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Glassmaking technique: free-blown glass

Creating a free blown glass bottle involves gathering molten glass on a blowpipe, shaping it on a marver, and blowing a bubble. The bubble is stretched into a tube, inflated to form the vessel body, and the bottom is flattened. The mouth is shaped using a pontil, and after a reheating, the opening is reshaped. The finished vessel is then cooled in an annealing oven. Created by Getty Museum.

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Video transcript

(soft flute music) Voiceover: Free blown glass vessels are shaped solely by inflation with a blowpipe and manipulation with tools. (soft flute music) To make a simple bottle, molten glass is gathered onto the blowpipe, then rolled back and forth on a smoothed surface, the marver, to give it a cylindrical shape. (soft flute music) A small bubble is blown in the glass. The blowpipe is spun end-to-end in order to stretch the bubble out to form a long narrow tube. The thick mass of glass at the end of the tube remains soft and is immediately inflated to form the vessel body. (soft flute music) The bottom is flattened. (soft flute music) To shape the bottles mouth, a glass-tipped metal rod, the pontil, is attached to the bottom of the vessel. (soft flute music) Drops of cold water are applied and a sharp bang on the blowpipe causes the neck to break. (soft flute music) After reheating, the opening can be reshaped. (soft flute music) A gentle tap on the pontil easily breaks the finished vessel free. (soft flute music) It can then be gradually cooled in an annealing oven. (soft flute music)