Cobalt Glass

The deep brilliant blue of cobalt comes to life when it is used to color glassware. The realization of this fantastic connection resulted in the field of cobalt glass, which developed in Europe in the 16th century.

The oldest examples of cobalt glass date to the late third millennium and the days of ancient Mesopotamia, yet the pigment disappears from glassmaking following this point for generations. Though cobalt was used with increasingly frequency in painting ceramics from the ancient world on, it was not until the 16th century that pioneering glassmakers in Bohemia experimented with cobalt glass once more.

As time progressed, glassmakers came to enjoy the richness of color, as the cobalt itself filters out the inherent yellow cast of glass. Resulting by the 19th century was a wide variety of cobalt glass producers both in Europe and in North America, with a particular surge in American demand following the Depression era.

Quick Facts

• Cobalt, which is made from the chemical compound of potassium cobalt silicate, is also called smalt. Its chemical relative, cobalt aluminate, or cobalt blue, proved essential in painting. So prevalent was it in Maxfield Parrish's paintings, for example, that it became known as Parrish Blue
• In painted instances where the original smalt was used, such as in "The Portrait of Sir William Butts" by 16th-century German artist Hans Holbein the Younger, these zones of blue have typically oxidized and discolored over time
• Bristol blue glass, originating in Bristol, England, is one of the most popular and historic production regions of cobalt glass. Their glass makers created the iconic blue bottle still used to house Bristol Cream Sherry