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ash glaze -micro-crystal - controlled cooling - fact check

updated thu 29 apr 04


Earl Brunner on tue 27 apr 04


Classic example if a microcrystalline glaze that needs slow cooling to be
Cone 10-12 Mat from Glen Nelson's Ceramics: a potters handbook.
P. Spar 40
Whiting 22.3
Kaolin 21
Silica 16.7
Titanium Ox 4.4

This glaze was ALWAYS mat in the Alpine kiln at school.
Without firing down, it was ALWAYS glossy in my downdraft I built that had a
brick up door. The brick up door just leaked air and let it cool too fast.

Earl Brunner
Las Vegas, NV

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of John
Sent: Tuesday, April 27, 2004 10:40 AM
Subject: Re: Ash glaze -Micro-crystal - Controlled cooling - fact check

On Monday, April 26, 2004, at 06:43 AM, May Luk wrote:

> From my participation with clayart and my glaze studies, I managed to
> say:
> "maybe controlled cooling?" Another very experienced potter, who is
> also a
> ceramic tutor spoke with authority [a man potter!] saying, it has
> nothing to
> do with the cooling, it has to do with blah blah [at this point, I
> blanked
> out with what he said about "blah blah", because of his tone of
> voice.] He
> went on to say, it's micro-crystal, that has nothing to do with
> cooling;
> Only large crystal - as in zinc silicate crystals requires slow
> cooling.