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Current time:0:00Total duration:2:07

Glassmaking technique: core-formed glass

Video transcript

(music) Voiceover: The earliest glass vessels are core formed. Created by gathering molten glass around a solid core. To make the core a mixture of dung, clay, sand and water is kneaded together to the consistency of bread dough. This is formed in the shape of the inside of the object to be made. Then attached to one end of a metal rod. (music) After drying, the core is given it's final shape by trimming and filing. Anklets of glass are melted in a crucible within a furnace. The core is coated with the molten glass. Turning the rod ensures an even coating. Decorative threads of different colored glasses are added by trailing. After reheating the glass, the threads are combed or raked. with a pointed tool. (music) Pincers are used to form the neck and the rim. Suspension loops are made by adding a small bit of glass to the side of the vessel. Then manipulating it again with the pincers. (music) After completion of the glassworking, the rod is removed by giving it a sharp blow. Once the vessel has been cooled slowly, the core material can be scraped out, leaving behind the vessel cavity. (music)