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Subject: Grammar of Color

Grammar of Color

From: Michael Skalka <m-skalka>
Date: Friday, August 31, 2007
The Grammar of Color
Vol. 3 No. 5
Go Big Blue!
Ecole Polytechnique vs. The University of Tubingen.

Scholastic rivalries have interesting histories. Each year both
school athletic teems meet to beat the tar out of each other in an
annual football game. This sporting event is preceded by a student
from one school stealing something of historic or sentimental value
from another. These cyclical crimes of larceny can be fairly benign
to exceedingly complex. Most go very badly when live animals are
involved.

In reality, this story is not really a rivalry between a French and
German university, but is was a very real competition with two
scientists who came from universities that provided them with the
knowledge, tools and the environment, to vie for an honor that would
have significant consequence for the art world.

The challenge in the early 19th century was to create an artificial
way of synthesizing ultramarine blue. Genuine ultramarine blue
apparently has never been abundant. Artists throughout history have
always used natural ultramarine sparingly. Blue colorants like
azurite were used as an under paint to provide a blue background
onto which true ultramarine would be applied. Since scarcity and
price are related, it is easy to understand that this pigment would
be zealously guarded and used judiciously. Its presence in a picture
denoted wealth. The color was equated with the robes of the Virgin
Mary and it was fitting that the expense be associated with this
figure of religious devotion. It is no wonder that we see so few
green pigment mixtures since it would have considered it wasteful to
make a mixture of genuine ultramarine and a yellow colorant.

In the 19th century, the cost of ultramarine was ever increasing and
shortages of the nearest acceptable substitute, azurite, fueled the
need to find an artificial means of producing ultramarine pigment.
The modern age of industrial processing played an important role in
the effort to bring artificial ultramarine into being. Keen
observers of manufacturing noted that the production of soda (Na2 O)
in a glass factory resulted in materials that contained a blue
colored byproduct. As early as 1814 the noted chemist, Louis Nicolas
Vauquelin identified the material from the soda kilns as being
chemically similar to natural ultramarine. Had Vauquelin been eager
to pursue a means of creating a viable process to manufacturing this
synthetic ultramarine, he could have added this pigment to the
chrome colors he helped devise several years earlier. This
observation inspired the Societe pour l'Encouragement d'industrie to
offer a prize of 6,000 francs ($1,250 in today's exchange rate) for
anyone who could duplicate the rich hue of ultramarine without the
high cost. Surprisingly, it only took 4 years for the prize to be
claimed.

It appears that two men were up to facing the challenge.
Jean-Baptiste Guimet studied chemistry at the Ecole Polytechnique in
Paris. He was no stranger to the world of pigments. Before and after
his arrival at the Ecole Polytechnique some of the best minds in
chemistry and pigment development taught there. Vauquelin was an
instructor at the university only a few years before Guimet entered
Ecole Polytechnique in 1813. Vauquelin prized student, Louis Jaques
Thenard who would later go on to produce cobalt blue, taught at the
Ecole Polytechnique. No evidence indicates that Guimet was a student
of Thenard, but they were both present at the school in the early
19th century. It might not be a coincidence that two major blue
pigments were born from the same distinguished institution. After
his education, Guimet entered Administration des Poudres et
Salpetres in 1817. Eleven year later in 1828 he captured the process
of making ultramarine using kaolin clay, feldspar, anhydrous sodium
carbonate, sulfur and coal as reducing agent.

Christian Gottlob Gmelin who lived from 1792 to 1860 was a German
chemist and professor of chemistry and pharmacy at the University of
Tubingen. Apparently, little is know about him. Gmelin was just a
month short of Guimet in publishing the method he used to obtain
artificial ultramarine. This brief lag allowed Guimet to claim the
prize. All was not lost for Professor Gmelin. His process for
creating ultramarine was slightly different than the one devised by
Guimet. It was employed in a number of factories in Germany and
while not directly indicated, must have provided some sort of
financial reward to Gmelin.

It is important to note that the prize stipulated that it would be
awarded to the person who invented a cost effective method of making
a synthetic ultramarine. While artificial ultramarine mimics the
chemical structure of genuine lapis lazuli, it was not stipulated
that it had to mirror the structure of the original pigment. It just
had to perform and appear in color to match genuine ultramarine and
be inexpensive enough to produce on a large scale. Inexpensive,
small batch production would not meet the criteria. Success was
predicated on cheap mass production. Guimet managed to create
artificial ultramarine for about 880 francs per kilo. Genuine lapis
pigment sold at the time for 6,000 to 9,000 francs per kilo.
Recalling the prize amount awarded to Guimet at first glance seems
significant, but it would only have purchased a single kilo of
natural lapis lazuli in the early 19th century.

The ultimate dividend was the knowledge of production, not the prize
that was awarded. Guimet went on to open up a factory in Fleurieux
sur Saone. The factory was very successful and management of the
facility was passed on to Guimet's son Emile.

No indication that a Ecole Polytechnique and University of Tubingen
interschool rivalry exists. Students don't paint their bodies blue
and shower the opposing university with clods of ultramarine pigment
during some collegiate sporting event. Starting trouble between
these two seats of higher learning after a 178-year hiatus might be
ridiculous. However, it has great visual potential as the two
schools employ ultramarine blue in a variety of exciting ways to
ignite a battle for dominance between two institutions.

If others you know want to receive The Grammar of Color and our
lecture announcements, send me a message at m-skalka [at] nga__gov
requesting to be on the recipient list.


                                  ***
                  Conservation DistList Instance 21:22
                Distributed: Monday, September 10, 2007
                       Message Id: cdl-21-22-017
                                  ***
Received on Friday, 31 August, 2007

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