Color Swatch created using heavy to light application and was applied on 100 lb (163 gsm) drawing paper material.
This color contains the following pigments:
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.
Alternate Names
Chalk
PBk11—Mars Black
Pigment Type
earth
Chemical Name
iron oxides
Chemical Formula
FeO or Fe2O3
Properties
Mars Black is an opaque black with a strong and cool masstone, a slightly warm tint, and a warm brown undertone. It is not as black as Ivory Black, but it dries more quickly and has three times the tinting strength. Mars Black is normally the only black available in acrylic form and that is safe to over paint. It can be used in all media without reservation and is widely used as an alternative to Lamp Black and Ivory Black.
Permanence
Mars Black is very lightfast with excellent permanence.
Toxicity
Mars Black has no significant hazards and is the only major black pigment considered non-toxic.
History
The word Mars refers to the Roman god of iron and war. Mars Black was developed in the early 20th century from inorganic, synthetic iron oxide.
Alternate Names
Black Iron Oxide, Iron Black, Magnetic Oxide, Mapico Black, Mineral Black. Sometimes labeled as Vine Black.
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.
PBr33—Zinc Iron Chromite Brown
Pigment Type
inorganic
Chemical Name
zinc-iron-chromite spinel
Chemical Formula
ZnO + Fe203 + Cr2O3
Properties
Zinc Iron Chromite Brown is a dark reddish brown pigment that is opaque and staining.
Permanence
Zinc Iron Chromite Brown is exceptionally lightfast, heat resistant, weather resistant, and durable.
Toxicity
Zinc Iron Chromite Brown has not been identified as hazardous, but it is likely to contain impurities that are irritating to the skin or lungs. Pigment from natural ores may contain traces of heavy metals.
History
Because of its exceptional durability and heat resistance, Zinc Iron Chromite is used as a brown pigment in ceramics.
Alternate Names
Shepherd Brown 12
