Glass pots come in a variety of sizes, it all depends upon how much
glass is wanted! Typical sizes are about 0.6m diameter and about 1.2m
high with a domed top and small opening on one side to allow the glass
blower to insert the blowpipe.

They have to be made from a very finely ground fireclay with no iron
impurities - due to their high operating temperature iron impurities
would melt, creating a hole in the pot!

There is a firm near Halifax that still makes glasspots (the only one
left in the UK as far as I know) using locally mine material. It not
only makes them for UK use, but also ships them all over the world.

They also make modern glass casting hearths. 

>I am not sure if I can ask this, but does any one have a picture of a glass
>pot in tact, they used to melt silica or sand in them to make glass, I have
>access to the only piece of pot to contain a very small amount of glass
>gall, or as you would know it as slag etc. In the country, this a friend has
>at the moment, trying to get him to put it in a museum in Nottinghamshire. I
>have also got a piece of the pot side. I have written a report on glass
>making in the village in the 1600s. any one is welcome to it free of course.
>
>Regards Bryan.

Cheers

Kelvin Lake
Shropshire Caving & Mining Club      ^o^
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