Gamblin 1980 Oils - PB27:1 Prussian Blue
Gamblin’s approach is different. 1980 colours contain pure
pigments, the finest refined linseed oil, and marble dust (calcium carbonate).
Since oil painting began, these three ingredients have made more affordable
colours.
Painters experience true colours without homogenized texture
or muddy colour mixtures. Gamblin's approach to using traditional raw materials
and processes ensures that artists experience the luscious working properties
they expect from their oil colours.
Prussian Blue: The first synthetic colour of the Industrial
Revolution was discovered by accident in 1704 while a chemist was trying to
formulate artificial crimson. It is a cool blue with a more muted tint than
Phthalo Blue. It has a high tinting strength, is lightfast, and is especially
beautiful in its transparency.
Prussian Blue is a semi-transparent, deep cyan-blue with a
greenish undertone and a very high tinting strength unequalled by most
pigments.
PIGMENT COMPOSITION AND PERMANENCE
- Pigment Name: PB27:1 Prussian Blue (Ferric-ammonium
ferrocyanide)
- Pigment Type: inorganic
PROPERTIES
Prussian Blue is a semi-transparent, deep cyan-blue with a
greenish undertone and a very high tinting strength unequalled by most
pigments. It is similar to Phthalo Blue unless mixed with white when it gives
up intensity and becomes smoky.
It can behave erratically and less reliably in oil and
watercolour form, depending on its manufacture. Phthalo Blue is considered a
more reliable choice for permanent painting.
PERMANENCE
Prussian Blue is lightfast and permanent in all techniques
except for fresco. When mixed with Zinc White in watercolour or tempera form,
it fades upon exposure to light and completely regains its chromatic strength
in the dark. Modern manufacturing techniques have made this tendency less of an
issue in recent years.
TOXICITY
Prussian Blue is moderately toxic if ingested. It will emit
toxic hydrogen cyanide gas if heated, exposed to ultraviolet radiation, or
treated with acid.
HISTORY
The first of the modern pigments: Prussian Blue is the first
artificial pigment with a known history. It was discovered by accident in 1704
by the Berlin colour maker Heinrich Diesbach, who tried to create a pigment
with a red hue by mixing iron sulphate and potash.
The potash Diesbach purchased from a local laboratory had
been contaminated by animal oil and blood during previous experimentation. The
resulting mixture yielded a very pale red that changed to purple and deep blue
when he tried to concentrate it.
Since previous blue pigments came from lapis lazuli, an
expensive stone, Diesbach’s discovery was significant for artists of the time.
