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:
PB28—Cobalt Blue
Pigment Type
inorganic
Chemical Name
cobalt(II) oxide + aluminum oxide
Chemical Formula
CoO + Al2O3
Properties
Cobalt blue is a semitransparent. 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
PV19—Quinacridone Violet
Pigment Type
organic synthetic, quinacridone
Chemical Name
n/a
Chemical Formula
C20H12N2O2
Properties
Quinacridone Violet is a high performance pigment with an average drying time and uneven dispersal.
Permanence
Quinacridone Violet has excellent lightfastness and is considered the most lightfast organic pigment in this shade range.
Toxicity
Quinacridone Violet has no known acute hazards. Overexposure to quinacridone pigments may cause skin irritation. Quinicridone pigments contain a compound found to be a skin, eye, and respiratory irritant.
History
Although quinacridone compounds became known in the late 19th century, methods of manufacturing so as to make them practical for use as commercial pigments did not begin until the 1950s. Quinacridone pigments were first developed as coatings for the automotive industry, but were quickly adopted by artists.
Alternate Names
Quinacridone Red (PR192).
