Great American Handmade Pastel - Corfu 0, 180.0

Pigment Information

This color contains the following pigments:

PY35-Cadmium Yellow

PBr7-Raw Sienna

PW18-Calcium Carbonate

PG7-Phthalo Green

Pigment Name

PY35-Cadmium Yellow

Pigment Type

inorganic, cadmium

Chemical Name

cadmium zinc sulfide

Chemical Formula

CdZnS

Properties

Cadmium Yellow is brilliant, dense, and opaque, with good tinting strength and very high hiding power. It is the artist's principal bright yellow and is available in light, medium, and dark shades. The deeper shades appear deep orange and have the greatest tinting strength. It is slow-drying in oil form and is used in both oil and watercolor form. It cannot be mixed with copper-based pigments. A clean Cadmium Orange is created when Cadmium Yellow is mixed with Cadmium Red. Hues vary by brand. Cadmium pigments have been partially replaced by azo pigments, which are similar in lightfastness to the cadmium colors, cheaper, and non-toxic. Cadmium Yellow is usually available in a pure grade, or in a cadmium-barium mix. This mix has the same permanence with a lower tinting strength.

Permanence

Cadmium Yellow is lightfast and permanent in most forms, but like most cadmium colors, it will fade in fresco or mural painting. The deeper shades are the most permanent. The pale varieties have been known to fade with exposure to sunlight in conditions where moisture is able to penetrate the binder.

Toxicity

Cadmium Yellow is a known human carcinogen. It can be hazardous if chronically inhaled or ingested.

History

Cadmiums get their names from the Latin word cadmia meaning zinc ore calamine, and the Greek word kadmeia, meaning Cadmean earth, first found near Thebes, the city founded by the Phoenician prince Cadmus. Metallic cadmium was discovered in 1817 by Friedrich Strohmeyer. Oil colors were first made from Cadmium Yellow pigments in 1819, replacing toxic Chrome (lead) Yellows. However, their production was delayed until 1840 due to the scarcity of cadmium metals. Landscape painters, such as Claude Monet, preferred Cadmium Yellow to the less expensive Chrome Yellow because of its higher chroma and greater purity of color.

Pigment Name

PBr7-Raw Sienna

Pigment Type

earth

Chemical Name

hydrated iron oxide

Chemical Formula

α-FeO3+(OH) or Fe2O3

Properties

Raw Sienna is a moderately dull deep earth yellow with medium tinting strength and excellent transparency. It is one of the basic permanent artists' pigments and is made from a form of limonite clay whose yellow-brown color results from ferric oxides. Raw Sienna is preferable to Yellow Ochre for creating flesh tones, due to its higher subtlety of color when mixed with white. It creates a bright Ochre when mixed with Cadmium Yellow and creates greens and grays when mixed with Ultramarine. Raw Sienna dries quickly.

Permanence

Raw Sienna has good permanence.

Toxicity

Raw Sienna has no significant hazards.

History

Raw Sienna has been used as a pigment since prehistoric times, although 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.

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.