The element chromium gains its name from the rich colours seen in many of its salts and compounds. One of them, chromium oxide, was discovered in about 1798 by Louis-Nicolas Vauquelin, who immediately recognised its future use as a pigment, because of its “fine emerald colour”. But painters were still enamoured with more toxic greens, and straight chromium oxide doesn’t look particularly brilliant, being a rather dull yellow-green. Its introduction into paintings probably didn’t start until around 1840, when landscape painting outdoors was becoming all the rage.

Some of the earliest paintings known to use chromium oxide are those of Moritz von Schwind, of which the first example that I can show is his Mermaids Watering a Stag from about 1846. He seems to have used the pigment quite extensively here in foliage, although probably in combination with other pigments.

Von Schwind’s King Krokus and the Wood Nymph from about 1855 is a clearer image, where he probably used chromium oxide in combination for most of his greens.

As these works were being painted, an improved version of chromium oxide was being developed: hydrated chromium oxide, which became known as viridian during the 1860s. This first became available at a reasonable price after Guignet started to make it in quantity in 1859, so has also been known as Guignet’s green. It’s sometimes termed émeraude or emerald, which only serves to confuse viridian with copper acetoarsenate, more widely known as emerald green.

Viridian came into use during the 1860s, and has proved far more popular than chromium oxide. Both pigments are reliably lightfast, opaque, and have good covering power, but viridian is the more intense, and doesn’t appear dull like plain chromium oxide.

Anselm Feuerbach’s painting of Paolo and Francesca from 1864 is one of the earlier works found to contain viridian among its many rich greens.

The best example showing off the colour of viridian is perhaps Édouard Manet’s The Balcony (1868-69), where he appears to have used the pigment throughout the blinds and railings, most probably mixed with lead white, and unmixed for the woman’s parasol.

Arnold Böcklin’s Triton and Nereid from 1874 is unusual in several respects. It’s reported as being painted in tempera rather than oils, but its deep lustrous greens were developed using a base of predominantly viridian, over which Böcklin applied a copper resinate glaze.

Pierre-Auguste Renoir’s La Yole (The Skiff) of 1875 uses viridian as the main colour for the reeds in the left foreground.

Analysis of Claude Monet’s series of paintings of the Gare Saint-Lazare in 1877 has revealed extensive use of viridian in mixtures, including the green shadows in the roof. In Arrival of the Normandy Train, Gare Saint-Lazare (1877), the pigment is apparent (and confirmed) throughout the green foreground of the platform, an optical effect resulting from light passing through the glass roof of the station.

Renoir used viridian together with malachite green and other pigments for the greens in his Chrysanthemums (1881-82).

If you care to spend some time examining the myriads of tiny dots in Georges Seurat’s monumental Divisionist painting of A Sunday Afternoon on the Island of La Grande Jatte (1884-86), I’m assured that you’ll find many of those forming its vegetation contain viridian.

Viridian remained popular among the post-Impressionists, from whom I have two well-known paintings as examples.

Vincent van Gogh included viridian in the pigments used in the range of greens in his A Wheatfield, with Cypresses (1889), which is more unusual for his use of ultramarine blue mixed to form green.

Paul Cézanne is known to have had a strong preference for viridian as one of the key colours in his palette. However, in his Hillside in Provence (1890-92), it is emerald green that is the more prominent, and the major part of the painting’s more brilliant greens, even into its pale turquoise sky. Some green passages, such as the patch of yellow-green grass at the edge of the path in the foreground, at the right edge of the canvas, have been built with a base of lead white and viridian, over which he has applied a yellow lake glaze.

Chromium oxide and viridian remain widely available today; although the former is not popular or widely used, viridian remains a mainstay green widely recommended for its colour and other properties. Being virtually insoluble, chromium oxide and viridian pose minimal risks of toxicity to the artist. However, there is growing concern over their environmental effects, and great care is needed when handling waste paint containing either pigment.

Reference

Richard Newman (1997) Artists’ Pigments, vol 3, ed Elisabeth West FitzHugh, Archetype. ISBN 978 1 904982 76 0.

Rumours still abound as to the cause of Napoleon’s death over two centuries ago. One theory, not currently in favour, is that he was poisoned by arsenic in the wallpaper. At the time, that would have been unusual, but by the 1860s such deaths were significant enough to be reported in newspapers. Their ultimate cause was also one of the factors behind the success of Impressionist landscape painting: emerald green.

Getting a good range of green pigments was vital for landscape painting, and more generally for coloured commercial products such as wallpaper and clothing. The first of the ‘poison greens’ to be discovered was that named after Carl Wilhelm Scheele, the Swedish chemist who originally made it in 1775: copper arsenite, a highly toxic salt of arsenic. Soon after its introduction from about 1780, it became clear that it tended to darken with age, and the search began for a replacement.

Little attention has been paid to the use of Scheele’s green, and it isn’t clear how widely it was used, or even when it was first used in painting.

JMW Turner’s early oil sketch of Guildford from the Banks of the Wey, painted in about 1805, has been found to contain Scheele’s green. Given its range of greens, that could be quite extensive.

Wilhelm Sattler, a paint manufacturer in Schweinfurt, Germany, worked with Friedrich Russ to discover an even better arsenic compound for use as a colourant, and from 1814 Sattler’s company manufactured Schweinfurt or emerald green, the equally toxic copper acetoarsenite. Its alluringly brilliant green colour appears very stable, with only slight darkening resulting from reaction with hydrogen sulphide, a common atmospheric pollutant.

By about 1830-32, when Turner painted Going to School as an illustration for Rogers’s Poems, he had switched to using emerald green, obvious from its characteristic colour standing out from the small bag on the boy’s back.

Turner used emerald green again in this watercolour painting of Rouen, Looking Downstream from about 1832, here in combination with other pigments, so less brashly.

Concerns over the established toxicity of these two greens were raised by 1839, when warnings were first issued in Bavaria. Despite those, the use of emerald green became more widespread, and it was even ‘fixed’ to ball gowns using albumen or dextrin, which allowed its poisonous dust to brush free from the garment when dancing. It also became particularly popular, and insidiously toxic, in coloured wallpapers. When applied on damp walls, as were common at the time, fungal products could produce trimethyl arsine gas, which is thought to have been responsible for many of the symptoms and deaths that were reported.

Édouard Manet’s Music in the Tuileries (1862) is an unusual example of a painting containing both Scheele’s and emerald greens. Manet used them in combination in two different glazes applied to the areas of foliage. In one transparent glaze, they are mixed with yellow lake, small amounts of ivory black, and yellow ochre; the other more opaque glaze consists of the two greens, with yellow ochre and white.

The last recorded use of Scheele’s green was by Edwin Landseer in 1866.

The Impressionists relied heavily on emerald green for its brilliance and intensity of colour. Frédéric Bazille’s Self-Portrait with Palette (1865) shows some emerald green paint on his palette, squeezed out and ready to paint vegetation such as sunlit grass.

Claude Monet used emerald green among other green pigments and mixtures in his famous Bathers at la Grenouillère, painted in 1869. It has also been found widely in the landscapes of Cézanne, Gauguin, Pissarro and Vincent van Gogh.

By the late nineteenth century, concern over the consequences of using emerald green in household products had risen to the point where the pigment was banned in a succession of countries.

Paul Gauguin’s Arlésiennes (Mistral) (Old Women at Arles) (1888) uses emerald green for the band of bright green grass sweeping up across the painting from the right. It is also mixed for the skin and hair of some of the figures, and in the foliage more generally.

Odilon Redon’s pastel painting of Sîta from about 1893 uses emerald green, chrome yellow and chalk in the prominent yellow-green halo surrounding the woman’s head. Working with soft pastels containing this pigment was particularly hazardous, because of the likelihood of inhaling their dust. At least today we have effective respiratory protection available.

During the twentieth century, genuine emerald green was withdrawn from use as a pigment, although it wasn’t completely discontinued until the 1960s. Since then, paints sold as being emerald green have contained alternatives that are far less toxic.

Emerald green has been found in mixtures used by Paul Cézanne in the patches of vegetation in his huge The Large Bathers (1906). Alongside lead white, vermilion and ultramarine blue, this pigment appears to have been among his most frequently used.

Childe Hassam’s watercolour of White Mountains from Poland Springs from 1917 is one of the last major paintings that appears to have relied on emerald green. Its use in the meadow in the foreground is perhaps the pigment’s last brash farewell.

Reference

Inge Fiedler and Michael Bayard (1997) Artists’ Pigments, vol 3, ed Elisabeth West Fitzhugh, Archetype. ISBN 978 1 904982 76 0.

As we all should really be on holiday, I’m taking a long weekend to look at the stories of three green pigments, starting today with the oldest and most elusive of them, the mineral malachite.

Because green is a secondary colour, it might seem better mixed from blue and yellow, as it has been in various recipes such as Prussian green. But the painter always prefers using single pigments for the purity of their chroma, and the fact that the more pigments that get mixed, the closer the colour comes to muddy grey.

Given the shortage of lightfast bright greens, it’s surprising how little-used malachite green is in European painting, despite its rich colour. For a while it rejoiced quietly under traditional names including chrysocolla, green verditer, and even green bice, but it only ever became popular in Japan and China.

As a natural mineral, malachite is not uncommon, and a reliable source of pure pigment, which is chemically basic carbonate of copper. Malachite green was known to the ancient Egyptians, who appear to have used it as eye-paint. Found abundantly in Japanese and Chinese paintings from the seventh century onwards, it wasn’t used much in Europe until the Renaissance. After that, it almost died out in Europe until the nineteenth century, when it enjoyed a brief revival.

Two versions of the painting by Watanabe Kazan 渡辺崋山 of Sato Issai 佐藤一斎（五十歳）像 show malachite green at its finest.

This version from 1824, now in the Freer in Washington, is known to use malachite green with a slightly blue shade and deep in colour.

This smaller and earlier version from 1821, now in Tokyo, is a lighter, more yellow shade. I’m not aware of its pigment having been analysed, but I’d be surprised if it was straight malachite green.

The biggest problem with its adoption in Europe was the popularity there of oil paint. The pigment worked well where it could be ground quite coarsely and used in water-based media like fresco and egg tempera, but the finer you grind it, the paler it becomes. Oil painters like smooth buttery paints with fine pigment particles, which sadly didn’t work for malachite green.

The rich, almost emerald green robes of Spinello Aretino’s Virgin Enthroned with Angels from about 1380 contain malachite green, here in tempera medium.

Among its earliest appearances in oil paint is this spectacular centre panel of the van Eyck brothers’ Ghent Altarpiece, famous in its own right as the Adoration of the Lamb (c 1425-1432).

Continuing use of egg tempera in the Southern Renaissance helped it survive. Piero della Francesca’s famous The Baptism of Christ (after 1437), made in egg tempera on poplar wood, relies on the pigment for its greens. Microscopic examination of the paint layer here shows coarse mineral particles typical of natural malachite.

In Francesco del Cossa’s Saint Vincent Ferrer from about 1473-75, it has been identified in the dark green grass at the foot of the painting. This too was made using egg tempera.

However, microscopy of this paint layer shows that these pigment particles don’t seem to have been fractured as if they have been ground, but are globular, as occurs when the malachite green has been made by a process of precipitation. Such artificial malachite green didn’t appear in European paintings until after about 1430, just in time for Francesco del Cossa.

Although he painted in oils, Tintoretto was an enthusiastic user of malachite green. To obtain the range of greens seen in the rich and varied colours of vegetation in his Saint George and the Dragon from about 1555, he used this pigment with copper resinate glazes, a technique found in other paintings of the period.

Tintoretto’s vast oil painting of The Last Judgment (1560-62) in the Chiesa della Madonna dell’Orto, Venice, has been found to contain malachite green, I suspect in the band of green depicting the Flood just below the centre. The detail below makes this a bit clearer.

When painting the frescoes formerly in the Villa Aldobrandini between 1616-18, Domenichino and his assistants relied heavily on malachite green. It has been formally identified in this section, showing Apollo pursuing Daphne, where it’s the mainstay colour remaining, and is suspected in most of the others.

Although only classed as moderately permanent, these and other examples of very old frescoes show how well malachite green has retained its colour after four centuries or more. But with the rise of oil painting in European art, it fell from favour.

One of those who participated in its revival in the nineteenth century was Pierre-Auguste Renoir, whose painting of Chrysanthemums from 1881-82 shows how it could still be used in oil paint. But by then there was a much wider choice of more modern green pigments; the revival was short-lived, and malachite green has hardly been used since.

Reference

Rutherford J Gettens and Elisabeth West Fitzhugh (1993) Artists’ Pigments, vol 2, edited by Ashok Roy, Archetype. ISBN 978 1 904982 75 3.

Before I delve into painting media, it’s helpful to establish the terms I’m going to use. Although at their simplest paintings consist of a fairly flat and even surface with a layer of paint on it, in practice most have a more complex anatomy.

Earliest surviving paintings, such as these from around thirty-six millennia ago, in the Chauvet-Pont d’Arc Cave in the Ardèche, were simple applications of pigment to a stone surface. It’s a miracle that any have survived, given the lack of bonding between pigment and stone.

Fast-forward over thirty-five thousand years, and in 1570-72 Giorgio Vasari created something similar in his painting of Perseus and Andromeda consisting of pigment bound in a drying oil, applied to slate. The big difference is in his paint, which was developed over several centuries to form a strong bonded layer adhered to the surface of the rock.

Stone and walls make a robust support for a painting, but aren’t exactly portable unless they’re as small as Vasari’s sheet of slate. Alternatives were constructed from wood in panels, and could be painted on an easel rather than up a scaffold, hence these portable works of art are widely known as easel paintings, and use wood panel supports.

The next step in development was to apply a primer to the wooden panel to form a smooth surface to which the paint layer would bond better, forming the ground.

When Leonardo da Vinci abandoned his Adoration of the Magi as he left Florence in about 1482, he had applied little paint to its ground, on which he had already made extensive underdrawings and prepared tonal modelling for the paint layer he never completed.

Our easel painting now has a physical support, a purely mechanical task, and on that the ground on which the paint is applied. Those roles are distinct, even when a single surface such as a wall or sheet of paper fulfils both. Most traditional paintings by professional painters made in the last few centuries have been on supports of stretched canvas, which have been sized to protect their fibres, then had a white or tinted ground such as chalk bound to them.

Support and ground form the receiver, on which colour in the form of pigments has to be bound. Although it’s possible to get pigment to adhere to a suitably rough ground, part of the principle behind painting in pastels, the result isn’t durable, and clients and patrons are likely to be wary about paying for a painting that literally crumbles into dust in front of their eyes.

Not all paints contain pigments: some prefer soluble dyes instead. Generally dyes, often derived from plants, aren’t as durable. Pigments consist of large insoluble particles, as seen in the cross-section above, to protect them from physical damage, chemical reactions, and most importantly the adverse effects of exposure to light, which can cause their intensity to fade.

The goal of many paint systems is to trap these pigment particles in a solid layer formed by a chemical binder which is liquid when applied but hardens by the chemical process of polymerisation into a solid. In the case of oil paints, the binder is an oil that undergoes slow oxidation to form the polymer, a drying oil such as linseed obtained from the common flax plant.

The final component involved in a painting is one that should vanish during the process of applying the paint: a diluent or solvent used to thin the paint, and clean wet paint from brushes and the other tools used in the process. Diluents are often confused with binders, but they are usually opposites: an ideal diluent should evaporate quickly, leaving no residues and a robust if thin paint layer behind, for the binder to turn it into a strong, enduring and faithful record of what the artist intended.

In traditional oil painting, typical diluents are organic solvents such as turpentine and white spirit, used to spread a thin layer of drying oil binder and pigment particles. Remove most of the drying oil and use largely diluent, though, as in peinture à l’essence, used by Degas, and you can end up without any proper paint layer at all, with powdery pigment trying not to fall off.

Degas’ Danseuse dans sa loge (Dancer in her Dressing Room) (c 1879) is one of his experimental paintings using both pastel and peinture à l’essence applied to canvas.

In this respect, watercolours are strangely named. Oil paints rely on drying oils as their binder, but in watercolours the water is the diluent not the binder, which is gum arabic; many other painting methods also rely on water as diluent, but aren’t called watercolour as a result.

We finally end up with a rigid support, on which is the ground, that provides an adherent base for the paint layer, composed of pigment particles in a binder, that was originally thinned using a diluent. In most older paintings, those are then coated with layers of varnish intended to protect the surface of the paint layer.

Just like Giorgio Vasari with his oil painting on slate, there’s always someone who breaks conventions. This painting of Dandenongs from Heidelberg was made by Charles Conder on a sheet of wood from a cigar box. Conder was a member of a group of Australian artists who held a ‘9 by 5’ exhibition of paintings they had made on wooden cigar-box panels of 9 by 5 inches (23 x 13 cm) in size. Similar panels had been used extensively by Georges Seurat for his oil sketches, for which he had invented the term croquetons. They also resembled the small wood panels used by the Macchiaioli for their plein air oil sketches.

In thirty-six thousand years we have progressed from painting the walls of caves to sketching on a wooden cigar box.

Key terms

• easel painting, on a portable support rather than a wall or ceiling;
• support, a more or less rigid surface for a painting;
• ground, a priming layer applied to the support to form an adherent base for paint;
• paint layer, consisting of pigment particles in a binder, thinned during painting with a diluent;
• varnish, to protect the surface of the paint layer.

Until the advent of chemistry in the eighteenth century, early in the Age of Enlightenment, the vast majority of pigments occurred in nature, even if the minerals or plant matter from which they were derived had to be specially processed. The first truly synthetic pigment was so ancient that it had been forgotten completely by the Middle Ages: Egyptian blue was originally made before about 3000 BCE by heating together powdered rocks and sand, but that was an exception. It wasn’t until the early years of the eighteenth century that a hydrated iron hexacyanoferrate complex soon known as Prussian blue was synthesized.

No one knows who first made Prussian blue, nor exactly when it was first synthesized. It seems to have appeared initially around 1704, and its origins have been attributed variously to Diesbach in Berlin, or Mak in Leipzig. For once its name is appropriate, as it was a product of the Prussian Empire. Its potential as a colourant was recognised by 1710 when it went on sale in Berlin, and by about 1724 it was being manufactured across Europe.

Among the earliest surviving oil paintings to use Prussian Blue is that by Adriaen van der Werff and Henrik van Limborch, of Jacob Blessing the Sons of Joseph. This was started by van der Werff before he died in 1722, and the paint containing Prussian blue pigment is thought to have been applied by him to the curtain at the upper left. After van der Werff’s death, his pupil Henrik van Limborch finished the painting between 1727-28.

Another early example of the proven use of Prussian blue is Antoine Watteau’s The Italian Comedians from about 1720.

Canaletto is one of the first Masters to have used the new pigment extensively. Grand Canal from Palazzo Balbi toward the Rialto from 1720-23 has been attributed to him as one of his earliest surviving works, and its blues have been found to contain Prussian blue.

Canaletto was quick to adopt the pigment for use in almost all his paintings, including this view of the Rio dei Mendicanti from 1723-24, above, and his famous The Stonemason’s Yard (c 1725), below.

As experience was gained in using this pigment, it became controversial. Some artists were confident that its colour was stable and didn’t change or fade, but others experienced problems as bad as or even worse than those of the notoriously fugitive indigo blue, which it had generally replaced. It has gradually become understood that adverse results of lightfastness testing (and experience in paintings) have depended on the mixture of Prussian blue with other colours, particularly with white paint, and the presence of impurities in the pigment.

By the middle of the eighteenth century, Prussian blue was widely used with a range of binding media, with the notable exception of fresco and other alkaline media with which it proved incompatible.

William Hogarth’s paintings in his Marriage A-la-Mode series have been found to contain both smalt and Prussian blues. In The Tête à Tête (c 1743), smalt has been found in the ornate carpet, and I suspect that the ornamental pillars behind the woman rely on Prussian blue, at least in part. Hogarth trained as Prussian blue came to the ascendant, and wouldn’t have painted much before it had become widely available.

Jean-Baptiste Perronneau’s A Girl with a Kitten from about 1743 is a fine example of the use of Prussian blue in pastels: the girl’s blue dress and the background have both been found to contain the pigment.

Prussian blue also became popular in water-based media. William Blake’s Lucia Carrying Dante in his Sleep, from his series depicting Dante’s Divine Comedy painted in watercolour between 1824-27, is a good example. In this and several other of his paintings, Blake used the pigment on its own and mixed with gamboge yellow in what was known as Prussian green.

Prussian blue pigment has been found in the blue passages in Whistler’s The Princess from the Land of Porcelain (1863-65), from his Peacock Room, shown above and in the detail below.

The use of different blue pigments varied markedly among the French Impressionists and their successors. Paul Cézanne and Georges Seurat appear to have used Prussian blue seldom if at all, but it’s well known in the work of Edgar Degas, Claude Monet and Vincent van Gogh.

Although Monet’s Bathers at la Grenouillère (1869) contains cobalt blue in the brighter mid-blues of the water surface and details in the boats, darker blues towards the left, and in the clothing of some of the figures and their reflections, are almost certainly Prussian blue.

Vincent van Gogh’s portrait of La Mousmé from 1888 illustrates some of the difficulties of identifying pigment use. Its unusual title is derived from the Japanese word musume, meaning girl; at the time the French word was understood to mean an ‘easy’ girl.

Infra-red images demonstrate van Gogh’s use of at least two different blues, one of which has been identified as Prussian blue. The two (or more) blue pigments aren’t distributed evenly: on the girl’s jacket, the three blue stripes to the left of the row of buttons contain the most Prussian blue, while the three under her right armpit, which look darker, contain little or no Prussian blue. Van Gogh also mixed yellow with Prussian blue to form the green of the flowers she holds in her hand.

Prussian blue remained a popular pigment in oil and watercolour paints well into the twentieth century, and is still offered in commercial ranges. For many artists, though, it has been replaced by much more recent synthetic blue pigments, such as phthalocyanine (‘phthalo’) blue, introduced around 1970, and is seldom used in Prussian green.

Reference

Barbara H Berrie (1997) Artists’ Pigments, vol 3, ed Elisabeth West Fitzhugh, Archetype. ISBN 978 1 904982 76 0.

Blue pigments used in painting include some of the oldest used by man, and others that led the change to modern synthetic pigments driven by the arrival of chemistry in the eighteenth century. This weekend I look at two examples, today the queen of pigments, ultramarine, and tomorrow the first synthetic chemical, Prussian blue.

Originally made by crushing and grinding the semi-precious stone lapis lazuli, the cost of ultramarine has exceeded that of gold. Seen in paintings, it produces a rich slightly reddish blue which stands the test of time, as distinctive and effective today as when it was first used. And its use has a history of unmasking fakes and forgeries.

The sole source of lapis lazuli in Europe and the West were quarries in Badakshan, described by Marco Polo and now in Afghanistan. It appears that wall paintings made around 507-554 CE adjacent to the great Buddahs of Bamiyan were the first to have used the mineral as a pigment. It was then used in early Persian miniatures, and in early Chinese and Indian paintings too. Tragically, these wall paintings in Bamiyan, Afghanistan, were damaged by the Taliban in 2001 when the two statues were destroyed, and their restoration has made little progress since.

The powdered pigment had made its way, first along the Silk Road, then by sea, to traders in Venice by about 1300. By the Renaissance, it was established as one of the most important and precious of all the pigments used in European art.

Because of its beauty and high cost, ultramarine blue was used for the robes of Jesus Christ and the Virgin Mary. Duccio’s panels from the Maestà Predella, including this of The Healing of the Man born Blind, show this tradition in its earliest years, around 1307-11. As a pigment, it proved practical in egg tempera as here, and in oils, watercolour, and fresco.

Ultramarine blue has been found in the van Eyck brothers’ Ghent Altarpiece from about 1432 (above), and particularly in its most famous panel, The Mystic Lamb, below.

Sandro Botticelli’s early tempera on panel painting Adoration of the Kings from about 1470, apparently made with Filippino Lippi, shows two different blue colours and purple. He painted the purple with an opaque underpainting of lead white tinted with a red lake derived from madder, to create pink. That was then glazed with quite coarse particles of ultramarine blue, so the pigment was thinly dispersed.

Peter Paul Rubens used ultramarine blue widely in his magnificent triptych now in Antwerp Cathedral. In its centre panel, Descent from the Cross (1612-14), it has been found combined with indigo and other pigments.

In van Dyck’s Charity from 1627-8, its most obvious use is in the blue cape, where ultramarine blue was painted over indigo, applied as both a tint and as a glaze over the top.

Visit any of the larger galleries with substantial collections of paintings made before 1700, and you will see works with drapery that I can only describe as arresting in the brilliance of their ultramarine blue. One stunning example in the National Gallery in London is Sassoferrato’s The Virgin in Prayer from 1640-50. The Virgin’s cloak looks as if it was painted only yesterday, and that colour makes you stop in your tracks and draws you into the painting, like no other pigment can.

Given its importance, and limited supply, considerable effort was devoted to ensuring that natural ultramarine blue was of the highest quality, and alternative sources were sought. Deposits in the Chilean Andes, and near Lake Baikal in Siberia, weren’t developed until the nineteenth century, and attempts to make synthetic ultramarine proved unsuccessful until 1828, when Jean Baptiste Guimet was awarded a prize of six thousand francs for his discovery. Almost simultaneously, C G Gmelin of Tübingen discovered a slightly different method.

Commercial production had started by 1830, and it became known as French ultramarine, to distinguish it from the natural pigment. Although almost identical in colour and performance, there are significant differences between natural and synthetic ultramarine when tested in the laboratory. This has enabled the examination of paintings to determine the source of their pigment, and has brought some surprises. These most often relate to later overpainting during restoration. For example, two areas of much later painting have been discovered in the van Eycks’ Ghent Altarpiece.

Examination of Édouard Manet’s Corner of a Café-Concert, from 1878-80, has shown that he used synthetic ultramarine in its blue passages, for example.

Pierre-Auguste Renoir’s The Umbrellas, from about 1881-86, uses synthetic ultramarine in a methodical fashion. The first stage in its painting used only cobalt blue, but in its second stage synthetic ultramarine was applied extensively.

Vincent van Gogh’s A Wheatfield, with Cypresses (1889) contains synthetic ultramarine in its deepest blues, and in some areas of green, although it’s unusual to find ultramarine mixed to form green. Before synthetic pigment became available, this would have been far too expensive a way of making any significant amount of green, but once much cheaper pigment came onto the market, that became more feasible, if still unusual.

The ability to distinguish synthetic ultramarine, which didn’t exist before about 1828, and the natural pigment has proved important in detecting some forgeries. Only the most ignorant would attempt to pass off a painting made with synthetic ultramarine as being very old, but a few fakes fell at that hurdle.

Han van Meegeren was far too knowledgeable and cunning to be caught so easily. He used natural ultramarine, for example when he sold The Men at Emmaus (1937) to the Museum Boijmans Van Beuningen as a Vermeer. What no one knew at the time was that his ultramarine looked genuine, but had been contaminated with a small amount of cobalt blue, which wasn’t discovered until 1803-04, and was first used as a pigment in 1806.

In 1960, the modern artist Yves Klein worked with the paint supplier Edouard Adam to ‘invent’ a paint he termed International Klein Blue (IKB). Although its formulation is a secret, it’s almost entirely synthetic ultramarine blue pigment in a polyvinyl acetate binder.

Like all the best queens, ultramarine blue has an unnerving habit of revealing the truth.

Reference

Joyce Plesters (1993) Artists’ Pigments, vol 2, ed Ashok Roy, Archetype. ISBN 978 1 904982 75 3.

For all its toxicity, vermilion proved an enduring red, unlike less dangerous pigments such as crimson, with its natural origin.

People have dyed their clothes and other fabrics using vegetable colourants for as long as we have evidence. Dyes are quite unsuitable for use in durable paintings: instead of solutions of small molecules of colourant that work well applied to fabrics and paper, we much prefer to paint using pigments, in which the colourant is packaged and protected in much larger particles.

One of the early challenges in the history of art materials was the transformation of vegetable dyes into pigments, in a process generally known as laking. The need was simple: take a vegetable dye such as the crimson derived from Madder plants, and fix it into pigment particles that can be dispersed in gum solution for watercolour, or a drying oil medium.

Neither the Romans nor the Greeks appear to have solved this on any scale, but at some time between the Classical civilisations and the pre-Renaissance, someone discovered that aluminium salts will combine with the colourants in madder extract and make a pigment suitable for fine art painting, in madder lake.

Over time, many different recipes for the preparation of madder lakes were evolved. By using different species of Madder plant, adjusting the method of extracting the colourants from its root, and using different salts for the laking process, madder lakes covered a broad range of hues from pale purples through pinks to brilliant scarlet.

As a result, madder lakes were very widely used, and generally sought-after, except that they weren’t lightfast, even when protected in an oil paint film, and many faded rapidly, over months or just a few years.

Friedrich Herlin’s High Altar made for the church of St Jacob in Rothenburg in 1466 is one of the earliest paintings in which madder lake has been demonstrated. Its abundant reds seem to have stood the test of time, although because Herlin’s painting was normally stored with its wings closed, its madder lakes will have had limited exposure to bright daylight.

The two or three different shades of red used by Herlin in the panel of The Presentation of Christ in the Temple are still brilliant, although something odd appears to have happened in the blue robes of the Virgin Mary.

The Mass of Saint Hubert, the right hand shutter of the Werden Altarpiece from about 1485-90, has also retained its deep madder lake reds.

Madder red was mixed with a little lead-tin yellow for the sleeve (at least) in Altobello Melone’s Christ Carrying the Cross, dating back to about 1515.

Niklaus Manuel’s Demons Tormenting St. Anthony, on the left wing outside from the Antonius Altar of 1520, features several different reds, at least one of which contains madder lake as its main pigment. It also appears that some of those reds may have faded: Saint Anthony’s cloak looks pale and anaemic, for example.

Jan Vermeer’s Christ in the House of Martha and Mary from about 1654-56 is a good example of the use of madder lake by one of the Dutch Masters.

When industrial chemistry started to look for improved dyes and pigments in the nineteenth century, attention turned to the humble Madder, in an attempt to isolate the most lightfast components of its root extract, then to synthesise them on an industrial scale.

The main colourant, alizarin, was isolated in impure form in 1826, following which rose-red alizarin lakes became available. The other major colourant, purpurin, was more of a mystery, as little was found in fresh root extract, but it was generated during manufacture and storage; its purification took a few decades longer to achieve.

I suspect that the delicate reds in Henri Fantin-Latour’s Still Life with Chrysanthemums (1862) owe much of their colour to partially-purified alizarin crimson derived from Madder root.

Alizarin was first synthesised in about 1869, became available as a pigment in its own right from 1891, and was considered to be both more consistent in its colour and more lightfast. However, its lightfastness didn’t prove as good as had been hoped, and since the late twentieth century the fading of alizarin crimson has been used in lightfastness testing to demonstrate that sufficient light exposure has occurred. It has effectively become the benchmark for non-lightfastness.

Modern professional watercolour ranges, here those from QoR, often include a paint designated as Permanent Alizarin Crimson, which doesn’t contain alizarin or any other derivative of the Madder plant.

A few ranges, including Winsor & Newton Artists’ Watercolour Sticks, do still offer genuine alizarin crimson (PR83). Unless you are content for that colour to fade on exposure to light, you should avoid using it in any significant work.

This is true even in oil paints, where ranges such as Williamsburg’s offer a Permanent Crimson using a more lightfast pigment.

It’s a great pity that the crimson used by Vermeer and extensively by JMW Turner has such fugitive colour. At least we now have several excellent alternatives.

Reference

Helmut Schweppe and John Winter (1997) Artists’ Pigments, vol 3, ed Elisabeth West Fitzhugh, Archetype. ISBN 978 1 904982 76 0.

As a primary colour, red is essential to most palettes, but it has also proved technically challenging to find pigments that are both intense and lasting. This weekend I look at the history of two contenders, in vermilion and crimson, names also steeped in history.

There’s one red that looks as brilliant today as when it was first brushed out five hundred or even two thousand years ago. It’s a pigment known to, and used by, the Romans, and in ancient China was not only used extensively in art, but was scattered in graves. Vermilion is one of the most toxic pigments, and over the last century has been displaced by cadmium red and more novel organic pigments. Look at many paintings made before 1870, and their reds are likely to be dominated by vermilion.

For a long time, vermilion paint was made using powdered cinnabar, naturally-occurring mercuric sulphide, and is then technically known as cinnabar rather than vermilion. Its manufacture from liquid mercury was probably brought from China to Europe, since when much of the vermilion pigment used in Europe has been synthetic.

The main source of cinnabar, and of the metal mercury, in Europe were the mines at Almadén in Spain. These were used by the Romans, and until their closure in 2000 had produced more cinnabar and mercury than any other location. In 1563, deposits were discovered in Huancavelica in Peru, and they were the second largest source over the following three hundred years. Other important sources have been located in China, Slovenia, Italy, Mexico, and the USA.

The mining of cinnabar has long been recognised as hazardous due to its great toxicity, something known as far back as the Romans. Locked in pigment particles in oil paint it’s less hazardous than in water-based paints such as egg tempera; it’s wisest not to use cinnabar or vermilion in dry form, as in pastels, even with good respiratory and skin protection. Even with careful handling, pigment residues pose a serious threat to the environment.

The brightest of the reds in Duccio’s Transfiguration, from the Maestà Predella Panels painted in 1307-11, have the distinctive colour of vermilion. It is often associated with holy people, and holy objects, and contrasts with the other brilliant pigment of ultramarine, which is conventionally used in the clothing of the Virgin Mary.

Its one unfortunate habit is a tendency to blacken, by forming the black version of cinnabar known as metacinnabar. This tends to happen more often in the thinner, less protective paint films of aqueous media, particularly egg tempera, as shown in Nardo di Cione’s Saint John the Baptist, Saint John the Evangelist and Saint James from 1363-65. The lining of the clothing of the saint at the right uses vermilion, and has darkened in patches as a result.

Masaccio’s panel of Saints Jerome and John the Baptist from the Santa Maria Maggiore Altarpiece, from 1428-29, is another fine example of the use of a lot of vermilion (as cinnabar). The robes of Saint Jerome, on the left, may also show a little darkening in patches, but contrast well with the paler and pinker red of Saint John the Baptist at the right.

Cinnabar saw extensive and highly effective use by the van Eycks in The Ghent Altarpiece (c 1432). Because this was painted in oils, the chances of discolouration are much lower.

Botticelli used cinnabar in several passages in his Mystic Nativity (1500), where its persistent colour contrasts with his use of other red pigments, which haven’t retained their colour as well.

All the Masters and most other significant artists of the past used cinnabar, or vermilion when it was being manufactured in Europe by the early seventeenth century. Tintoretto was no exception, as shown in these two examples: Jupiter and Semele (1545) above, and The Origin of the Milky Way (c 1575), below.

Peter Paul Rubens’ centre panel of the Descent from the Cross (1612-14) in the huge triptych in Onze-Lieve-Vrouwekathedraal, in Antwerp, is one of the most spectacular demonstrations of the use of vermilion, and its lasting chromatic brilliance.

Rembrandt is another Master who used vermilion to great effect, here in the dress of the woman at the right, in his Belshazzar’s Feast (c 1635-38). The colour draws attention to her as she is so shocked as to empty the goblet she is holding in her right hand. A duller colour might have allowed this dramatic action to pass unnoticed by the viewer.

Aelbert Cuyp’s Hilly River Landscape with a Horseman talking to a Shepherdess from about 1655-60 is one of the few oil paintings in which darkening of cinnabar has become obvious. The pigment serves well in the huntsman’s coat, but has darkened in patches.

William Hogarth played on another common association of the colour red in the third painting, The Inspection, from his series Marriage A-la-Mode (c 1743). Although in English we usually refer to a scarlet woman, rather than a vermilion one, his use of vermilion here is effective in portraying the woman as a prostitute.

Vermilion remained popular well into the latter half of the nineteenth century, long enough for it to grace the paintings of the Pre-Raphaelite movement and the French Impressionists.

Although Claude Monet used just a few dabs and strokes of vermilion in his landmark painting Bathers at la Grenouillère (1869), he continued to use it well into the latter years of his career. By that time, though, the new cadmium reds were replacing vermilion, a process that is almost complete today, with cadmiums now being superceded by modern organic pigments.

Reference

RJ Gettens, RL Feller & WT Chase (1993) Artists’ Pigments, vol 2, ed Ashok Roy, Archetype. ISBN 978 1 904982 75 3.

Many yellow pigments in use, even into the twentieth century, have shown a pronounced tendency to fade. So when someone comes along offering you a ball of compressed powder that is an intense yellow, and appears more lightfast than alternatives, you’ll believe anything they say. It comes from the urine of cows? No worries, just tell me how much, and when can you deliver?

This seems to have been the story behind the introduction of Indian Yellow into European painting. It had a long track-record of use in and around the Indian sub-continent, where it had featured in watercolours and gouache, and buyers in Europe were only too happy to pay high prices for it when it became available.

This exquisite watercolour miniature showing a Mongol Chieftain and Attendants from the Gulshan Album now in the Freer and Sackler Galleries is a good example, from around 1600. Its yellows and greens have lasted those four centuries very well, and careful testing by Elisabeth FitzHugh has shown the unmistakable presence of the chemicals known to be diagnostic of real Indian Yellow.

The snag with European paintings is that so few works have been tested, and records are so scant, that we don’t even know when Indian Yellow was first used as far west as Europe.

Ernst Willers’ Grove Near Ariccia in the Evening Light (1873) is one of the few European paintings known fairly unequivocally to contain Indian Yellow, probably used to form its rich greens.

We know with rather greater certainty when Indian Yellow came off the market, as by the end of the nineteenth century supplies had essentially dried up. The claim is that, between the late 1500s and then, some Indian herdsmen fed their cows with mango leaves, collected the cows’ urine, and dried it to generate the pigment in balls of compressed powder, some of which still exist. In the nineteenth century, this was increasingly viewed as being cruel to the cows, and the practice was progressively eliminated.

Whether this story is accurate, or indeed the pigment ever saw much use, remains open to doubt. Certain claims, for example of a ban on the production of the pigment from 1908, can’t be verified and appear legendary. But there is evidence that some artists in both India and Europe used the pigment in their paintings.

Its successor Chrome Yellow is part of a family of pigments ranging from pale lemon to deep orange-red, and based on lead chromate, which had been ‘discovered’ as a mineral in the middle of the eighteenth century. Its use as a pigment wasn’t recognised until the early nineteenth century, when it became increasingly popular and versatile.

Initially, supplies were limited and it was expensive. As general commercial demand for the mineral increased, new sources of supply were found, and its price fell accordingly. During the latter half of the nineteenth century it was probably the mainstay yellow and orange in the palette of most painters.

The first evidence of the use of chrome yellow as a pigment in painting dates from just before 1810. Johann Friedrich Overbeck’s painting of Italia and Germania (or possibly Sulamith and Maria) was made in 1828, and is thus from the early adoption phase, when the pigment was expensive and encountered infrequently. Although Overbeck was restrained in his use of colours from orange through to yellow and green, he has achieved a subtle chromatic effect in the green fabric.

Carl Blechen seems to have used Chrome Yellow more extensively in his imposing View of Assisi, painted a few years later in 1832-35. By this time the mixture of Chrome Yellow with Prussian Blue had become known as Green Cinnabar or Chrome Green, although the chromium salt used was not itself green, of course.

By the time that Arnold Böcklin painted this, his first version of Villa by the Sea in 1864, Chrome Yellow had established itself as the standard. However, this is one of a relatively small number of works using the pigment in an almost encaustic mixture of resin and wax.

Chrome Yellow was widely used by the Impressionists and shown at the Salon, and is demonstrated well in Paul Cézanne’s famous painting of The Railway Cutting (c 1870). I believe that most if not all of the greens seen here rely on Chrome Yellow mixed with blue.

As some of the Impressionists, like Claude Monet, generated more income, they could afford to start using the newer and far more expensive cadmium-based pigments that were coming onto the market. Cadmium Yellow is also considerably more lightfast and durable than Chrome Yellow, so during the late nineteenth and early twentieth centuries, many painters switched away from Chrome Yellow.

Walter Crane’s Neptune’s Horses (1892) is one of the later works that apparently still relied on Chrome Yellow.

During the twentieth century, Cadmium continued to displace Chrome in pigments for paints ranging from lemon to orange-red. However, both are potentially environmentally damaging, and in this century more modern, less toxic synthetic organic pigments have been introduced as substitutes. Thankfully, as both Cadmium and Chrome pigments trap their toxic salts in insoluble particles, neither presents any danger to the careful painter when used in paint. For the pastellist, though, inhalation of pigment in dust is a more significant risk.

Chrome Yellow was one of the key colours of Impressionism, and features in many nineteenth century landscapes. No cows ever suffered in its manufacture.

References

NS Baer, A Joel, RL Feller & N Indictor (1986) Artists’ Pigments, vol 1, ed Robert L Feller, Archetype. ISBN 978 1 904982 74 6. (Indian Yellow)
Hermann Kühn, Mary Curran (1986) Artists’ Pigments, vol 1, ed Robert L Feller, Archetype. ISBN 978 1 904982 74 6. (Chrome Yellow)

As one of the primary colours, yellow is a vital paint for artists. For many centuries there weren’t any particularly good greens that were also enduring, so many oil and watercolour paintings have relied on the mixture of blue and yellow to generate most of their greens. This weekend I show and tell the stories of three of the yellow pigments that have featured in well-known paintings. Today’s is about one pigment that went missing from the palette for two hundred years, and tomorrow I’ll consider two other yellows with unusual histories.

For much of that period many of the pigments used in artists’ paints were closely guarded secrets. Their precise manner of preparation, even the source of their ingredients, were considered part of the craft of paint-making, whether performed by a supplier or in the artist’s workshop. On at least one occasion, this led to the loss of a pigment from the palette: Lead-Tin Yellow, widely used in many of the greatest works of art prior to 1750, vanished until its rediscovery in 1940.

Like several other pigments, Lead-Tin Yellow seems to have originated in glassmaking, and there’s some evidence of its use as a pigment in glass made as early as about 400 CE. Its earliest use in paintings probably dates back to Giotto in about 1300, following which it became extremely popular.

My earliest example is this painting in egg tempera attributed to Jacopo di Cione: Noli me tangere from around 1368-70. Examination of the brilliant yellow lining to Christ’s robe has shown that its pigment is Lead-Tin Yellow of type II. That is a variant consisting of a lead-tin oxide with free tin and silicon that’s more strongly associated with glass-making, and prepared slightly differently from the ‘purer’ type I.

Both types of Lead-Tin Yellow have proved robust and stable pigments in a range of different binders, including egg tempera and oils.

The centre panel of Rogier van der Weyden’s St Columba Altarpiece, showing the Adoration of the Magi, from about 1455, has been found to contain Lead-Tin Yellow in the rich yellow sleeve of the king in the centre. This is shown better in the detail below.

By about 1450, Lead-Tin Yellow type I was increasingly being used in paint. For example, the infant Christ’s lemon yellow dress in Ambrogio Bergognone’s The Virgin and Child with Saint Catherine of Alexandria and Saint Catherine of Siena (c 1490) has been found to contain this ‘purer’ type.

Another very similar painting by Bergognone, his The Virgin and Child from 1488-90, has not, as far as I can tell, been examined to test for the use of Lead-Tin Yellow, but I strongly suspect the infant Christ’s dress here contains the pigment too. This is shown particularly well in the detail below.

Although believed to be a stable colour, one of the more surprising examples of the use of Lead-Tin Yellow is in one version of Leonardo da Vinci’s The Virgin with the Infant Saint John the Baptist adoring the Christ Child accompanied by an Angel, better-known as The Virgin of the Rocks. The panel from the S. Francesco Altarpiece of Milan, painted between 1491-1508 and now in the National Gallery in London, is shown here.

The light brown lining of the Virgin’s blue cloak, shown in the detail below, contains Lead-Tin Yellow type I. The version in the Louvre, in which that lining is a bright yellow, doesn’t appear to have been reported on.

Yellow is a prominent colour in the paintings in Paolo Veronese’s series The Allegory of Love. In this the third, Respect from about 1575, Lead-Tin Yellow type II has been found in the primrose yellow impasto on the man’s tunic.

Veronese used type I in the first of the series, and type II in the third and fourth, suggesting that he used different sources of supply for his pigments over this period. The two types appear visually indistinguishable, and don’t seem to handle differently in oil paint.

Several of Peter Paul Rubens’ paintings, including his Hippopotamus and Crocodile Hunt from about 1615, have been found to contain Lead-Tin Yellow, although I don’t know which type he used.

Another fine example of the extensive use of Lead-Tin Yellow, here of type I, is in Rembrandt’s Belshazzar’s Feast (c 1635-38). Many of Rembrandt’s paintings have been found to contain the pigment, but here it has been applied in thick impasto to model the highlights on Belshazzar’s cloak.

Rembrandt here used a double ground, over which he applied earth pigments before applying the uppermost layers of lighter colours, including Lead-Tin Yellow, to model the detail. These are shown in the detail below.

Jan Vermeer is another of the Old Masters whose paintings often contain Lead-Tin Yellow. In The Milkmaid (c 1660), for example, it accounts for much of the pale yellow of the woman’s bodice.

What happened next is rather strange. During the first half of the eighteenth century, Lead-Tin Yellow declined markedly in popularity, and by 1750 it appears to have been replaced by other, sometimes less stable, pigments, including Naples Yellow (highly toxic lead antimonate). Once replaced, the recipes for its manufacture appear to have been lost, and its use was forgotten.

During the eighteenth century, there were also changes in the supply of pigments and paints to artists, and by the nineteenth century most were sourced from specialist colourmen, who appear not to have known about Lead-Tin Yellow as a pigment. By the time that commercial manufacture of oil and other paints became widespread in the late nineteenth century, the pigment had been long forgotten. This was aided by uncertainty over its traditional name, which led to confusion with the pigment Massicot (lead oxide or Lead Yellow).

It was Richard Jacobi, working at the Doerner Institute in Munich in 1940, who stumbled across the pigment when analysing yellow paints in Old Master paintings. He reported his radical findings in 1941, and from the late 1940s and 1950s onwards paint analyses looking for it have been performed quite widely, and have found its extensive use in works between 1300 and 1750. Since then it has even been re-introduced in some commercial paint ranges.

Reference

Hermann Kühn (1993) Artists’ Pigments, vol 2, ed Ashok Roy, Archetype. ISBN 978 1 904982 75 3.