Blue glass with prunts, ca. 1510–1530
Blue glass, blown, applied
(H x Ø)17,6 × 12 cm
Place foundMainz
About the workProduced by travelling glassworks in Central European forests, “forest glass” is usually green. The reason for this is the contamination of the raw materials with iron oxide, which in its two “oxidation states” gives the glass a yellow or a pale blue colour. Since both oxidation states are normally present in the glass, it appears green as the result of the two colours mixing. The colour can be controlled in the kiln by regulating the oxygen supply. In the case of this prunted cup, copper oxide was probably added, which in turn results in a more intense blue colouring depending on the oxygen levels in the kiln.
AccessionKarl Amendt collection, permanent loan since 2005
Inventory numberLP 2010-40