Making colours & “noncolours”

Last weekend I went to the National Gallery to see the Making Colour exhibition. It’s one of those exhibitions I could easily have missed, had it not been recommended to me by a friend, since its advertising is not especially enticing. But I’m very glad I went for it’s a really good show: inspiring, informative and joyful. Everyone who marvels at the colour exuberance of Matisse’s cut-outs at Tate’s best-selling exhibition (which I’ve reviewed in one of my recent posts), should enjoy the National Gallery’s journey through the history of pigments, dyes and their use in paintings.

Colour is something we take for granted, and its widespread use in contemporary art and media results from the easiness of colour making and its availability. It is no longer the case of risky and laborious mining and transportation of stones used for making pigments, like the lapis lazuli. This precious and incredibly expensive Afghani stone, excavated from the mountain valley of Kokcha (hence the name ultramarine, meaning “beyond the sea”), was used by the Renaissance artists to paint the blue robes of the Virgin Mary. It was only in 1826 when a synthetic called “French Ultramarine” was invented. Before that, artists who couldn’t afford ultramarine had to choose between cheap and unreliable smalt (made from ground blue potassium glass containing cobalt) and greenish azurite (composed of mineral basic carbonate of copper). The third source of blue, which was also the first synthetic pigment called “Egyptian blue” and used extensively from the early dynasties in Egypt until the end of the Roman period, was no longer an option since its recipe was forgotten in the Middle Ages.

The Blue room, where minerals and pigments are displayed next to paintings, is the second one at the National Gallery exhibition. The show begins with an introductory room where Moses Harris’s The Natural System of Colours chart from the late 18^th century is juxtaposed with Michel Eugène Chevreul’s idea of complementary colours (i.e. blue and orange) which enhance each other when placed side by side. The subsequent rooms are each devoted to one colour: green, yellow, red, purple, gold and silver, and show us how these colours have been created, used and how they have aged. Thanks to the cutting-edge laboratory equipment, it is now relatively easy to establish exactly what went onto canvas several centuries ago in terms of the colour composition, hue and saturation, before the ageing of pigments, exposure to light and oxygen completely changed the colours, giving for example the 15^th century landscape painting the “burnt effect.”

Modern painters not only have the luxury of choosing from hundreds of ready-made secondary colours which come in a variety of tube sizes, but they also don’t run the risk of poisoning themselves in the process of mixing pigments with oil. Realgar, which for centuries was the only available pure orange pigment used by artists such as Titian and Dutch masters, is a highly toxic arsenic. It was used to poison rats in medieval Spain and in 16^th century England. Verdigris, another toxic pigment and the most vibrant green available until the 19^th century, was made by scraping the oxidation off copper and bronze. Copper resinate, introduced in European 15^th century easel panting, was formed by dissolving copper salts in Venice turpentine. Artists would often combine glazing verdigris over lead white with a layer of copper resinate to form a deep saturation of green. It wasn’t until late 18^th century when a new generation of greens was formed: cobalt green, emerald green, and viridian. As for reds, Vermilion, originally made from the powdered mineral cinnabar, was used scarcely, as mining cinnabar was difficult, expensive and dangerous due to its toxicity. When in the 9^th century people discovered a safer process of making the pigment, it became the principle red pigment until the manufacture of its synthetic equivalent, cadmium red, in 1907. This was a welcome discovery, for despite the new and improved methods of obtaining vermilion, it remained toxic.

The strongest point of the exhibition is its technical approach to the subject: showing sources of red dyes (brazilwood, madder, stick lac, kermes, cochineal), x-raying old paintings, juxtaposing hidden edges of the canvas containing the original colour with the decoloured rest; or describing the process of applying gold leaf in Botticelli’s Saint Francis of Assisi with Angels (1475-80). There are also quite a few gems: David Contemplating the Head of Goliath (approx. 1612), a painting by Orazio Gentileschi executed directly on a panel of lapis lazuli, with the sky area uncovered with paint; The Virgin and Child Enthroned with Angels and Saints (1475), quite a stunning painting by Michael Pacher, and Turner’s paintbox, found in his studio after his death in 1851.

The curators also wanted to draw our attention to the subjectivity of colour perception – something that is explored in the last room, where the audience can participate in a series of visual experiments. One of them is particularly impressive: after staring for a while at a black dot placed in the middle of a bright infrared-like image of a castle, we will see a completely natural-looking colour photograph of it, despite the fact that the image we’re shown is black and white. It is our mind that makes up the colours.

There are indeed a few different angles to the exhibition, which makes it particularly interesting. However, this is by no means an exhaustive exploration of the topic. With only a few examples from the 20^th century, the show fails to demonstrate the tremendous difference in the use of colour between old and modern paintings. Some colour rooms are more informative than others (why is there so little information about Prussian blue?), but what struck me most is that the exhibition doesn’t include two other colours that are fundamental to painting – white and black.

I am aware that these two colours can easily inspire heated debates, with speculations around their existence. According to Michel Pastoureau, the author of Black: The History of a Color, published by Princeton University Press, for a few centuries after Isaac Newton’s discovery of the colour spectrum, “black and white were considered and experienced as ‘noncolors.’” This notion still affects the way students are taught at art schools. Painters are expected to create black by mixing other colours, since they have a greater ability to suspend colour constancy (the process in which the perceived colour of objects remains relatively constant under varying illumination conditions). In other words, they are not only able of capturing the way a different light alters the colour of an object, but of seeing crimson and ultramarine in a tarmac, and therefore should refrain from using ready-made black. I must say that I never really understood that dismissal. After a few years of following my tutors’ directive to avoid black, I eventually went back to it.

When I didn’t know what colour to put down, I put down black. Black is a force: I used black as a ballast to simplify the construction. – Henri Matisse

After all, black was one of the first colours used by artists in Neolithic cave paintings. The first type of black was Carbon black, made by heating wood, or other plant material, with a very restricted air supply. It was quite dull but the easiness of its made it incredibly popular among artists of all periods. The name carbon black is a generic name for different blacks made from the partial burning or carbonizing of natural gas, oil, wood, vegetables and other organic matter. Besides carbon black, there is vine black, produced by charring desiccated grape vines and stems, and lamp black, made by collecting soot. Bone black, with a slight blue hint, and fairly smooth texture, is made from charring of bones or waste ivory. It is the deepest available black. In the Portrait of Phillips Lucasz, Rembrandt used bone black to paint the black clothing of the man in order to distinguish him from the already dark night surroundings. As Pastoureau says, the painter “often practices a kind of colour asceticism, relying on dark tones, restrained and limited in number . . . to give precedence to the powerful effects of light.” Mars Black , the most recent in origin (early 20th century), is the only major black pigment that is considered non-toxic and the only one that is a good drier (the other blacks are among the most slow-drying pigments.)

(…) White, although often considered as no color (a theory largely due to the Impressionists, who saw no white in nature), is a symbol of a world from which all color as a definite attribute has disappeared. This world is too far above us for its harmony to touch our souls. A great silence, like an impenetrable wall, shrouds its life from our understanding. White, therefore, has its harmony of silence, which works upon us negatively, like many pauses in music that break temporarily the melody. It is not a dead silence, but one pregnant with possibilities. White has the appeal of the nothingness that is before birth, of the world in the ice age. – Wassil Kandinsky

Along with charcoal and red and yellow, white was one of the first colours cave artists painted with. They used calcite or chalk – a kind of limestone, made of the mineral calcite, or calcium carbonate. The Renaissance brought a new pigment similar to chalk, called “Bianco di San Giovanni,” made of calcium carbonate with calcium hydroxide. It was essentially lime powder, soaked in water, formed into cakes and dried in the sun. Lead white was being produced from the 4^th century BC until the late 20^th century when it was finally banned due to its toxicity. “Pieces of lead were put into clay pots which had a separate compartment filled with vinegar. The pots in turn were piled on shelves close to cow dung. The combined fumes of the vinegar and the cow dung caused the lead to corrode into lead carbonate,” we can read on the Wikipedia. Today, the two most widely used whites are zinc white and Titanium white (made with titanium dioxide); the latter was discovered in 1921 and turned out to be an excellent replacement for the toxic lead, with twice its opacity.

Despite the non-colour stigma, white and black have been used for artists across centuries. Black, which also had various negative cultural associations, can be found not only in Rembrandt’s portraits and Matisse’s works, but in the work of many great painters: Diego Velázquez, Francisco Goya, Jean Miro, Pierre Soulages, Kasimir Malevich, Robert Motherwell, Franz Kline, Ad Reinhardt, Frank Stella, Louise Nevelson, Barnett Newman to name a few.

The artistic mission of Pierre Soulages, often referred to as the “Master of Black”, has been the search for a particular onyx gleam which he calls “outrenoir,” or beyond black. In his teenage years, the artist was fascinated by prehistoric art such as the 3,000-year-old monoliths near his home in the Aveyron region, and the reproductions of the cave paintings at Lascaux, Altamira or Chauvet from 30,000 years ago. This idea that prehistoric people painted in the dark and with the dark, inspired his lifelong fascination with black.

The majority of works by the minimalist/abstract artist Robert Ryman feature white or off-white paint on square canvas or metal surfaces, referred to as “white-on-white” paintings. White was also the love of Piet Mondrian, who used it to cover large sections in his Compositions and later made white the focus on his paintings. Another striking example of the use of white are the five works in Robert Rauschenberg’s White Paintings (1951) which have been painted completely white. The artist’s goal was to “create a painting that looked untouched by human hands, as though it had simply arrived in the world fully formed and absolutely pure. (…) Rauschenberg once referred to the works as clocks, saying that if one were sensitive enough to the subtle changes on their surfaces one could tell what time it was and what the weather was like outside,” we can read on the San Francisco Museum of Modern Art website.

After seeing the National Gallery exhibition, which successfully demonstrates the amount of effort and dedication that went into obtaining pigments and creating colours in the history of art, I can’t help but wonder about the works of artists such as Pierre Soulages or Robert Rauschenberg. I find it interesting that the 20^th century painters who suddenly had access to so many different colours, would often limit their palette to black or white. Perhaps the clichéd saying that the more available something is, the less desirable it becomes, is accurate. Artists need challenges and with the abundance of materials and techniques they can choose from, they might be more inclined to create work with some obscure tools than with the top quality painting and glazing mediums from art shops. The exhibition makes us more aware of the limitations painters had to embrace in the past and more appreciative of the works created at a time when certain pigments were only available to the rich, mixing pigment was a potentially deadly task and the behaviour of the paint was entirely unpredictable.

When writing this blog post, I was referring to the Pigments Through the Ages guide, which I highly recommend for further reading.