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:
PB28—Cobalt Blue
Pigment Type
inorganic
Chemical Name
cobalt(II) oxide + aluminum oxide
Chemical Formula
CoO + Al2O3
Properties
Cobalt blue is a semitransparent pigment with low to moderate tinting strength. When it dries, it appears lighter and less saturated. Pigment particles are large and grainy. Differences in how the pigment is ground and mixed lead to considerable differences in its performance among various manufacturers.
Permanence
Cobalt blue is absolutely lightfast and extraordinarily stable. The stability of cobalt salts at high temperatures make them the standard for blues used in ceramics and glassware.
Toxicity
Cobalt salts are toxic. Avoid respiratory and skin contact. Soluble cobalt may cause irritation and allergic reaction through contact with skin. It is considered a possible carcinogen.
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 Cobalt Blue, a chemically pure salt of cobalt and aluminum oxide, were developed in 1802.
Alternate Names
Smalt Blue
PW7—Zinc Sulphide White
Pigment Type
inorganic
Chemical Name
zinc sulfide
Chemical Formula
ZnS
Properties
Zinc Sulphide White is a semi-transparent yellowish white pigment. Zinc sulfide and zinc oxide (PW4) are often combined to create a more natural white color. Transparency increases as particle size decreases. When slight impurities are added, zinc sulphide has phospherescent and electroluminescent properties. It is often used to manufacture fluorescent or glow-in-the-dark paints.
Permanence
Zinc Sulphide White has excellent permanence and lightfastness.
Toxicity
Zinc Sulphide is non-toxic, but ore deposits often contain lead. Traces of lead and other impurities may be present in pigment powders. Ingestion is not recommended.
History
Zinc sulfide, when combined with slight impurites, has phospherescent properties. It is often used for "invisible ink" that glows with exposure to ultraviolet light. Zinc sulfide is used in the manufacture of fluorescent paints.
Alternate Names
Chinese White
