Trends in Colouring Blue Glass in Central Europe in Relation to Changes in Chemical Composition of Glass from the Middle Ages to Modern Age

Abstract

The study deals with the development of the chemical composition of blue glass from the 13th to the 19th century in the region of Bohemia (Central Europe). Nearly 100 glass samples (colourless, greenish, and blue) were evaluated by an XRF method to distinguish the colouring components of blue glass. As early as in the 13th century, blue glass based on ash containing colouring ions of Co and Cu was produced here. To achieve the blue colour of glass, a copper-rich raw material was most likely applied. This information significantly complements the existing knowledge about glass colouring in the Middle Ages, as the glass of later periods was typically coloured with raw materials containing cobalt.

Keywords

• blue glass
• smalt
• Bohemia
• Europe
• Middle Ages
• Renaissance