Great American Handmade Pastel - Maple 3, 155.3

Pigment Information

This color contains the following pigments:

PBr33-Zinc Iron Chromite Brown

PW18-Calcium Carbonate

PBr7-Raw Umber

Pigment Name

PBr33-Zinc Iron Chromite Brown

Pigment Type

inorganic

Chemical Name

zinc-iron-chromite spinel

Chemical Formula

ZnO + Fe203 + Cr2O3

Properties

Zinc Iron Chromite Brown is a dark reddish brown pigment that is opaque and staining.

Permanence

Zinc Iron Chromite Brown is exceptionally lightfast, heat resistant, weather resistant, and durable.

Toxicity

Zinc Iron Chromite Brown has not been identified as hazardous, but it is likely to contain impurities that are irritating to the skin or lungs. Pigment from natural ores may contain traces of heavy metals.

History

Because of its exceptional durability and heat resistance, Zinc Iron Chromite is used as a brown pigment in ceramics.

Pigment Name

PW18-Calcium Carbonate

Pigment Type

inorganic

Chemical Name

calcium carbonate

Chemical Formula

CaCO3

Properties

Calcium carbonate, the mineral constituent of chalk, is a low tinting strength, inexpensive white pigment that is often used is a buffer and filler. Because of its low tinting strength, it is overwhelmed by other colors. It is used in gesso and other coatings to give the surface more tooth, a desirable characteristic for some painting techniques.

Permanence

Calcium carbonate is lightfast. Like all carbonates, it reacts with strong acids

Toxicity

Calcium carbonate is completely non-toxic, and is used in many food, cosmetic, and pharmaceutical products. However, excessive consumption is not recommended. 

History

Naturally occuring chalk deposits have been mined since prehistoric times. Rocks and minerals that contain calcium carbonate include aragonite, calcite, vaterite, chalk, limestone. marble, and travertine. Calcium carbonate is the principle component of lime, used in many agricultural and industrial applications.

Pigment Name

PBr7-Raw Umber

Pigment Type

earth

Chemical Name

hydrated iron oxide

Chemical Formula

α-FeO3+(OH) or Fe2O3 × MnO2

Properties

Raw Umber is a cool, transparent brown ranging from yellowish brown to greenish brown. It has surprisingly good tinting strength, a high level of opacity, mixes well with greens, and is quick drying in oil form. It has excellent color properties and can create a variety of subtle, clear tints when mixed with white. It grays when mixed with blue and white. Raw Umber can tend towards chalkiness in dark mixes in oil form.

Permanence

Raw Umber has excellent permanence.

Toxicity

Raw Umber itself is considered non-toxic. If contaminated by manganese compounds, it may be highly toxic if inhaled and moderately toxic if ingested.

History

This pigment gets its name from the Latin word umbra, meaning shadow or shade. Its full name is listed as terra di ombra, meaning earth of shadow/shade, due to its original extraction from the area of Umbria, Italy. It has been used as a pigment since prehistoric times. Currently, the finest umber comes from Cyprus.