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:
PBr7—Raw Umber
Pigment Type
earth
Chemical Name
hydrated iron oxide
Chemical Formula
α-FeO3+(OH) or Fe2O3 × MnO2
Properties
Raw Umber is a cool, transparent brown ranging from yellowish brown to greenish brown. It has surprisingly good tinting strength, a high level of opacity, mixes well with greens, and is quick drying in oil form. It has excellent color properties and can create a variety of subtle, clear tints when mixed with white. It grays when mixed with blue and white. Raw Umber can tend towards chalkiness in dark mixes in oil form.
Permanence
Raw Umber has excellent permanence.
Toxicity
Raw Umber itself is considered non-toxic. If contaminated by manganese compounds, it may be highly toxic if inhaled and moderately toxic if ingested.
History
This pigment gets its name from the Latin word umbra, meaning shadow or shade. Its full name is listed as terra di ombra, meaning earth of shadow/shade, due to its original extraction from the area of Umbria, Italy. It has been used as a pigment since prehistoric times. Currently, the finest umber comes from Cyprus.
Alternate Names
Chestnut Brown, Euchrome, Jacaranta Brown, Mars Brown, Raw Brown, Sicilian Brown. Cyprus Umber, Turkey Brown, and Turkey Umber are the best quality umbers.
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.
