Color Swatch created using heavy application/diluted application and was applied on cold press watercolor paper (150 lb) material.
This color contains the following pigments:
PG17—Chromium Oxide Green
Pigment Type
inorganic
Chemical Name
chromium oxide
Chemical Formula
Cr2O3
Properties
Chromium Oxide Green is a dull, dense, willow or pale green color that is completely opaque. It has an average drying time and a low tinting strength. It is fairly flexible in oil form and is suitable for all purposes and mediums. This pigment is less versatile in mixtures than Viridian and Phthalocyanine Green, but mixes well with other colors without overpowering them.
Permanence
Chromium Oxide Green has excellent permanence, even at high temperatures.
Toxicity
Chromium Oxide Green is slightly toxic. Evidence of Chromium(III) carcinogenicity is inconclusive. Chromium(III) salts appear in greenish pigments such as PG17. Chromium(VI) salts, which appear in yellowish pigments, have been proven to cause cancer.
History
Louis-Nicolas Vauquelin discovered the element chromium in lead chromate in 1797. It began to be used as an enamel and ceramic color in 1809, but it had limited use as a pigment until 1862, because of its cost. It is the most commonly used green for military camouflage because it appears the same shade as living foliage under infrared light.
Alternate Names
Chrome Oxide Green, Olive Green, Permanent Green. Varieties of Chromium Oxide Green include Arnaudon's Green, Dingler's Green, Plessy's Green, and Schnitzer's Green.
PY1—Hansa Yellow G
Pigment Type
organic, monoazo
Chemical Name
n/a
Chemical Formula
C17H16N4O4
Properties
This Hansa yellow is a transparent yellow. It has great brightness and tinting strength and its drying time ranges from average to slow.
Hansa Yellow makes more intense tints and cleaner secondaries than Cadmium Yellows, especially when mixed with other organic or modern colors like Phthalo Blue and Green. Because they are more transparent, they have great value as glazing colors.
Permanence
Hansa Yellow G has good permanence and lightfastness, particularly in the lighter shades.
Toxicity
Hansa Yellow pigments have no significant acute hazards, though chronic hazards have not been well studied.
History
Hansa Yellows were first made in Germany just before World War I from a series of synthetic dyestuffs called Pigment Yellow. Hansa Yellow G, introduced in 1910, was the first of these products to be commercialized. Hansa Yellow G was the standard yellow for printing inks until late in the 20th century, when stronger diarylide yellows began to replace it. It is still used a great deal in packaging, and for air drying paints.
Alternate Names
Light Fast Yellow G, Pigment Yellow G, Arylide, Arylide Yellow, Azo Yellow, Brilliant Yellow, Monoazo Yellow, Monolite Yellow, Permanent Yellow.
PBk7—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 or tinting power. It is typically the most opaque black in watercolor form. Though a very pure black, it tends to muddy slightly in mixtures. Natural sources may be brownish or bluish in tone because of impurities. When used in oil paints, it is one of the slowest drying pigments, and should not be used in underpainting or applied in layers underneath other colors.
Permanence
Lamp Black is very lightfast and absolutely permanent. It is used in all techniques in permanent painting.
Toxicity
Carbon itself is not considered hazardous, however other combustion products that are hazardous are often present as impurities when Lamp Black is produced from natural materials. For this reason, commercial preparations of the pigment should be considered slightly toxic. Avoid skin contact and inhalation. Where such impurities are present, Lamp Black 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 has been used as a pigment since prehistoric times. It is the black found in Egyptian murals and tomb decorations and was the most popular black for fresco painting until the development of Mars Black.
Alternate Names
Carbon Black, Channel Black, Furnace Black, Oil Black, Vegetable Black. Flame Black is an impure version of Lamp Black. An alternate spelling is Lampblack, in which the first syllable is stressed and the two words are elided to form a closed compound.
