A
lmost all pigments used
in artists’ paints come from big
industry and are manufactured to
have uniform, fine particle size. In
addition to the oil in which they
are ground, various additives give
them the familiar buttery-smooth
consistency artists expect.
One company based in California
resists this approach. The paints
made by Natural Pigments, owned
and operated by founding director
George O’Hanlon, are made
without any additives, so the unique
properties of each pigment in oil are
retained just as they were among
the old masters. This is one reason
their paintings look so different from
modern ones. Natural Pigments has
also started making white lead the
old way in small quantities under
carefully controlled circumstances.
One outcome is that Dutch/stack
white lead in oil is shown to be
thixotropic, a fancy word which
means that the paint will move
when being brushed, but then holds
its shape when no longer touched,
thereby allowing the artist to create
almost sculptural textured effects.
There are products artists can add to
create similar effects with modern
tube paints, but here it is simply the
pigment and the oil.
An example of this phenomenon
can be seen in still lifes by Dutch
masters of the golden age, where
the dimpled texture of citrus fruits is
mimicked by the texture of the paint
itself. This effect can be seen in the
painting by Willem Kalf illustrated
here. According to a study conducted
at the Rijksmuseum, the relief had
gotten somewhat flattened by ironing
when the picture was lined with
another canvas at some point in its
conservation history. 7
Willem Kalf (1619 – 1693)
Still Life with Silver Ewer
1655-1660
Oil on canvas
29 x 29 3/4”
Rijksmuseum, Amsterdam
Laboratory analysis of the same painting has identified three pigments, commonly used
by the old masters, that Kalf used to create the colors of his lemons and oranges: lead-tin
yellow (Pb2 SnO 4 ), orpiment (AsS), and realgar (also AsS), the latter containing arsenic. The
old masters had nothing to compare with the range of modern pigments. Saturated yellows
and opaque bright greens were in short supply. (The brilliant yellow-green in the Monet
shown here is owed to cadmium yellow.) The arsenic yellow used by Kalf, orpiment (also
known as King’s yellow) was known to be poisonous, as was the orange mineral realgar.
Over these the artist applied a yellow glaze made from an organic dye, which has faded.
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