PB73—Cobalt Blue Deep

Pigment Type

inorganic

Chemical Name

cobalt silicate blue olivine

Chemical Formula

Properties

Cobalt silicate blue olivine is a transparent blue pigment with low tinting strength.

Permanence

Cobalt silicate blue olivine is permanent and lightfast. Its stability at high temperatures has made it a favorite in coloring glassware and ceramics.

Toxicity

Cobalt silicate blue olivine is mildly toxic and a respiratory irritant, but less toxic than some of the other cobalt salts used as pigments. In liquid form it is not considered hazardous.

History

Cobalt silicate blue olivine is a cobalt salt that is frequently used as a colorant in glass and ceramics. It has been used in natural mineral forms since ancient times. Techniques for manufacturing Cobalt Blue, a chemically pure salt of cobalt and aluminum oxide, were developed in 1802. Synthetic processes for other cobalt salts, including cobalt silicate blue olivine, were developed in the 19th century.

Alternate Names

Smalt Blue, Cobalt Silicate.