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fwd: re: semi -matt ^6 glaze

updated thu 31 oct 96


Nancy Jervey on fri 4 oct 96

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Date: Thu, 3 Oct 1996 08:52:13 -0700 (MST)
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From: (Michelle H. Lowe)
To: Nancy Jervey
Subject: Re: semi -matt ^6 glaze
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In article <>, Nancy Jervey wrote:

> Could anybody please tell me the ingredient in a ^6 glaze that make
> the glaze glossy. I would like to change a glossy ^6 glaze to a
> semi-matt glaze. Thanks Nancy

I'm afraid it's a bit more complicated than that Nancy. Putting it very
simply, glazes are made up of three different "parts".
1-the glassmaker-which is usually silica (also known as flint)
2-the refractory-which keeps it from falling off the pot (alumina, usually
clay in the recipe)
3-the flux-which is the part that makes the glaze melt

The third part, flux, is usually a combination of different materials,
calcium, magnesium, lithium, strontium (etc. these are just a few
examples). Different combinations cause different glaze surfaces (matt,
glossy etc.). There is also the issue of "eutectics" which means that
different chemicals which melt at certain temperatures alone, react
differently when melted *together* and might have a much lower melting
point together than they each do alone.

So, depending on the specific glaze recipe, there would be different
methods of attaining semi-matt and the color might change with the
adjustment as well. You might try posting the actual recipe for our
resident glaze gurus to give it a shot (Hi Tom ;).

Mishy, not a glaze guru but has a basic understanding of the chemistry involved

Michelle Lowe, potter in the Phoenix desert \|/ | -O- | | /|\ | | |
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