Special topics in art history
- 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
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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- How do the tools and materials used today differ from the ones used by the Romans? Are the techniques fairly similar?
- I have seen some modern day glassmakers in person while visiting Halifax & again in Quebec City. If you ever get a chance to see in person go check it out! It seems that the techniques are very similar. I found that the modern day glass items are a bit more refined &/or symmetrical when compared to a lot of the older pieces that I have seen. A lot of great information about how the Romans made glass at this website http://www.romanglassmakers.co.uk/(2 votes)
- How did the Romans learn or discover how to make glass?(3 votes)
- Perhaps the Corning Museum of Glass might have an answer for you.
The information in the following link may or may not be correct
Little is known about the first attempts to make glass. However, it is generally believed that glassmaking was discovered 4,000 years ago, or more, in Mesopotamia. The Roman historian Pliny attributed the origin of glassmaking to Phoenician sailors. He recounted how they landed on a beach near Ptolemais (in modern-day Israel), propped a cooking pot on some blocks of natron (a naturally-occurring alkali substance) they were carrying as cargo, and made a fire over which to cook a meal. To their surprise, the beach sand beneath the fire melted and ran in a liquid stream that later cooled and hardened into glass. Though this is an interesting explanation, this scenario is not possible since a cooking fire cannot reach the melting temperature of glass, and the story most likely involved Ptolemais because its beach sand was historically known to be heavily used for glassmaking.
Scholars believe that the ability to make glass developed over a long period of time from experiments with a mixture of silica-sand or ground quartz pebbles - and an alkali. Other high heat industries, including ceramics and metalworking, could have inspired early glassmakers. Perhaps the development of glass began with potters firing their wares. Could the first glass have been colorful, hard, shiny decoration fused to a clay pot's surface in the heat of the furnace? No one knows.(5 votes)
- How did the Romans get the glass, and how did they get the fire hot enough to melt the glass?(2 votes)
- To make glass, they probably smelted sand in the fire and made glass
To answer your second questions, they must have used a lot of wood to burn(3 votes)
- Hi, This was extremely interesting. I was surprise when he placed the hot glass bottle on his leg for the final touch's to the bottle. 1] Where did he get the glass mold? 2] What temp. F was the glass furnace set? 3] Is this glass furnace capable of mass production? 4] What is the cost of using the furnace? P.S.-Thanks.(3 votes)
- Temperatures are usually kept above 2000ºF for blowing. Depending on use and size, furnaces typically hold between 50- 1000 lbs. The cost to maintain and heat the furnace is very high since they are kept running 24 hours a day.(1 vote)
- Does the pontil (sp?) attach to the glass via suction?(1 vote)
- No. The pontil is hot, and has molten glass on it. The molten glass attaches by melting onto the hot glass of the bottle, It's like being welded on. See: https://en.wiktionary.org/wiki/pontil(1 vote)
- How did they make the mold?(1 vote)
- You make the glass molds by carving into two pieces of clay, making a kind of hollow into the middle where the glass will be blown into. Then you put the two pieces together, making them AIRTIGHT (otherwise the glass will seep into little air bubbles that are left and get messed up). And you have a glass mold! If you want some more info on this topic, go to http://www.glasscampus.com/tutorials/pdf/mold.making.for.glass.art.pdf. They also have some clay-making tips and advice. Hope this answered your question!(1 vote)
- Are the blow pipes mouth blown or is a pump used similar to a fire stoker?(1 vote)
- The blow pipes are mouth blown, this gives the glass makers much more control. If you haven't already watched this https://www.khanacademy.org/partner-content/getty-museum/antiquities/ancient-glassmaking/v/glassmaking-technique-free-blown-glass this video shows that.(1 vote)
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)