Color Swatch created using heavy application/medium application/50% tint and was applied on acrylic primed canvas (7 oz) material.
This color contains the following pigments:
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.
Toxicity
Burnt Sienna has no significant hazards.
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.
Alternate Names
Caput Mortuum, Italian Earth, Natural Brown Iron Oxide, Sienna, Spanish Red, Vandyke Brown.
PB27—Antwerp Blue
Pigment Type
inorganic
Chemical Name
ferric ammonium ferrocyanide
Chemical Formula
C18Fe7N18
Properties
Antwerp Blue is a slightly warm and less saturated blue with good transparency and undertone clarity. It is a pale variety of Prussian Blue with 75% inert pigment. It has similar properties to pure Prussian Blue, but its overall performance is inferior.
Permanence
Antwerp Blue can fluctuate, fading in the light and recovering in the dark. In watercolor form, it fades when mixed with white pigment or extender. Although it has reasonably good lightfastness and permanence, it is not considered ideal for permanent painting.
Toxicity
Antwerp Blue is mildly toxic by ingestion, but is considered safe for external use. In the United States, ferric ferrocyanide is permitted as a coloring ingredient for externally applied cosmetics, but not for lipsticks or internal use. If the pigment is exposed to ultraviolet radiation, heated, or treated with acid, it becomes reactive and releases toxic hydrogen gas.
There has been some confusion and controversy about whether ferric ferrocyanide and ferric ammonium ferrocyanide should be classified as a "cyanide" and as a toxic or environmental pollutant. The United States Environmental Protection Agency has issued an administrative ruling that ferric ferrocyanide is not a toxic pollutant, and that its use as an ingredient in road salt and deicing mixes is permitted.
History
Antwerp Blue was developed through experimentation with Prussian Blue.
Alternate Names
Haarlem Blue, Mansa Blue, Mineral Blue
PR57—Lithol Rubine
Pigment Type
organic, monoazo
Chemical Name
n/a
Chemical Formula
C18H12N2O6, sodium salt
Properties
Lithol Rubine is a deep transparent red dye, generally slightly bluish, that is laked as a salt with sodium or calcium to form a pigment. PR57 is the sodium salt, and has a more bluish tone. PR57:1 is the calcium salt, and is the most widely used. Lithol Rubine makes clean pinks when tinted. Sources vary greatly in hue and transparency. Lithol Rubine has high tinting strength.
Permanence
Lightfastness is considered only fair to good. Superior products are available when lightfastness is paramount. Where greater lightfastness is needed in process color printing, the more expensive pigment PR184, a Naphthol AS pigment, is often substituted for Lithol Rubine.
Toxicity
Lithol Rubine is not considered toxic. It is used in food, drugs, and cosmetics, such as lipstick. It can be used in art materials intended for children.
History
Lithol Rubine pigments (especially the calcium salt PR57:1) are widely used in inks, paints, plastics, and textiles. Lithol Rubine is widely used as magenta in process color printing.
Alternate Names
4B Toner, Pigment PR57:1 is also known as D&C Red No 7, Ruby Red, Brilliant Carmine.
