Tip:
Highlight text to annotate it
X
I'm Philip Ball and I'm a freelance science writer.
My lecture is about colour and chemistry and art.
It's specifically about how the invention of new colours by chemistry throughout the ages
has affected the way that artists have made use of colour.
It brings out the fact that you can see very definite stages in the history of art
where the availability of new colours completely transformed what artists could do
and changed the styles of painting as well as the colours of painting.
I want to show how these changes in art were linked to advances in chemical technology
whether it's in ancient Egypt or in 19th-century Europe.
It's because of these technological changes, which provided
not just colours but all sorts of daily materials,
that sometimes art has changed what it has done.
I want to start here: this exhibition happened three years ago.
It was an exhibition of Van Gogh's work at the Royal Academy.
In particular, it showed a lot of Van Gogh's letters.
It was praised by several reviewers as having 'revised' our view of the artist.
Rather than showing him as painting in a 'crazed frenzy',
as the romantic legend would have us believe,
his letters showed him to be rather thoughtful and methodical about his technique.
Now this was no surprise to anyone who already knew about the wonderful letters
that Van Gogh wrote to his brother, Theo.
They revealed a passionate man, but someone passionate not so much about love and death
so much as about art.
In particular, about the techniques and materials of art.
One of the things that inspired Van Gogh most were the colours that he used,
especially the new colours that had only recently become available in his time.
In one letter to Theo he wrote this:
"I've got new ideas and I have new means of expressing what I want
because better brushes will help me and I'm crazy about those two colours: carmine and cobalt."
"Cobalt is a divine colour and there is nothing so beautiful for putting atmosphere around things.
"Carmine is the red of wine and it is warm and lively like wine.
"The same with emerald green; it is bad economy not to use these colours.
"The same with cadmium."
This focus on materials isn't unusual among artists;
Van Gogh's friend Paul Gauguin, the subject of another recent blockbuster exhibition - this one at the Tate modern,
spent his time on Tahiti, fretting not so much about metaphysical questions of
'where we're from' and 'where we're going' or about *** relations
that he had with the Tahitian women,
but about the very prosaic difficulty of getting hold of the paints that he needed.
I think there's a metaphor here for the way we traditionally think about art.
Art historians have tended to analyse paintings in intellectual terms,
asking what the artist is trying to say, what feelings is he or she trying to convey?
But painters themselves are more often concerned with the practical issues of creating a painting.
One of the things that preoccupies them most is physical paint.
Take a look, for example, at this painting by Wassily Kandinsky.
It confronts us will all sorts of questions about style, form and intention,
such as whether these shapes have particular meanings
and why Kandinsky was led into this abstract form of expression.
But I'd suggest that the first thing that strikes you about this picture
is the vibrancy, the richness and exuberance of its colours.
It's become rather rare for art critics and historians to ask
where these colours actually come from and how their availability has influenced what's depicted.
We take these colours for granted now.
You can walk into an art shop and find rack upon rack of them.
If you look closely at the labels,
you'll find that many of them contain chemicals with complicated and daunting names
like quinacridone and phthalocyanine
and a chemist will tell you that these are the products of the modern chemical age.
So, were they available to Kandinsky in 1913?
How about Monet, or Turner, or Rembrandt?
I'm going to look at this issue of how art got its colours.
In particular, I want to raise the question:
how has the invention of new colour affected the directions that art has taken?
That might seem a little strange to study art by looking at its materials,
but that wouldn't have seemed strange at all for painters in the Middle Ages or the Renaissance.
They were deeply engaged with their materials
and this was out of sheer necessity because they knew
they would have to make their own paints
and they knew that the quality of their art depended vitally on the quality of these materials.
Although that's still true today,
few contemporary artists have a comparable relationship
with the physical nature, the characteristics of the medium they use.
One suspects that there's a perception of something almost vulgar
about these tangible aspects of art.
This means not only that some artists have undertaken
ill-informed and sometimes disastrous experiments with paints in modern times,
but that art itself is in danger of losing touch with its roots as a practical craft.
The most ancient art that we know of,
painted 15 millenia ago in the caves of Lascaux,
used pigments that were dug straight out of the earth.
These were ground up minerals, such as red and yellow ochre and chalk,
and these so-called 'Earth colors' are generally rather dull.
The ochres are iron-rich minerals, chemically similar to rust.
For black, cave artists used charcoal.
So the most common colours were those that nature offered most abundantly.
These were black, white and this kind of dirty red/yellow.
Now in 1969, two anthropologists, Brent Berlin and Paul Kay,
claimed that colour words appear in all languages in the same sequence.
Some Aboriginal languages distinguish only two colours: black and white.
Others have three: black; white and red.
What Kay and Berlin said is that
there's always the same sequence with which new words are added.
After black, white and red, you always get either yellow or green.
Followed by the next of those two.
This quartet of black, white, red and yellow,
corresponds to a kind of universal four colour scheme.
You'll never find languages with terms for just red, yellow and blue.
It seems unlikely to be a coincidence that these four basic colours
are the ones that nature offers most readily.
The Egyptians used these pigments too, but they had a broader palette.
Egypt in the third millennium B.C had a surprisingly sophisticated chemical technology,
because this was a product of the crafts that were central to everyday life and to religious life.
In fact, in Egypt artists were priests and art was considered a devotional practise.
Artworks were thought to acquire a supernatural power
through religious ceremonies and so the production of pigments to make them
was a socially important task.
One of the most renowned pigments of the ancient world
was Egyptian blue,
which was made by grinding up a copper-containing compound.
Chemically it's calcium copper silicate.
This was an artificial substance;
it was made by melting sand together with copper minerals and chalk,
probably discovered as an off-shoot of
the manufacture of blue-glazed stone called faience,
which were first made in Mesopotamia around 4500 B.C.
Faience was used for decorative purposes
and it stimulated experiments with materials and with the design of kilns
that probably also led to the discovery of glass
and to the discover of how to smelt copper, how to extract copper from its minerals,
which stimulated the beginnings of the Bronze Age.
This blue pigment arose by chance as a side product
from a technology developed for making something else entirely.
This is a common pattern for pigment discovery which recurs right through to the 20th century
Without the social demand for substances such as glass, soap, metal, dyes and plastics,
it's unlikely that many of the technologies for pigment manufacture
would have evolved, or would have been economically viable.
So the artist's palette is partly a by-product of industrial technology.
The Egyptians also knew how to use simple chemistry
to make other artificial colours: artificial whites, yellows, reds and greens.
Such as verdigris, which is made by letting vinegar fumes corrode copper.
So their colour scheme was really quite rich.
The Greeks inherited a lot of this technology,
but they didn't necessarily use all of these colours.
Some of the most renowned painters of classical Greece,
the period between about 600 and 400 B.C.,
such as Apelles, the court painter of Alexander the Great,
they chose to restrict their pallets to just four colours and sure enough,
these were those original four: black, white, red and yellow.
Nearly all great painting has now been lost.
But here's a Roman mosaic from Pompeii,
which reproduces and original Greek painting.
It's actually a painting of Alexander the Great,
and it gives you an impression of the limited palette that the Greeks used.
It's not clear why this four-colour palette evolved.
One idea is that as the Greeks moved beyond the flat, two-dimensional pictograms
that the Egyptians used and started to depict three-dimensional shading,
they found it difficult to achieve a harmonious balance of colour
if they used too many colours.
But whatever the case, this austere four-color palette
was eventually deemed to be the proper, dignified choice for all serious artists.
This was a prejudice that persisted in Imperial Rome.
You can find Pliny in the 1st century A.D. condemning artists
who use the bright, so-called 'florid' colours that could be imported from the East.
These colours became available from places like India
ever since Alexander's conquests in the East.
Pliny feared that the sensuousness of these Oriental colours
would corrupt the supposed purity of artistic expression that was developed in ancient Greece.
Unfortunately for Pliny,
public taste was more vulgar than that.
It delighted in bright colours and whatever he said
it didn't stop craftsmen from using bright colours for interior decorating.
You can see that from some of the surviving murals at Pompeii.
Unfortunately these mural techniques, used in the ancient world,
don't tend to preserve the colours well.
Once they're exposed to sun and to air they discolour, or they fade or flake off,
and this has left a lot of these buildings and statues drab and plain.
They give the impression that the Classical World
was a much more drab and pale place than it actually was.
Chemical technology thrived in what we have in the past labeled the Dark Ages,
particularly in the 8th and 9th centuries.
This happened not in the traumatised Christian West,
but in the Islamic Middle East,
where Arabic scholars mixed Greek philosophy with the practical skills
that flourished in Alexandrian Egypt.
These were blended together in the art of alchemy.
Alchemy is still widely misunderstood today.
Either it's seen as a misguided or a fraudulent attempt to make gold,
or as some kind of metaphor for a kind of spiritual transformation.
Some alchemy was undoubtedly done by tricksters,
or deluded gold makers,
but it's now generally regarded by science historians as having broader objectives
and in fact, that it's really a kind of pre-scientific chemical technology.
The Italian craftsman, Cennino Cennini,
wrote a craftsman manual around 1390 describing
many of the pigments that were then available
and how to make them, or how to get a hold of them.
He makes a lot of mention of alchemy
and this isn't some esoteric or mystical art,
it's simply a convenient manufacturing process for his colours.
It's no coincidence that alchemists were making colours for artists
because colour is central to the process of alchemy.
To make the philosopher's stone,
the substance that could allegedly transform base metals into gold,
one had to conduct chemical reactions that would take the raw materials
through a specified sequence of colour changes.
So it's not surprising to find the alchemists focusing their attention
on the substances that offered a wide range of different colours.
That turned out to be the same materials that artists would be using.
Take lead, for example,
it starts off as this dull, uninspiring stuff,
but it was known since ancient times that if you exposed
lead metal to the fumes of vinegar and animal dung it turns white,
owing to the formation of lead carbonate.
This was known as white lead.
It was the painter's finest white pigment, right up until the 19th century.
If you roast this white lead carefully in air,
you can convert it to lead tetroxide, which is red.
This pigment, simply called red lead,
was used in the classical world at least since the 2nd century A.D.
Cennino Cennini says that it is manufactured simply by alchemy.
In Latin it was known as minium.
Its extensive use in Medieval illuminated manuscripts
is what gives us the word 'miniature'.
It's purely coincidental that these works tended to be small,
they had to be small to fit on the page.
The Indian and Persian miniatures of the 17th to 19th centuries
also use a great deal of red lead.
They're finely detailed, but there's nothing small about them at all.
Further roasting of red lead can lead to a yellow material,
lead monoxide, or litharge.
This was used in the Middle Ages as a pigment called massicot.
To us there's nothing extraordinary about these reactions of lead with various gasses.
To the alchemists, they would have been seen as evidence of some fundamental change
that was purifying the lead, bringing it close to the colour of gold.
Yet the finest red pigment of the middle ages was, for the alchemists,
perhaps the finest substance of all.
The Islamic alchemists had the idea that all metals are
composed of two basic substances, or "principles": sulphur and mercury.
These alchemical principles aren't exactly the same as the sulphur and mercury
that you can get from minerals dug out of the Earth.
Nevertheless, if you do combine those two elements -
this yellow sulphur, which exists in the elemental form in nature,
and the liquid silvery metal mercury -
if you combine them together and heat them up, something miraculous happens.
They combine to form a hard, black-ish red material, mercury sulphide,
which, when it's ground up finely, turns out to have a glorious red colour
and painters knew this as vermilion.
The 11th century Benedictine monk, Theophilus, describes how to make vermilion
in his own craftsman's manual and he gives a very detailed
account of how to do this, which is really as detailed
as pretty much any description of a chemical synthesis in the 18th or 19th century.
Cennini can't be doing with going through all of that,
he simply advises the painters to go and get their vermilion ready-made from the alchemists,
but he warns them not to get it ready-ground like this
because some alchemists had a tendency to mix it up with brick dust to make it go further.
The art historian Daniel Thomson has claimed that
the invention of vermilion was the central innovation of medieval art,
he says this:
"No other scientific invention has had so great and lasting an effect
upon painting practise as the invention of this colour.
"Given abundant vermilion, the standard of intensity
in the painter's palette automatically rises.
"Equally brilliant blues and greens and yellows were required to go with it.
"If the middle ages had not had this brilliant red,
they would hardly have developed the standards of colours which they upheld,
and there would have been less use for the inventions of the other brilliant colours,
which came on the scene in and after the 12th century."
We can see how much Medieval artists loved vermilion
by the way they would sometimes apply it in great swathes,
in great blocks of colour for everyone to marvel at.
Medieval art, with its cartoon-link quality and its lack of perspective
and its blocks of unshaded colours, sometimes looks odd to us,
but we have to remember that the aim of the Medieval artist was not to paint realistically.
The subjects were almost always religious and the artists,
who were often themselves monks,
believed, like the Egyptians, that paintings had a symbolic, religious power
and that this was enhanced if one used the finest materials
and displayed them unmixed with anything else
So Medieval works are rich in fine materials like this - like vermilion -
and also gold leaf .You can see gold leaf in the surrounding in this painting.
Then also in the later Middle Ages, in a still more wondrous pigment.
That's this one: ultramarine.
Cennini says of it:
"Ultramarine blue is a colour illustrious, beautiful and most perfect beyond all other colours.
"One could not say anything about it, or do anything with it,
that its quality would not still surpass."
As its name implies, ultramarine came from over the seas
because the mineral from which it was made
was not known anywhere in the West at the time
it is prepared from the mineral lapus lazuli.
This is a blue stone that at that time was found in only one place in the world,
in some mines in what is now Afghanistan.
For centuries, all of Europe depended on
these remote Afghan mines for their most precious pigment.
It cost more than its weight in gold.
Ultramarine was precious not just because it was a rare import,
but because it was very laborious to make.
Most mineral pigments are made just by grinding up the mineral into a powder,
but if you do that with lapus lazuli, the results are disappointing
because there are impurities in there and they turn it a grey-ish colour.
So those had to be separated from the blue stuff,
and that was done by mixing the powdered mineral with wax
and washing it and kneading it again and again in water
to flush out the blue stuff.
It was a very laborious process of preparation
which also contributed to its cost.
In most of the altar pieces of the Middle Ages
the *** Mary is shown in blue robes.
Here's an example from Duccio in the 14th century.
Various art theorists, even in modern times,
have attempted to explain the symbolic significance of this blue.
They say that it conveys humility or virtue.
But the main reason for this choice of colour is that
the artist would naturally have lavished the precious pigment
on the most holy aspect of the painting.
So, you can see that art can become harder to interpret
if you ignore the materials that it's made from.
So then, ultramarine, vermilion and gold leaf can be considered
the primary blue, red and yellow of the middle ages,
they were the most precious paints that a painter could acquire.
Some altar pieces use little else,
but by the 15th century, as we approach the period of the high Renaissance,
things were different.
This is how they were different: this is Titian's Bacchus and Ariadne
painted in 1523, and it's one of the most radiant images of Western art.
I think it shows why Titian is considered to be on of the finest colorists of all time.
You can see at one that this is a completely different sort
of painting than those from the Middle Ages.
There are many reasons for this;
we can see now people and places depicted realistically,
which is to say in an attempt to show they would look
if you were an observer actually in this scene.
So light, shade, perspective, proportion and anatomy, all of these are accurately observed.
This is the key feature of Renaissance humanism,
where actual human experience became the
central concern of artists and writers.
So it wasn't any longer sufficient to produce
the styallised, iconic works that
just paid lip service to the shapes and the forms of the real world.
So Renaissance artists instead put the viewer right in to the picture.
This meant that the materials of the painter no longer had the symbolic
values that they had in the Mddle Ages.
Ultramarine was prized now simply because it was a beautiful and pleasing colour
and also because it showed off the wealth of the patron who had paid for the painting
and not so much because its expense made it some kind of devotional offering to God.
Gold leaf gradually disappears from use during the 15th century
because no matter how costly it was,
that counted for nothing if it didn't produce a realistic effect.
Painters instead began to mimic gold using yellow, white and brown pigments.
Titian's paints are also totally different from Medieval artists.
Pigments have to be mixed with some fluid binding medium to make them into a paint.
In the Middle Ages that binder was often egg yolk.
But Titian and his contemporaries mixed their colours with oils.
This oil painting technique was perfected in northern Europe
in the early 15th century by artists such as Jan van Eyck,
and they were gradually adapted by the Italians from about the middle of that century.
In the earlier so-called egg tempera method
the paints dry very quickly.
But oils are much slower in drying and this meant that
colours could be blended and mixed
and so it permits the soft shadows and the subtle shading
that we see in Renaissance art.
Now the use of oils also compelled a change in pigment use
because some colours look different when they're bound in oil
from when they're bound in water or egg yolk
because these binders have different refractive indices.
In particular, ultramarine and vermilion are both more
transparent and less brilliant in oil.
This meant that painters had to adulterate these colours by
mixing a little bit of white in there to make them opaque.
This began to erode the mystique that colours like ultramarine had.
As a result, artists began to feel more free
to use a wider range of blues in their works.
The art historian Paul Hills says that:
"Blue, by the 15th century, was moving away from its association
with starry night - the vault of the heavens -
to the changeful sky of day."
So this was a change in colour use instigated by the
physics and chemistry of the materials.
But there were other reasons why Titian and his contemporaries
had a wider range of colours available to them
than most Medieval artists.
Titian lived and worked in Venice which,
along with Florence, was the artistic capital of Renaissance Italy.
But Venice was also a port, where many of the
rare spices, textiles, food and pigments arrived from the East.
So the Venetian artists had their first pick of these colours
and they made abundant use of it and Venetian art is particularly colourful.
In Bacchus and Ariadne,
Titian uses just about every one of the pigments available
in the early 16th century.
In doing so, he provides us almost with a map
of the state of 16th century chemistry.
The brilliant sky here is ultramarine and so is Ariadne's robe.
But the sea, you can see it has a kind of greenish tint.
This is a different blue mineral called azurite,
it's a copper mineral.
It had been known since ancient times and there are deposits of it
in Europe, which helped to make it cheaper.
Imported ultramarine rarely made its way all the way to northern Europe,
at least at an affordable price.
Ao azurite is the main blue of the works of the
Dutch and German artists of the Renaissance.
There's vermilion here too in Ariadne's scarf.
But there's also another kind of red pigment here called red lake.
This is made from red dyes, which are organic materials.
They are extracts from planets and from animals
so some red lakes were made from the extracts of Brazil wood and madder root,
others came from animals like the cochineal that was made up from ground up dried beatles.
These dyes were converted to so-called lake pigments by dissolving the
colouring agents in water and then fixing them on the surface of fine white particles.
This procedure was known in the Middle Ages
but wasn't really perfected until the Renaissance
These red lakes are darker and richer than vermilion,
There's a common red lake known as kermes,
which is the root of our word crimson.
Lakes are also translucent when mixed in oils
and Renaissance painters often used them as translucent glazes
to cover over other colours to give these rich flesh tones,
or to make purples by glazing red over blue.
There are other yellows in here too.
Renaissance yellows were typically compounds of lead, tin and antimony.
The Egyptians had known how to make some of these too,
but in Bacchus and Ariadne there's also a brighter yellow pigment,
which is called orpiment.
This is arsenic sulphide - the name orpiment simply means 'pigment of gold'.
It can be found naturally in a mineral form, but a better
quality of pigment could be made artificially through alchemy.
Also, because it contains arsenic it's highly poisonous.
Some painters avoided using it for this reason.
Cennini warns anyone who uses it to look out for yourself.
He says make sure you don't get it in your mouth by licking your brush.
One northern painter who did use this stuff was Lucas Cranach.
That's probably because Crannach was himself an alchemist, a pharmacist.
He ran a pharmacy and so was very knowledgeable about the methods of alchemy.
Also in this picture, there's an orange pigment;
the only pure orange pigment that was known until the 19th century.
It's a pigment called realgar, which is a different form of arsenic sulphide.
This also occurs naturally and it was imported into Europe
through Venice from Romania and the East, and again,
it's very expensive and poisonous so rarely used in European art.
Now something happened to colour during the 17th and 18th centuries.
Rubens often painted as brightly as Titian
but we remember this period more for the subdued pallets of people like
Rembrandt and Van *** and Poussin.
European art went through a period of subdued colour at that time,
and there wasn't much innovation in pigment manufacture during this period.
It's interesting that several of the new colours that did appear
were the autumnal colours that typify painters like Rembrandt.
The prevailing attitude of the connoisseurs by the early 19th century
was summed up by Sir George Beaumont, who was
himself an artist and a patron of John Constable,
and claimed that "a good picture, like a good fiddle, should be brown".
Here is Constable, apparently eager to please his patron, I think.
If these pictures weren't brown enough already,
Victorian conservatives often made them more so, by giving them a coat of muddy varnish.
In Constable's defense, he's said to have protested against what Beaumont said
by taking a violin and placing it on grass to
show how different the two colours really were.
Nevertheless, he clearly respected the convention that expected artists
to tone down their colours.
In fact, he was considered for his time an innovator
with an unusually bright palette.
I think that tells us something about how truly murky colour has become
by the early 19th century.
I want to have a look at some of these autumnal colours.
For baroque painters who liked their works dark and golden,
there was a substance called Cassel Earth.
This was a peaty substance with a warm brown colour.
Van *** liked it so much that it became known by his name, Van *** brown.
There was stuff called bitumen.
It was literally that: an appalling, tarry, brown pigment that never dried
and has ended up ruining several 19th century paintings such as this one
Géricault's Raft of the Medusa, which is more or less
never exhibited now because it's in such a terrible state.
There was also a yellow substance that was imported from India,
and this was quite mysterious, it was just known as Indian yellow.
It was imported by the Dutch and it was used by Rembrandt a lot
and for a long time no one knew what it was made of.
It turned out, in the late 19th century, it was found that it was made from
the urine of cows fed exclusively on mangoes.
But in the late 18th century, things began to change,
because a new rainbow began to spread across the artist's palette.
This was the golden age of chemistry.
It was when new elements were being discovered all the time
and the French chemist Antoine Lavoisier was
starting to make sense of chemical transformations
largely through his discovery of the element oxygen.
That discovery itself it contentious and some claim that the first person
to see oygen was actually the Swedish apothecarist, Carl Wilhelm Scheele.
Scheele was certainly one of the greatest experimental chemists of his time.
H isolated hydrogen and barium and chlorine.
In 1775, Scheele discovered a green substance whilst he was experimenting
on arsenic compounds.
This was copper arsenite, which soon became used as a green pigment
simply called Scheele's green.
This was brighter than any of the earlier pure green pigments.
Until then, many painters had to make greens by mixing some blue with some yellow.
But Scheele's green was itself eclipsed by the discovery in 1814 of
a new, even more attractive arsenic-based green pigment,
which became known in england as emerald gree', or Paris green.
Unfortunately this too was poisonous,
These arsenic greens, if they were exposed to dampness,
they decomposed into a toxic arsenic-containing gas
But because they were quite cheap to manufacture,
emerald green and Scheele's green were used not only as artist's materials,
but also as commercial colours, as household paints, and on patterned wallpaper.
This made damp rooms potential death traps.
Around the middle of the 19th century, there were fears expressed that
young children were being killed by the deadly fumes emanating from their bedroom walls.
Some people believe that Napoleon's death, in exile on Saint Helena,
was also hastened this way.
But perhaps the most important innovation in artist's colours in the 19th century
stemmed from the discovery, in the late 18th century
of a bright red mineral from Siberia called crocoite, or Siberian red lead.
In the early 19th century, the French chemist Nicolas Louis Vauquelin
investigated this mineral and found that it contained a new metallic element
whose compounds were brightly coloured and for that reason, he gave it a name
in Greek meaning colour, chrome.
Of course now we know this element as chromium.
Crocoite is a mineral form of lead chromate.
When Vauquelin made this same compound synthetically,
he found that it had a bright yellow colour.
This was a very cheap pigment to make and it was
used commercially. It was used to paint carriages,
which is kind of a nice foreshadowing of its use on the yellow cabs of New York today.
Vauquelin found that he could also make a different form of lead chromate that was orange.
This was the first orange pigment since poisonous realgar,
and chromium oxide was a green colour, which if you made it in a way
that incorporated a little water into the crystals, it provided a very rich
green pigment in England called veridian.
There was a flood of these new colours in the early 19th century.
In 1817, the German chemist Friedrich Stromeyer discovered a new element called cadmium,
which was a byproduct of zinc smelting.
He found that cadmium could be combined with sulphur to
make bright yellow and orange pigments called
cadmium yellow and cadmium orange.
In the early 20th century, a red version of this pigment became very popular too;
Matisse was particularly fond of it.
In the late 18th century, the French government considered
pigment manufacture now so commercially important that it
appointed some of its leading chemists to discover new pigments.
The government asked Louis Jacques Thénard to look for
a synthetic substitute for ultramarine, which was still expensive.
In 1902, Thénard found how to make a rich blue colour from cobalt,
this was simply known as cobalt blue.
Cobalt turned out to offer several other colours too.
In the 1850s, a yellow pigment called aureolin became available in France.
That was soon followed by the first ever pure purple pigment, cobalt violet.
A sky blue pigment containing cobalt was also later invented,
which became known as cerulean blue, from its resemblance to the colour of the sky.
But what painters really wanted in their blues was a cheaper form of ultramarine itself.
In 1824, the French Society for the Encouragement of National Industry offered a prize
for the first practical synthesis of ultramarine.
It's a complicated stuff to make,
partly because its blue colour comes not as in most
pigments from the presence of a particular metal,
but from the presense of sulphur in the crystal structure.
It took only four years in 1828 for a Frenchman, named Jean Baptiste Demay
to claim this prize by making synthetic ultramarine,
which thereafter became known as French ultramarine.
So pigment manufacture was big business,
it wasn't any longer the cottage industry that
it was when apothecaries were making this stuff.
Factories were set up in the 19th century to make and to grind pigments
and some of them sold these pigments in pure form to artist suppliers
who then mix up the paint for their customers by mixing the pigments and oil.
But some pigment manufacturers like Reeves and Windsor & Newton in England
started to provide ready made oil paints,
which from the 1840s they sold in collapsible tin tubes.
This meant that painters themselves were becoming ever less familiar
with what it was that they were buying
and they had no way of assessing the quality of this profusion of colours.
So a new breed of professional began to appear called "the colour man",
who knew what the artists needed, but also had some chemical knowledge
that enabled them to assess the quality of materials.
In England, the foremost colour man of the 19th century was George Field.
He supplied paints to Turner and to the Pre-Raphaelites
We can see what sort of difference these colours made by looking at John Millais' Ophelia.
Compare this picture to Constable, just less than 20 years earlier.
See how different in particular the greens are,
how vibrant they have become.
In fact they were too vibrant for some critics.
One of them called the greens here "unripe enough to cause indigestion".
But these painters relied on Fields' judgment about whether or not a colour was reliable,
for example whether it would fade or discolour rapidly on the canvas.
Thanks to Field in particular, Turner was able to acquire these new colours
almost as soon as they were invented .
He was among the first painters in England to use cobalt blue
and emerald green and veridion and chrome yellow and others.
This was still a gamble because even with the assistance of someone like Field,
some of these colours might end up losing their brilliance over several years.
In fact some of Turner's works have suffered this way.
But all the same, Turner remains one of the greatest innovators in colour
and he brought a blaze of Venetian brightness to the dour palettes of early 19th century.
You can see that here, this is his painting, Ulysses Deriding Polyphemus,
which was considered shocking by some contemporary critics.
One of them said of this picture that it was "a specimen of colouring run mad".
Positive vermilion, positive indigo and all the
most glaring tints of green, yellow and purple.
Another, I think more perceptive observer, compared Turner to a "Rembrandt born in India".
Turner's use of colour was an important influence on the Parisian Impressionists
such as Monet, who came to London to see his work.
The Impressionists made equally avid use of these new colours.
The shock of seeing their work wasn't just that of seeing a new style of painting,
without the clear edges and the smooth finish
that the French Academy of fine arts preferred,
but also of seeing colours that had never been seen before on canvas.
In this picture, Boating on the Seine by Renoir,
apart from the traditional lead white, there are just seven pigments in here
and all but the reds are these modern synthetic
colours: cobalt blue, veridion, chrome yellow, lemon yellow,
which is a another chromate colour, and chrome orange.
Some of them are applied unmixed, straight from the tube.
In particular, with the placing of these very rich colours
so that the complementaries stand next to each other, the blue and the orange
complementary colours stand against each other and provide this very rich contrast.
The Impressionist style shaped the early work of many of the most important
painters of the modern age.
Cézanne began as an Impressionist,
and Van Gogh's work was transformed when he came to Paris and saw these paintings.
They gave him inspiration to use bold, unmixed new colours with glaring brilliance
like this with these harsh dissonances in this work, called The Night Cafe,
Van Gogh said that: "I've tried to show that the cafe is a place where one can ruin oneself
go mad, or commit a crime."
Henri Matisse was also an Impressionist early in his career
but he made later use of these pigments to even more stunning effect
as the figure head of the movement known as the Fauves,
a French word meaning "wild beast", which reflected their uninhibited use of these wild colours.
Fauvism made colour a central constructive component of art
and Kandinsky initially painted in this Fauve style and he went on
to try to discover a universal emotional language of colour itself.
None of this would have been possible without the development of the
vibrant new pigments in 19th century.
This explosion of colour wasn't just confined to art;
as chemistry blossomed it brought colour into the wider world,
especially when in the mid-19th century chemists discovered how to make new dye
from the aromatic hydrocarbons found in coal tar,
which was the residue of gas lamp burning.
These new dyes created very garish fashions.
The 1850s in particular became known as the purple decade,
as you can see reflected in this painting here.
I just wanted to give a little word of caution here
because when I was finding some of these images online.
If you do a search for something like this you'll find images like this coming up.
It's just a reminder of how dependent upon whatever technology you're using
the colours that you see are going to be.
There's a problem with reproducing colours accurately.
This picture was painted in the year that the first coal tar dye was discovered.
It was discovered by William Purkin, who at that stage was just a teenager
at the Royal College of Chemistry in London.
He'd been set the task of trying to synthesize quinine,
the antimalarial drug.
But instead he found that he made a kind of a brown
gunk which just settled at the bottom of his flask.
He found that he could extract from this a brilliant purple colour,
which turned out to be a very effective dye for silk.
He managed to persuade his brother and his father to set up a business with him.
He quit his studies and set up a business in Harrow,
a factory to manufacture this colour which became known as mauve.
This began the whole chemical industry.
So these coal tar dyes started to come one after another
and following that chemists found ways to make synthetic versions of natural dyes,
such as the colorance in madder red and in indigo.
This meant that the dye cultivating industries in the European colonies collapsed.
But the chemical industry thrived and many of the chemical giants of today,
Hecht, BASF, AGFA, Bayer, Ciba-Geigy all began their lives as colour manufacturers.
This is one of the early dye colour charts of the Bayer company.
Now the pigments of modern times encode their own stories
about how art evolved in the 20th century
and if I had time, I'd say something about the
Dayglow colours of Andy Warhol or Roy Lichtenstein,
or how people like Frank Stella began using commercial paints.
They just went into the paint shops and bought whatever was available
and used them for their art and so their palettes
were at the mercy of what commercial colour makers
were producing for completely different purposes.
I want to finish by talking about a little parable really
about chemistry and colour in art,
which is the story of the world's most beautiful blue.
It's a story about the French artist Yves Klein,
who was never a painter in the league of Rembrandt, Turner or Titian,
but who is remembered for one thing,
which was international Klein blue,
which he used for a series of monochrome paintings in the 1950s.
Klein believed, and in fact he then went on and did himself,
that painters would eventually paint in just one single colour,
that colour itself would be all that you needed to say.
Klein's blue here is nothing other than ultramarine.
It's actually just synthetic ultramarine.
But ultramarine never looked like this before
and you can't even do it justice in a reproduction like this,
you've got to see the originals because the quality of it
is all about the texture, the lustre of the material
because Klein realised that if you look at ultramarine powder,
it has a real lustre to it that you lose
when you mix with a binder.
He wanted to try to preserve that lustre with some kind of binder.
In 1855 he found his answer.
He found that a synthetic fixative resin
manufactured by the Rhône-Poulenc chemicals company
could be made to act as binder
that retained this chromatic strength of ultramarine.
Klein collaborated with the Parisian manufacturer
and retailer of artist's materials, named Edward Ardane,
to develop a recipe for this binder for ultramarine.
To protect this new wonderful new paint from misuse,
that he felt might compromise the purity of his idea.
He patented this colour in 1960.
The significance of this little episode in art history
is not only to show that some artists were still
even then depending on chemical assistance in the modern era,
but also to show that the intimate relationship
for painters with their materials hasn't been entirely severed.
Today painting is an unfashionable art;
many young artists instead want to work in sculpture or installation or video
and while this itself leads to some interesting new directions in colour,
it's hard to imagine that paint has really nothing more to say about colours.
There are still painters who care deeply about colour,
but they're few and they're rarely young.
In an age where painters seem to have more choice to materials than ever before,
this might seem strange.
But I can't help wondering whether in a way
that surplus of choice might contain the very problem,
that artists have lost confidence in paint
because they no longer feel they understand it.
I can't help but feel sad at how different this is
from the spirit that is apparent in an account
by the photographer Brassai of a conversation that he had with Picasso.
This is what Brassai said:
"Then the man in the blue suit (this is Picasso)
reaches into his pocket and takes out a large sheet of paper
which he carefully unfolds and hands to me.
"It is covered with Picasso's handwriting;
less spasmodic, more studied than usual.
"At first sight it resembles a poem,
20 or so verses are assembled in a column surrounded by broad white margins.
"Each verse is prolonged with a dash, occasionally a very long one.
"But it is not a poem,
it is Picasso's most recent order for colours.
"For once, all the anonymous heroes of Picasso's palette
trooped forth from the shadows with permanent white at their head.
"Each had distinguished himself in some great battle:
the blue period; the rose period; cubism, guernica.
"Each could say, 'I too, I was there'.
Picasso reviewing his old comrades in arms,
gives to each of them a sweep of his pen,
a long dash that seems a fraternal salute.
"Welcome, Persian red. Welcome, emerald green,
cerulean blue, ivory black, cobalt violet clear and deep. Welcome, welcome."
Thank you very much.
Thank you very much. (Applause)