creation

hollow knop

Glassmakers blow glass bubbles slowly. The bubble can have relief decoration on the outside. Ridges are formed when the glassmaker slowly blows the bubble into a mould. A small bubble is blown and pressed into an optical mould. In Italian this is known as stampa: the glass is stamped into the mould, creating ribs on the exterior. The small bubble is attached to the avolio – a spool-shaped piece of glass – at the underside of the glass and formed into a rounded stem section. Glassblowers leave traces of organic material, bodily fluids and other residues inside the sealed bubble. When hot glass comes into contact with such substances, a strong reaction can occur, making the glass less stable.