Painting with Broken Glass

a Reconstruction

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Since prehistory man has attempted to reproduce the deep blue colour of a clear summer sky. The heavenly blue that is thought to house and represent the unpredictable, divine powers.
Blue is a rare colour in our earth’s colour-scheme which is dominated by floral greens and the many hues of ochres. Easy to find ochres used in colouring the earliest art, supplemented with the whites of lime and charcoal blacks.

Blue and green pigments and paints, and the words used to name them, appeared much later.
As usable pigments and stable colours they were hard to come by, they were either hidden in ore, like cobalt and copper, or embedded in enclosing rock, like lapis lazuli.
Azurite is the oldest source for blue pigment, first used in the ancient cultures of the Middle East. It is a member of the copper-family, hence it’s blue is tinted with a green hue, making it less suitable to imitate the warm blue of the heavens.

For about 6000 years the only  genuine alternative was the pigment made from the deep blue variety of lapis lazuli. However, it’s scarcity meant that for most people it was unavailable or unobtainable. For the whole of Eurasia and Africa the only known sources were from the remote mines of the hostile Kokchan-valley in Badakshan, modern Afghanistan.
A very welcome alternative became available around 5000 years ago as a product of the expanding Middle-Eastern glass-industries. Red, green, yellow and blue glass grew to be the man-made alternative for colourful but rare gemstones, easily manipulated in moulds of various sizes.
The blue variety of glass, the imitation lapis, was made by adding cobalt to the basic glass-ingredients.

The famous funeral mask of Tutankhamen is a beautiful example of the use of  blue cobalt glass and enamel in combination with genuine lapis lazuli.

Christianity established as the main religion on the European continent during the Middle Ages. With it’s increasing power, the need for representative and dominating symbols grew, culminating in the extraordinary piece of architecture: the cathedral.

the intense blue of the Saint Denis Cathedral stained-glass Rose window

The abbot of Saint Denis, Suger (ca. 1081-1151) is considered to be the initiator of the first grand stained-glass windows. They were commissioned for the far-reaching expansion of the monastery’s church, turning it into the first known cathedral. For his church, Suger wanted the windows to represent ‘.. the inaccessible light where God lives’. Light which could only be of the most intense, enveloping blue.
And thus were they created.

Cobalt, the raw material used in colouring blue glass was a by-product from the mining of silver and other ores. It was used to produce the so called saffer, after sapphire. Not the gemstone we know under that name, but the lazuli-stone, then considered far more precious than gold and sapphire. Somewhere  the idea was had by someone to turn Saffer into smalt by grinding the  blue lumps of molten glass into a pigment. A pigment resembling lapis, but readily available and far less costly.

a piece of smalt/saffer, as sold by Kremer Pigmente

 Painters and decorators welcomed the solution which put an end to the constant scarcity of genuine ultramarine and the unsatisfying hues of azurite. Despite it’s caprices smalt became one of the regular pigments. However,  to maintain it’s colour it had to be used rather coarsely: the finer the grain, the paler the colour.

Coarsely ground smalt, so called strooiblauw. Collection of author

Smalt, as a warm blue, raised considerably the colour-temperature of the painter’s palette. Beautiful examples are the skies in Dutch landscape paintings, as in the ‘River-scene’ by Jan van Goyen (1596-1656).

http://www.nationalgallery.org.uk/paintings/jan-van-goyen-a-river-scene-with-a-hut-on-an-island

Kobold (hence ‘cobalt’) the little blue ghost, believed by the miners to inhabit the ore, continued to play it’s games. Painters knew of the problems ill treated smalt could give; I wonder whether they could really imagine the enormous impact of discoloured smalt on their work. 
Old smalt-blue can still be enjoyed today, as seen in Van Goyen’s painting, but it can also have lost it’s colour completely. Changed into a dull brown, deforming the composition and, importantly, changing the meaning of a painting. Actually diminishing all of the painter’s hard work.

http://www.nationalgallery.org.uk/paintings/jan-jansz-treck-still-life-with-a-pewter-flagon-and-two-ming-bowls

The above still-life by Jan Jansz. Treck (1605-1652) is, unfortunately, a fine example. It seems an old  painting displaying the golden-brown glow of age. However, we may ask ourselves does this kind of greenish china-ware exist? Does it make sense?
What we are in fact looking at is a coat of yellowed varnish in combination with a vanished blue. Linseed-oil and smalt don’t really like each other. The colour of the tiny glass-particles is eventually swallowed by the oil when not applied properly, or when the smalt is not of the right quality. What Treck originally painted was a fine blue tablecloth with a blueish background, and on the table a still-life of the most exquisite blue-white china and an expensive crystal glass. Symbols of wealth as the Dutch liked to display.

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Van Gogh Blues


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Imagine….a world without blue pigments. Not just blue paints but also dyes, the colourants for textiles and leather, inks and plastics. Leaving the sky above our heads as the only large blue surface in sight, in summer accompanied by the short-lived flowers of fields and mountains.
For thousands of years this was the actual situation.
Strong, warm and bright blue pigments were rare, with lapis lazuli as the ultimate, most revered and exclusive exception.
A painting like Van Gogh’s Dr Gachet from 1890, with its abundant use of blue and red, would have been a phenomenon. Displaying colours and pigments normally reserved for the religious and worldly elite.

The 19th century was an exceptional age having an unprecedented effect on the use and possibilities of colour and paint with France, and in particular Paris, as the driving forces.
Napoleon’s hunger for territory and power resulted in almost endless processions from every corner of the new Empire to it’s capital, Paris, transporting artworks to what later would become the Musée du Louvre.

Napoleon is considering an Egyptian mummy for his collections, ca. 1800.

This art-flood had it’s consequences. Many art-works were damaged during the often long transports and needed restoration before being displayed. To this purpose the French government installed in 1794 a Conservatoire du Muséum des Arts. The demand for historic and rare blue pigments, like lapis lazuli and azurite, gave birth to the development of new pigments that changed the painters palette and finally brought an end to the scarcity of bright blue paints.

Cobalt-blue was developed by Thénard around 1802, followed by ultramarine, the long sought for replacement of lapis lazuli, in 1828 by Guimet.

Cobalt-blue was and still is relatively expensive (cheap cobalt is not the real thing!), but ultramarine turned out to be a rather economic pigment. The cheapest varieties were used as whiteners for laundry, of which Reckitt’s Blue is one of the best known. The latter is an ideal substitute for painters lacking resources to buy proper pigments, like the young Van Gogh, who even used coffee grounds to make his brown paints. 

Van Gogh ‘The poor and the money’, 1882, mixed media on paper

Van Gogh considered cobalt-blue to be une couleur divine, a divine colour, ideal for suggesting space in the restricted two-dimensions of a canvas. The portrait of Dr. Gachet is a beautiful example of his love for an abundant use of cobalt, indirectly made possible thanks to the expeditions of Napoleon.

Le Docteur Paul Gachet, 1890, 68 x 57 cm, Musée d’Orsay, Paris
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