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Special topics in art history
Course: Special topics in art history > Unit 2
Lesson 13: Mosaic, metalwork and glass- Ancient and Byzantine mosaic materials
- How was it made? Micromosaics
- Medieval goldsmiths
- An Art of Attraction: The Electrotyping Process
- Glassmaking technique: free-blown glass
- Roman mold-blown glass
- How stained glass is made
- Stained glass: history and technique
- The conservator's eye: a stained glass Adoration of the Magi
- Enamelling
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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.
Want to join the conversation?
- How does the glass get colored?(15 votes)
- Color is added to the glass a few different ways. Colored powder, frit (small chuncks of colored glass), or rods of colored glass. The color is added before the piece is broken off the blow pipe and attached to the punty.(8 votes)
- @"It can then be gradually cooled in an aneeling(?) oven." 1:45
What kind of oven is used for cooling? How does it work? Have I spelt it right?(12 votes)- Is Dale Chulie's glass blowing studio on video for educational review?(1 vote)
- Why doesn't the hot, liquid glass simply fall off of the rod? How does it stay attached? Also, what if the glass blower blew a bubble too large? Would the glass bubble pop like a real bubble?
These are really science questions, but i'm just wondering if anyone out there knows...(13 votes)- The pipes are preheated before you use them because glass sticks to things that are hot, if they were too cool the glass wouldn't stick. To answer your question about the bubble, it would't pop like a normal bubble would. The larger you blow a bubble the thinner the glass gets and the faster it cools, if the glass cools too quickly it will shatter so most often with large bubbles they will simply crack..(7 votes)
- is true that glass does come from the sand?(5 votes)
- Yes, it is true! When you heat sand to 3,200 degrees Fahrenheit it becomes glass.(9 votes)
- Why was the video so short i wanted to see more!(6 votes)
- The Corning Museum of Glass has TONS of videos. Check out their youtube account for many more videos on glassmaking!(6 votes)
- It's amazing. But what I really want to know is... How this technique was discovered and when? Thank you!(7 votes)
- The history of glassmaking can be traced back to 3500 BCE in Mesopotamia. From Wikipedia http://en.wikipedia.org/wiki/History_of_glass(3 votes)
- What is the glass made of ,exactly.(4 votes)
- Silica, the main component in sand! Historically, glass was actually made from sand, and when thunder hits sand it forms glass. Cool, right?(5 votes)
- How long is a normal blow pipe?(6 votes)
- The beginning of the video does not discuss where the molten glass comes from. Where do the 'ingredients' for glass come from and how are they 'mixed' and prepared to form the actual molten glass?(3 votes)
- The raw materials mixture for glass melting is termed "batch". The raw materials used are sand, trona, lime, albite, orthoclase, dolomite, and borax. "Batch" comes in powder, block or pellet form and is melted down in the furnace. The furnace is anywhere between 2200 - 3000 degrees F. and is a big "pot" of clear glass.(3 votes)
- I always wonder who was the first person to come up with the idea of glassmaking. Was it by accident or was it intentional after making observations about natural phenomena. I wonder if we have any historical evidence about that or even just a legend.(2 votes)
- Wonder no more! You can find the history of glass at: https://en.wikipedia.org/wiki/Glass#History_of_silicate_glass(3 votes)
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)