Graal glass

Graal glass is a decorative technique developed at Orrefors in Sweden in 1916. A design is worked into a coloured glass parison before it is reheated, cased in a thick layer of transparent glass and blown to its final form.

The design inside the glass

The decoration may be cut, engraved or etched into the coloured parison. After casing and further blowing, the motif lies within the glass body. Its form and proportions can change during inflation.

Confusion

Graal should be distinguished from ordinary cased glass that is cut only after cooling, and from painted or enamelled surfaces. An encased design alone does not establish maker or age. Examine signature, form, technique, wear and documented comparisons. Later glass artists have also used related methods.

Source: Corning Museum of Glass, Graal.