Gamblin Artist's Oil Color - Indigo, 37 ml tube

Pigment Information

This color contains the following pigments:

PB15:2-Phthalo Blue

PV15-Ultramarine Violet

PBr7-Burnt Sienna

Pigment Name

PB15:2-Phthalo Blue

Pigment Type

organic

Chemical Name

copper phthalocyanine

Chemical Formula

C32H16CuN8

Properties

Phthalo Blue PB15:2 is a structural variant of Phthalo Blue PB15 that produces more greenish tones.

Permanence

Phthalo Blues are completely lightfast and stable and are permanent for all paint uses. They are currently used in inks, coatings, and many plastics due to their stability and are considered a standard pigment in printing ink and the packaging industry.

History

Developed by chemists using the trade name Monastral Blue, the organic blue dyestuff now known as Phthalo Blue was presented as a pigment in November 1935 in London. Its discovery was accidental. The dark color was observed in a kettle where a dye was being made from a British dyestuff plant. The demand for such a pigment came from commercial printers who wanted a cyan to replace Prussian Blue.

Pigment Name

PV15-Ultramarine Violet

Pigment Type

inorganic

Chemical Name

complex silicate of sodium and aluminum with sulfur

Chemical Formula

H2Na(4-6)Al6Si6O24S2

Properties

Ultramarine Violet is a semi-transparent, dull purple to pale violet with low tinting strength. As a pigment, it is weak in most oil applications, but it performs better in water-based mediums, pastels, and chalks. It is generally the bluest of the violet pigments, although there can be significant differences in color across brands. It is not suitable for fresco work and does not mix well with yellows. Ultramarine Violet is a variant of Ultramarine Blue, and their pigment properties are identical.

Permanence

Ultramarine Violet has excellent permanence and lightfastness.

History

Unknown.

Pigment Name

PBr7-Burnt Sienna

Pigment Type

earth

Chemical Name

iron oxides

Chemical Formula

Fe2O3

Properties

Burnt Sienna is a warm, mid-brown color formed by burning the yellow-brown limonite clay called Raw Sienna. It ranges from semi-opaque to semi-transparent due to the combination of its opaque, red-brown mass tone and its transparent, orangey undertone. It is an excellent mixing complement for blues and greens and creates salmon or peach colored tints when mixed with white. It can be useful for subduing bright colors and does not get chalky in dark mixtures.

Permanence

Burnt Sienna has good permanence and is considered one of the most versatile of the permanent pigments.

History

Burnt Sienna has been used as a pigment since prehistoric times, but its current name came about during the Renaissance. It comes from the city of Siena, in Italy, and is short for terra di Siena, meaning earth of Siena. Sienna was famous for the mining and production of earth pigments from the Renaissance until World War II. Due to the depletion of clay deposits in Tuscany, Italian siennas now come from other areas, including Sicily and Sardinia.