Great American Handmade Pastel - Vermont 6, 280.6

Pigment Information

This color contains the following pigments:

PW18-Calcium Carbonate

PG7-Phthalo Green

PG26-Cobalt Green Deep

PBk6-Lamp Black

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

PG7-Phthalo Green

Pigment Type

organic

Chemical Name

polychlorinated copper(II) phthalocyanine

Chemical Formula

C32H3Cl13CuN8 to C32HCl15CuN8 or C32H16CuN8Cl15 (PG7) or C32Br6Cl10CuN8 (PG36)

Properties

Phthalo Green is a transparent, cool, bright, high intensity color used in oil and acrylics. It comes from a Phthalocyanine Blue pigment where most of the hydrogen atoms have been replaced with chlorine, forming highly stable molecules.  It has similar pigment properties and permanence to Phthalo Blue. It is slow drying and an excellent base color for mixing a range of bright greens. Phthalo Green is considered a very good alternative to Viridian because it is intense and mixes well and can be used to emphasize mineral colors in various tints. However, its tinting strength is very high, so it can overpower other colors.  This pigment most closely resembles the discontinued and toxic Verdigris.

Permanence

Phthalo Greens are completely lightfast and resistant to alkali, acids, solvents, heat, and ultraviolet radiation. 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.

Toxicity

Phthalo Green has no significant hazards, but it contained PCBs (polychlorinated biphenyls) until 1982.

History

This bright blue-green was developed in 1935 and has been in use since 1938.

Pigment Name

PG26-Cobalt Green Deep

Pigment Type

inorganic

Chemical Name

Cobalt chromium oxide

Chemical Formula

Properties

This pigment offers a deep but dull and opaque tone of Cobalt Green. It has moderate covering power, but low tinting strength. It is primarily for use on its own, or for mixing with other cobalt colors. It is an alternative to cobalt(II) zinc oxide, another form of Cobalt Green.

Permanence

Cobalt pigments are absolutely lightfast.

Toxicity

Cobalt chromium oxide is slightly toxic, and is a possible carcinogen.

History

Cobalt chromium oxide is an alternative Cobalt Green to the better known cobalt zinc oxide. Both pigments were used by landscape artists before phthalocyanine-based pigments became widely available in the 20th century.

Pigment Name

PBk6-Lamp Black

Pigment Type

inorganic

Chemical Name

carbon

Chemical Formula

C

Properties

Lamp black is a very opaque, heavily staining black pigment that does not have much covering power. It is typically the most opaque black in watercolor form. Though a very pure black, it tends to muddy slightly in mixtures, is one of the slowest drying pigments in oils, and should not be used under other colors.

Permanence

Lamp Black is very lightfast and absolutely permanent. It is used in all techniques in permanent painting.

Toxicity

Lamp Black is slightly toxic by skin contact and inhalation. It is a possible human carcinogen.

History

Lamp Black is a carbon based black traditionally produced by collecting soot (known as lampblack) from oil lamps. It is the black found in Egyptian murals and tomb decorations and was the most popular black for frescoing until the development of Mars Black.