Ball has an in-depth comprehension of the dynamics of the substances he describes and of the scientific processes that affect how we perceive them. His explanations are thorough enough that one comes away from the book not only with a broad sense of how science and art intersect, but also with specific knowledge about light wavelengths, color chemistry, film and printing technology, and the mathematical rules governing digital color.

By educating ourselves about such matters, Ball suggests, we can transform our understanding of art itself. He describes his own awakening after having immersed himself in the study of color:

Where before there were two-dimensional images in gilded frames, there was now a living world. Each picture seemed as though it had just left the artist's workshop or studio, the paint's transition from palette to panel or canvas almost visible in the brush marks. Of course, time, too, has left its mark: paintings often need more decoding than the artist intended, as greens darken to black and reds fade to pink. In the end, learning the language of color is really about learning to see.

Philip Ball, who majored in chemistry at Oxford and has a Ph.D. In physics from the University of Bristol, is a writer and editor for Nature. His previous book, published in 2000, is Life's Matrix: A Biography of Water.

He spoke with me by telephone from London.

—Sage Stossel


Jonathan Coe
Philip Ball   

What inspired you to explore the subject of color?

It came from small beginnings. I attended a couple of lectures given by chemists who were exploring various aspects of color. In particular, there was a chap who studied pigments in manuscripts for the British Museum using a spectroscopic technique to verify that the pigments matched those that were available at the time.

To make sure they weren't forgeries?

That's right. And it set me thinking about the question of where painters got their pigments from. It's an aspect of art that I had never really considered before. One or two comments that he made about the broader context made me realize that in the past artists were very much limited by what resources were available—which minerals were in their local environment, or which trade routes were nearby. And the more I began to look into it, the more I realized that these were limitations that applied not only to the earliest of times, but also to relatively recent times.

In the preface, you mention that you spent two years immersing yourself in the subject of color and art. What did the research process involve?

I have training as a physicist and chemist, so I already had some familiarity with the components that were involved—the pigments and the dyes. But I had only a layperson's knowledge of art history and how those dyes and pigments fit into the art-historical context. It became clear to me very quickly that it would be a mistake to think that artists were making their choices solely on the basis of what the technologies could provide them with. Certainly the availability of various materials limited the choices they could make, but it wasn't always the determining factor. Sometimes artists limited their palettes by choice rather than because of technical constraints. For example, in ancient Greece many artists used a four-color palette even though there were more colors than that available to them at the time. It was an aesthetic choice rather than one forced upon them by technology. So the general social context within which art was created was something that I found I had to try to get to grips with.

After having done a year or so of research, I went to the National Gallery in London and had a look at the pictures—and it seemed like they were transformed. Everything suddenly made much more sense. This window on art had given me a vocabulary with which I could begin to understand what the artists were doing and the way they were working.

Did the knowledge you gained about color and artistic technique end up affecting your taste in art or your esteem for certain artists?

Yes, it really did. That was another surprising thing. In particular, I was surprised by what happened to my perception of Renaissance art. A lot of Renaissance artists tended to explore classical or religious themes that seem quite remote from our experience now. I had found Renaissance art quite inaccessible in the past, but by having some knowledge of why it was made and the conditions under which it was made, and how artists at the time were working, I was better able to understand not only what was physically on the canvas, but also what was motivating and inspiring the artists. It also enabled me to distinguish between the individual styles of different artists. Previously, I would have seen something like a Titian as very similar to a Bellini or a Michelangelo to me. But now they look worlds apart.

Do you think that a greater understanding of the development of painterly color on the part of art historians and critics could reshape conventional wisdom about the history of art and the pantheon of great artists?

I wouldn't want to give the impression that this is something that's being completely ignored by art historians. But I think it's currently seen as a rather specialized field of research. It seems to be largely restricted to conservators at museums who, of necessity, have to know something about the material aspects of the works as well as the art-historical context. It was largely people of that sort whom I discussed the topic with. There does seem to be something of a disjunction between that world and the world of traditional art history and criticism, which is much more concerned with the aesthetic qualities of art. What materials the painters were using and where they were getting them from (and how much they were paying for them)—all of this inevitably affects the choices artists make about which colors to apply and what techniques to use and what they're trying to achieve. By not understanding these craft aspects of making art, we run the risk of imagining that art is just about having the idea rather than about actually having to go about creating it. I do think this is a perspective that has been underplayed in conventional art history and art criticism, and that it could be brought closer to the fore.

Why do you think it is that most art criticism tends to skimp on discussion of the artist's materials and craft and focuses instead on the final product? Is it that most art critics have little experience as artists themselves?

I think that's partly the case. There are plenty of artists who have quite an intimate relationship with the materials they use. They go out and carefully look for particular pigments or particular kinds of paint. They often establish relationships with particular producers of paint. Some artists mix their own paints from raw pigments because that's the only way they can get the consistency or quality they want. Yves Klein, for example, was an artist who wanted to express quite ethereal and abstract ideas in his paintings. But in order to do that the way he wanted, it was very clear to him that he needed to put a lot of work into developing a particular kind of paint that just wasn't available. So he established a collaboration with a Parisian paint manufacturer in order to realize what he had in his mind. I think that all of this tends to be overlooked when the works are discussed by critics. The disjunction between the practitioners of art and the people who comment on it seems to be rife with the potential for missing something important about what artists are trying to do.

Were you surprised by some of the outlandish substances and processes people experimented with over the years in the search for new ways to manufacture colors?

What particularly struck me was how much serendipity was involved. Many new pigments came from accidents of some kind or another. For example, one of the processes that is now used to make zinc oxide (which was used as a white pigment, "Zinc White"), came about when a factory worker was trying to put out a fire one night. He grabbed hold of some lumps of rawzinc ore and put them over the fire and then found later on that they had been transformed into this white substance. There seemed to be lots of accidents like that which have given rise to new processes.

There are certainly some dramatic stories about the lengths people have gone to. One of the best known is the case of Indian Yellow, which became available in the seventeenth and eighteenth centuries. It was a lovely golden yellow that worked best as a watercolor. It was imported from the British and Dutch colonies in India. But people in Western Europe didn't know what it came from. It was only in the nineteenth century that it was traced back to its source. It turned out that it was being produced by dairymen who were feeding their cows exclusively mango leaves and then collecting their urine and heating it to produce a kind of yellow precipitate which they compacted into little balls. These yellow balls would come to the Western artists smelling strangely, and all sorts of legends grew up about where they came from. There was some speculation that they were made from camel or snake urine. This was, I suppose, one of the most lurid examples.

A significant emphasis of your book is on the search by various chemists to learn how "nature's chemistry could be equaled in the laboratory," and you describe the tinkering they undertook and the excitement of various discoveries they made. Would you say that your book makes a case not only for the importance of the role of science in art, but also for science as perhaps a kind of artistic enterprise in and of itself?

I see what you mean. When people talk about science and the practice of science, almost invariably they'll start talking about theories and ideas. Clearly that's a huge part of science. But there's also another part that has much more to do with the business of fabrication—of making things. I think it would be fair to say that most science is actually done with some practical end in mind—often with the intention of making some device or substance or drug or whatever. The kind of science that was involved in the making of color was very much of that ilk. It was driven by the social demand for new colors. The experimentation involved in trying to develop those colors often led to understanding of new aspects of science.

Your description of the rush to create new colors in the nineteenth century which led to scientists creating all sorts of other unanticipated things as byproducts reminded me of the way biotech companies today are coming up with various drugs that keep turning out to have all sorts of unanticipated uses. Do you see a similarity between those two eras in science?

I think there is. There's even something of a methodological similarity. Some of the drug companies are realizing that our theoretical understanding isn't sufficient yet to really design drug molecules from scratch, so they're employing trial-and-error methods: they make libraries of potential drug molecules and then screen them to see which ones will be useful. It's called combinatorial chemistry. That was very much what was being used in the early days of pigment manufacture. People were looking for new colored substances, but they didn't really know how color arose—what elements and what mixtures were involved. So in many cases they would just mix things and see what came out.

In your view has something valuable been lost by the dissociation of the artist from the process of color-making? Did art-supply stores, for example, which emerged in the nineteenth century, have the effect of rendering artists somewhat complacent when it came to envisioning what materials they might use and how they might use them?

I think something has been lost. You can certainly see throughout the nineteenth and twentieth centuries how some artists' works have suffered from the artists' unfamiliarity with the materials that they were using. There are some works by modern painters—for example, by Mark Rothko—that are in much worse condition now than works by Van Eyck from the Renaissance. Many of the modern painters had a less intimate understanding of their materials and less understanding of how to get the most from them and how to make sure they would last. But in a way I think these questions about familiarity with painting materials may be becoming moot because painting is such an unfashionable art now. Many contemporary artists want to explore completely new media—video, installation, sound and light, and so forth. Some artists, like James Turrell, are using light instead of pigment. He's making works of art that change color as the sky changes color. And there are artists using the colors that are available digitally on computer screens. Computer art still hasn't taken off yet, though. I don't think anyone's really found a way to use that medium to its proper potential so far. But it's quite likely that someone will, and that new things will happen to color as a result.

Artists have always wanted to push at the edge of what's possible. And if you want to do that, almost by necessity you're going to be using materials and techniques that haven't been tried and tested yet: you're going to be taking risks. That's something art always needs to do.

What do you hope that artists who read your book will take away from it?

I've had a few pieces of correspondence from artists who feel they've gotten something out of it, and that's been very inspiring. The impression I get is that they feel they lack an understanding of their materials and have found it difficult to find information about them. So if my book provides a pointer to sources of information about those materials, I think that's a useful thing. But the book certainly isn't intended as a technical manual. It doesn't have that amount of information. What I'd rather try to do is re-establish a link with the past so that artists today, who are faced with the dilemmas of how to select and work with particular colors and materials, can see how those same dilemmas have been faced by other artists of other times.

If artists were to learn more about the history of color, might they be able to choose particular colors to represent particular concepts? If artists were aware, for example, that a given color had in the past been derived from some particular type of animal or element, then couldn't their decision to use that color resonate with where it comes from and how it has been used in the past—and thereby gain an added layer of meaning?

That's something I would be excited to see. I don't know of any examples where that's been done, though. I think partly the difficulty is that paints don't come from such resonant natural sources anymore. Most pigments are synthetic petrochemical products. So they don't have these emotive links. But I've been intrigued by glimpses of ways in which some modern artists have tried to suggest a sort of material link with the past. For example, Yves Klein created a beautiful work which basically consisted of pigments in a plastic case. He chose to use ultramarine, gold, and a very vibrant red pigment. This seems to me to be a very clear evocation of the three classic primary pigments of the Middle Ages and the Renaissance—ultramarine, gold, and vermillion. He created the work as a devotional offering—a religious offering. It very much made a connection with the way those pigments themselves were venerated in the Middle Ages.

You write about the importance of artists' knowing which materials will age in what ways, so that their works will hold up over time. Are there any artists who study the way the materials will fade or buckle or crack in order to incorporate that degenerative process into their works of art in an intentional way?

I have seen examples of that—not with paint, but with other materials. Some artists are interested in processes of decay or corruption of materials. For example, there was the case of Andy Warhol using a metal-based paint that he and his assistant urinated onto which produced amazing patterns of corrosion. They're actually very striking and quite beautiful. I also know of an artwork where sand was packed into a frame and then allowed to gradually fall out, creating a landslide-type process. And then there's a British artist named Glen Onwin, who has created works of supersaturated salt solution that constantly precipitate islands of salt which appear and then dissolve again.

It struck me that someone who knew their paint materials well enough could do a "Portrait-of-Dorian-Gray" type work—with hair painted a color that would gradually fade to gray, and paint that would wrinkle around the eyes and so on.

Yes, by looking at the different rates of pigments' fading in sunlight. An artist may have done that—I don't know. But it certainly would be an interesting thing to do.

You suggest that it's best to study original artworks rather than reproductions when trying to understand an artist's use of color, because, as you point out, "no two reproductions will look the same." Yet you've included a number of reproductions in this book to illustrate various points. Did you have to take special steps to oversee the color printing process in order to ensure that the images were as accurate as possible? How satisfied were you with the result?

I went into the publishers at Penguin several times to check the printed versions against the transparencies we'd been sent to get the colors matched as closely as possible. And in doing that there was one particular image that was quite frightening in what it revealed to me about the extent to which we rely on reproductions for our perception of a work. It was the picture of the Madonna by Raphael. It was a work that I had seen originally in Ernst Gombrich's The Story of Art. There it seemed to be a beautifully harmonized picture of the Madonna in a red gown with a green robe over the top of it. So I wrote about it in that sense. Then I was lucky enough last summer to go to see the original in Florence in the Palazzo Pitti. And it was completely different. The colors were nothing like what I had seen in the book. The green robe wasn't green at all. It was a kind of aquamarine blue. Then when I got the transparency from the Palazzo Pitti I was assuming that wouldn't be a problem—that it would be an accurate reflection of the actual colors. But in fact it wasn't. Both the transparency and a postcard I had bought to use as a reference showed the robe as a kind of royal blue, which I knew from my memory was not the same color. I don't know quite what Raphael used in that color, but whatever it was, it's extremely difficult to reproduce with modern photographic technology.

Your training is in chemistry and physics, but you've ended up as a writer. Did you always have an interest in writing, or is this an unexpected twist in your career path?

I sort of fell into it, I have to admit. Writing wasn't an ambition I harbored when I went into science. But I found that I enjoyed writing about the research I was doing as much as actually doing it. And I could see that my path, if I stayed in research science, would continue to get narrower and narrower. So I was lucky enough to be able to step out when I finished my doctorate and go to Nature, the science journal, as an editor. The writing really came out of that. I was doing editorial work there, but I found that I wanted to do more and more writing.

What appeals to me now is being able to step outside of scientific disciplines and write about something that's related, but that's not a topic in chemistry or in physics. It's those topics that span scientific disciplines and that have some kind of social relevance that really draw me.