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:
PG18—Viridian
Pigment Type
inorganic
Chemical Name
chromium(III)-oxide dehydrate
Chemical Formula
Cr2O3 • 2 H2O or Cr2(OH3)
Properties
Viridian is the standard green and is stable, powerful, and cold with an emerald green undertone. It has a transparent hue, good tinting strength, a dark masstone that can be almost black at full strength, and a slow drying time in oil form. Viridian is commonly replaced by the darker, more saturated, and staining Phthalo Greens, but its properties make it a necessary part of the palette of an experienced landscape painter.
Permanence
Viridian has excellent permanence, except in high-temperature work, and is highly valued as a glazing color.
Toxicity
Viridian is slightly toxic.
History
Viridian’s name comes from the Latin viridis, meaning green. The process for manufacturing Viridian, or Transparent Oxide of Chromium, was patented by Guignet in Paris in 1859. However, it had actually been discovered by Pannetier and Binet in 1838. Viridian replaced Verdigris, which was reactive and unstable, and Emerald Green, which was a poisonous copper aceto-arsenite used as a rat poison in the sewers of Paris.
Alternate Names
Emerald Chromium Oxide, Emeraude Green, French Veronese Green, Guignet’s Green, Pannetier's Green, Permanent Green, Smaragd Green, Transparent Oxide of Chromium, Vert Emeraude. Casali's Green and Mittler's Green are varieties of Viridian. Viridian has historically been sold under the name Emerald Green, but they are currently considered to be and are marketed as two different pigments.
PG36—Phthalo Green
Pigment Type
organic
Chemical Name
polybromopolychlorinated 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. Pigment PG36 differs from PG7 in that a portion of the chlorine atoms are replaced with bromine atoms, which are reactively similar, but cause a yellow shift that is especially noticeable in mixtures. Phthalo Green 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.
Alternate Names
Bocour Green, Cyan Green, Intense Green, Monastral Green, Phthalocyanine Green, Rembrandt Green, Thalo Green, Winsor Green.
PG50—Cobalt Green
Pigment Type
inorganic
Chemical Name
cobalt titanium oxide
Chemical Formula
Co2TiO4
Properties
Cobalt Titanium Oxide is a low intensity color with a weak tinting strength, similar to Cobalt Blue. It has an average to fast drying time.
Permanence
Cobalt Green has excellent permanence and lightfastness.
Toxicity
Cobalt Green is considered toxic due to its cobalt component. Do not breathe its dust.
History
Since ancient times, smalt blue has been used to color glass and ceramics. Cobalt salts, which give smalt its characteristic blue color, were identified in the 18th century. Techniques for manufacturing various cobalt salts, offering a range of blues and greens, were developed in the 19th century.
Alternate Names
Cobalt Teal, Cobalt Turquoise, Light Green Oxide
PW6—Titanium White
Pigment Type
inorganic
Chemical Name
titanium dioxide
Chemical Formula
TiO2
Properties
Titanium White is the most brilliant of the white pigments. It is considered an all purpose oil color useful in all techniques and the best all around white. Its masstone is neither warm nor cool, placing it somewhere between Lead White and Zinc White. It is less prone to cracking and yellowing than Lead White, but it still yellows easily. Titanium White dries slowly in oil form, more slowly than Lead White but more quickly than Zinc White. It is opaque in oil and acrylic forms and semi-opaque in watercolor form. This pigment has good chemical stability, and its tinting strength is superior to both Lead White and Zinc White.
Permanence
Titanium White has excellent permanence and lightfastness.
Toxicity
Titanium dioxide is highly stable and is regarded as completely non-toxic. Animal studies give no indiciation that it is absorbed biologically, even after long periods of exposure. The primary safety concern is with inhalation of fine pigment dust particles. Titanium White, if inhaled in large amounts over the course of several years, may cause a benign pneumoconiosis that is visible on x-rays. The National Institute of Occupational Safety and Health (NIOSH) considers fine titanium dioxide particles, if inhaled, to be a human carcinogen. The primary concern for artists is to avoid exposure to fine particulate dust from raw pigments.
History
Titanium is the ninth most abundant element in the Earth's crust, however mineral deposits that are economical to mine are less common. Titanium dioxide was first discovered in 1821, although it could not be mass produced until 1919. Widespread use of the pigment began in the 1940s. Since that time, it has become the most commonly used white pigment. The name comes from the Latin word Titan, the name for the elder brother of Kronos and ancestor of the Titans, and from the Greek word tito, meaning day or sun.
Alternate Names
None.
