Roman mold-blown glass
About this video
Roman glass makers used molds to make matching vessels, like a pair of glass flasks. Molten glass is inflated in a mold to take its shape, then removed, its bottom flattened and neck shaped, attached to a pontil, and reheated for final refinements.
You'll be able to
- explain why glass makers used molds.
- put the main steps of making a mold-blown vessel in order.
- describe what a pontil is used for.
Key words
- mold
- A hollow form that glass is blown into so it takes that shape.
- duplicate
- An exact copy of something.
- pontil
- A rod attached to the bottom of a vessel so it can be held after it is freed from the blow pipe.
- inflating
- Blowing air in so something gets bigger.
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)
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