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Course: The J. Paul Getty Museum > Unit 2
Lesson 1: Ancient glassmaking- Glassmaking: history and techniques
- Ancient glass at the Getty
- Glassmaking technique: mold-blown glass
- Roman mold-blown glass
- Glassmaking technique: core-formed glass
- Glassmaking technique: free-blown glass
- Glassmaking technique: mosaic glass
- Glassmaking technique: gold glass
- Glassmaking technique: cameo glass
- Glassmaking quiz
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Glassmaking technique: mold-blown glass
Mold-blown glass is made by blowing hot glass into a mold made of clay, wood, or metal. Watch a glassmaker use a mold with incised designs (footage from the Corning Museum of Glass). Created by Getty Museum.
Want to join the conversation?
- Wouldn't the hot glass stick to the inside of the mold?(13 votes)
- the glass is both flexable and not too stiky. So, it is like a rubber(5 votes)
- At0:50, it looks like the glass is liquid. A molten hot liquid. Why is it not dripping or flowing?(4 votes)
- What you saw is indeed liquid but it's too viscous to drip. I am sure other things affect it too like surface tension.(4 votes)
- How hot does glass need to be to be "blown"?(2 votes)
- It depends. Usually around 700-800 degrees if you need a kiln, I think(2 votes)
- If how hot is the glass? If it is put in a wood mold wouldn't it burn the mold or at least make scorch marks?(2 votes)
- why does the melted glass look edible(2 votes)
- how can to get the stuff to do glassmaking(1 vote)
- how do you get the stuff to make glass(1 vote)
- I watched the video, but didn't earn energy points.Why?(1 vote)
- If you watched the entire video and didn't earn any energy points I would report it in the help center.(1 vote)
- What is the most common mold?(1 vote)
- How many molds are there?(1 vote)
Video transcript
(Chinese music) Voiceover: Mold blown
glass is made by inflating molten glass in a mold normally made of clay, wood or metal. In the dip mold process,
a gather of hot glass is lowered into the mold. As soon as the glass
touches the bottom of the dip mold, air is blown into the blow pipe. The grooves inside the
mold pattern the glass. However much the bubble is
further inflated and shaped, the impressions from the mold
will remain in the glass. If the tip of the bubble
is held with pincers and the blow pipe is turned, the pattern becomes twisted. Molten glass can also be
inflated in a closed mold made of multiple parts. An elongated glass bubble
is placed between the open halves of the mold. The mold is tightly
closed and air is blown forcefully into the blow pipe. When the glass hardens, the mold is opened and the glass worked free. Closed molds can be used again and again, creating many vessels with the same shape and decoration. (Chinese music)