R&F Encaustic Paint Block - Cobalt Blue, 40 ml

It is the “true” blue because it is distinct from Cerulean on the green side and Ultramarine on the red. When mixed with cadmium yellow, it makes muted greens.

• Pigment Composition: PB28-Cobalt Blue
• Paint Lines: Encaustic, Pigment Stick
• Opacity: Opaque
• Pigment Stick Drying Rate: Fast
• Classification: Synthetic Inorganic
• Chemical Composition: Cobalt aluminate
• Safety Information: Conforms to ASTM D-4236
• Safety Warnings: This product contains cadmium, a chemical known to the State of California to cause cancer.

Pigment Name: PB28-Cobalt Blue

Classification: Synthetic Inorganic

Chemical Composition: Cobalt (II) oxide + aluminum oxide

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 performance among various manufacturers.

Permanence

Cobalt blue is absolutely lightfast and extraordinarily stable. The stability of cobalt salts at high temperatures makes 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 reactions through contact with the skin. It is considered a possible carcinogen.

History

Since ancient times, smalt blue has been used to colour glass and ceramics. Cobalt salts, which give smalt its characteristic blue colour, were identified in the 18th century. Techniques for manufacturing Cobalt Blue, a chemically pure salt of cobalt and aluminum oxide, were developed in 1802.