Sennelier Oil Pastel - Olive Brown

Pigment Information

This color contains the following pigments:

PY42-Mars Orange

PG8-Hooker’s Green

PBk8-Vine Black

PBk9-Ivory Black

Pigment Name

PY42-Mars Orange

Pigment Type

inorganic, earth

Chemical Name

iron oxide

Chemical Formula

Fe2O2 or Fe2O3 • H2O

Properties

Mars Orange is a bright, extremely light red and appears almost pinkish in contrast with darker colors. It has incredible tinting strength and opacity. The synthetic form of Mars Orange is made from iron oxides and is cleaner, brighter, and denser than its ochre-based counterparts.

Permanence

Mars Orange has excellent permanence and lightfastness.

Toxicity

Mars Orange has no significant hazards.

History

The word Mars refers to the Roman god of iron and war. Mars Orange has been manufactured as a pigment since the 17th century.

Pigment Name

PG8-Hooker’s Green

Pigment Type

mix of organic pigments

Chemical Formula

C30H18FeN3O6Na

Properties

Hooker’s Green is a bright olive-green often sold in a yellowish shade and a bluish shade. Its transparency can range from dull and dark to bright and light because lightness and chroma vary based on manufacturer. Modern varieties have a rich, dark tone that provides a great range when mixing. Hooker’s Green is particularly good for landscape painting when a larger range of foliage is required. Dioxazine Violet is the best mixing compliment in watercolor form.

Permanence

The permanence and lightfastness of Hooker’s Green varies by brand. As a composite pigment historically mixed from Prussian Blue and Gamboge, its permanence is only fair. Modern replacements for Hooker's Green tend to be mixed with components that have more permanence, such as Phthalocyanine Green, Burnt Umber, and sometimes Hansa or Cobalt Yellow.

Toxicity

Hooker’s Green can be hazardous, but the toxicity level depends on the specific pigments used by each individual manufacturer or brand.

History

This pigment was originally an unreliable mix of Prussian or Iron Blue and Gamboge. Later, it became a more reliable mix of Cadmium Yellow and Phthalo Blue or Green. It was a staple green for 19th century landscape and botanical painters. Most modern Hooker’s Green paints are yellow greens with a hue angle around 140, or a mix of Phthalo Green and Burnt Umber.

Pigment Name

PBk8-Vine Black

Pigment Type

inorganic

Chemical Name

carbon

Chemical Formula

C

Properties

Black is a semi-transparent, slightly textured blue-black pigment with excellent hiding power. It has a finer grain than other black pigments, so it spreads better in watercolor. However, it is inferior in intensity, tinting strength, and chemical purity to the major black pigments.

Permanence

Vine Black has superior permanence and lightfastness because carbon absorbs light well.

Toxicity

Vine Black has no significant hazards.

History

Vine Black is a carbon based black traditionally produced by charring desiccated grape vines, stems, and wood from willow trees. These processes have been used since antiquity, though a superior artificial variety was developed in the United States in 1864 to make a black appropriate for watercolors.

Pigment Name

PBk9-Ivory Black

Pigment Type

charred animal bone

Chemical Name

carbon + calcium phosphate

Chemical Formula

C + Ca3(PO4)2 or C x CaPO4

Properties

Ivory Black is a cool, semi-transparent blue-black with a slight brownish undertone and average tinting strength. It mixes well with any color, and creates a range of dull greens when mixed with yellow. It has good properties for use in oil, can be slow to dry in oil form, and should never be used in underpainting or frescoing. Ivory Black is denser than Lamp Black.

Permanence

Ivory Black is very lightfast and has good permanence, though it is considered the least permanent of the major black pigments.

Toxicity

Ivory Black has no significant hazards.

History

Ivory Black is a carbon based black first named as Elephantium, and described in the 4th century BCE as produced by heating ivory scraps in clay pots to reduce the ivory or bone to charcoal. The deviation in names is because the more expensive varieties of this pigment were made by burning ivory, and the less expensive ones by burning animal bone. In the 19th century, the name Ivory Black was finally permitted to be applied to Carbon Black pigments made from bone. True Ivory Black is rare in modern times due to the protection of ivory, and the synthetic variety produced today was discovered in 1929. Bone Black is produced as an industrial pigment.