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:
PB27—Prussian Blue
Pigment Type
inorganic
Chemical Name
ferric ferrocyanide/iron(III)-hexacyanoferrate(II)
Chemical Formula
Fe7(CN)18(H2O)x or C6FeN6H4N
Properties
Prussian Blue is a semi-transparent, deep cyan-blue with a greenish undertone and a very high tinting strength unequaled by most pigments. It is similar to Phthalo Blue unless mixed with white, when it gives up intensity and becomes smoky. It can behave erratically and less reliably in oil and watercolor form depending on its manufacture. For permanent painting Phthalo Blue is considered a more reliable choice.
Permanence
Prussian Blue is lightfast and permanent in all techniques except for fresco. When mixed with Zinc White in watercolor or tempera form, it fades upon exposure to light and completely regains its chromatic strength in the dark. Modern manufacturing techniques have made this tendency less of an issue in recent years
Toxicity
Prussian Blue is moderately toxic if ingested. It will emit toxic hydrogen cyanide gas if heated, exposed to ultraviolet radiation, or treated with acid.
History
"The first of the modern pigments," Prussian Blue is the first artificial pigment with a known history. It was discovered by accident in 1704 by the Berlin color maker Heinrich Diesbach, who was trying to create a pigment with a red hue by mixing iron sulfate and potash. The potash Diesbach purchased from a local laboratory had been contaminated by animal oil and blood during previous experimentation. The resulting mixture yielded a very pale red that changed to purple and then deep blue when he tried to concentrate it. Since previous blue pigments came from lapis lazuli, an expensive stone, Diesbach’s discovery was extremely important for artists of the time.
Alternate Names
Berlin Blue, Bronze Blue, Iron Blue, Paris Blue, Paste Blue. Celestial Blue, Monthier Blue and Soluble Blue are varieties of Prussian Blue. Blue Lake is a reduced or let-down variety of Prussian Blue. Chinese Blue, Milori Blue, and Steel Blue are the three highest grades of Prussian Blue.
PBk9—Ivory Black
Pigment Type
charred animal bone
Chemical Name
carbon + calcium phosphate
Chemical Formula
C + Ca3(PO4)2 or C × CaPO4
Properties
Ivory Black is a cool, semi-transparent blue-black with a slight brownish undertone and average tinting strength. It mixes well with any color, and creates a range of dull greens when mixed with yellow. It has good properties for use in oil, can be slow to dry in oil form, and should never be used in underpainting or frescoing. Ivory Black is denser than Lamp Black.
Permanence
Ivory Black is very lightfast and has good permanence, though it is considered the least permanent of the major black pigments.
Toxicity
Ivory Black has no significant hazards.
History
Ivory Black is a carbon based black first named as Elephantium, and described in the 4th century BCE as produced by heating ivory scraps in clay pots to reduce the ivory or bone to charcoal. The deviation in names is because the more expensive varieties of this pigment were made by burning ivory, and the less expensive ones by burning animal bone. In the 19th century, the name Ivory Black was finally permitted to be applied to Carbon Black pigments made from bone. True Ivory Black is rare in modern times due to the protection of ivory, and the synthetic variety produced today was discovered in 1929. Bone Black is produced as an industrial pigment.
Alternate Names
Animal Black, Blue Black, Bone Black. Paris Black is an inferior grade of Ivory Black. Incorrectly labeled as Frankfort Black.
