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Roman mold-blown glass

Glass makers create duplicate vessels using molds. They start with molten glass, inflate it in the mold to take shape, then refine the bottom and neck. A pontil is attached, the vessel is freed, reheated, and further shaped. Created by Getty Museum.

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Video transcript

Narrator: Glass makers use molds to create duplicate vessels such as this pair of glass flasks. The process begins by placing molten glass into a mold. By inflating, the glass takes the shape of the mold. Once removed from the mold, the bottom is flattened and the neck shaped. A pontil is attached to the bottom and the vessel is freed from the blow pipe. The vessel is reheated and further refinements are made to its shape. (silence, showing example)