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What did Van Gogh’s paintings
originally look like?
Vincent loses colour
From red to pink, from pink to white and from purple to
blue: Vincent van Gogh’s paintings change colour. In
search of the most famous Dutch artist’s colour palette.
TEXT: BERRY OVERVELDE
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Discoloration is the result of reactions
in the paint due to light exposure
A
nyone looking at a painting by Vincent van Gogh
(1853-1890) will often see
a different canvas than he
saw himself. Many of his
paintings have become severely discoloured. A
large team of researchers
– from conservators and art historians to
chemists and computer scientists – are
examining this discoloration. Together
they are trying to figure out why this has
happened and what Van Gogh’s paintings oringally looked like.
Evanescent red
The most vulnerable paints are some
reds and yellows, says Muriel Geldof. She
is a chemist affiliated with the Cultural
Heritage Agency of the Netherlands,
where one of her tasks is to microscopically analyse Van Gogh’s materials. ‘Ge-
Vincent van Gogh, seen
here in a self-portrait
from 1887-1888, saw
many of his paint colours
differently than we see
them today.
ranium lake, for example, is extremely
sensitive.’ Van Gogh often used this red
paint, but in many cases it has already
completely faded. Carmine (the pigment
of which is derived from the female cochineal scale insect) also fades. Various
‘chrome yellows’, on the other hand,
darken with time. ‘There are different
tints of chrome yellow, from lemon yellow to chrome orange,’ says Geldof. ‘The
lighter tints are especially sensitive.’ The
loss of colour and discoloration are the
result of reactions in the paint due to light
exposure. They alter the chemical composition. For example, light causes some
tints of chrome yellow chrome(VI) to react to chrome(III). That produces,
among other things, chrome(III) oxide,
which has a green colour.
Colder bedroom
How the colour deteriorates can be seen
in the painting The Bedroom (1888), in
which Van Gogh used a great deal of geranium lake. In a letter to his brother
Theo, he writes that the colour in that
painting ‘will have to do the work’ and
should suggest tranquillity. ‘The floor
has red tiles,’ he noted, while ‘the walls
are a pale violet,’ and ‘the doors are lilac.’
The floor is no longer warm pink or almost red but a much colder purplish
pink. And the walls and doors are blue.
Field with Irises near Arles (1888), see
pages 38 and 39, is also discoloured, the
researchers recently discovered. The
pink flowers in the field are white now,
The top layer of paint from Field with
Irises near Arles is 2/100ths of a millimetre
thick. It no longer contains red pigment.
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A detail from Field with
Irises near Arles (1888)
under a microscope. The
original pink paint has
become white on the
surface.
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Detail from The Garden of
Saint Paul’s Hospital. Once a
colourful canvas, now faded.
Van Gogh’s paints are being
reconstructed based on
nineteenth-century recipes.
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Van Gogh’s paint is being reconstructed,
based on recipes from his time, and aged
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while the magnificent irises lean towards
blue. To obtain the best possible idea of
Van Gogh’s original colour use, the researchers digitally reconstructed a few of
his paintings – and more will follow.
Vincent’s colours
How are these reconstructions done?
The researchers collect information
The famous painting The Bedroom. On the left,
how it must have once looked, according to the
researchers, and on the right, what has become
of it after 127 years.
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about how, and how fast, colours change.
Ella Hendriks, senior conservator at the
Van Gogh Museum, collects traces of
discoloration on the canvases, for example. ‘If you’re lucky, you’ll still see traces
of the original colours under the frame,
for example. Sometimes a fresh colour
appears if you remove paint layers that
were applied during past restorations.’
The difference in colour says something
about the speed of the deterioration. The
paintings are then subjected to scans (using what’s called an X-ray fluorescence
spectrometer) and other chemical exam-
ination. When Geldof studies paint samples from Van Gogh, sometimes she can
still discern a bit of the original red under
the faded top layer – especially when Van
Gogh applied the paint thickly. How
much red still remains in the deeper layers is an indicator of how fast the paint
deteriorated.
Van Gogh’s paint is also being reconstructed, based on recipes by paint manufacturers from his time. That paint is
then artificially aged. All in all, says Hendriks, ‘we have collected many different
clues about the original colours.’ These
clues are entered into computer models,
which eventually generate digital reconstructions of the original explosion of colours.
What to do?
However, Hendriks continues: ‘We have
also managed to show what The Bedroom will look like in the future if we
don’t take action now. That was very confronting. In the end, none of the red will
remain. The floor, for example, will
change from a pinkish to a more purplish
colour in thirty years. All in all, it will be
a very different painting than the warm
bedroom the painter had in mind.’ And
this deterioration will also affect many
other Van Gogh canvases, not to mention other pieces of art from that period,
such as Pierre-Auguste Renoir’s works –
because many artists at the time used the
same paint as Van Gogh.
Is there anything we can do against the
discoloration? The research that can answer that question is still ongoing, but an
initial measure has been taken. ‘Our research has prompted us to further reduce
the light levels in the museum,’ says Hen-
driks. This will keep Van Gogh’s paintings as colourful as possible for as long as
possible.
[email protected]
MORE INFORMATION
tinyurl.com/vincentsrood: video about the
research on colour change in Vincent van
Gogh’s paintings, in which conservator Ella
Hendriks talks about her work, among other
things.
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