Tom Cooper on wed 8 may 96
Dear Clayarters,
A friend of mine is having a problem with an old reliable glaze and she
asked me to query the group as to possible causes. It is a ^9 semi-gloss
that is fired electric. Normally it has a really smooth, buttery surface.
The last batch however has a gritty, sandy feel. You can actually see
particles in the glaze about the size of fine sand. She recently got a new
bag of Potash feldspar (Custer) from Standard Clay, and that is the only
ingredient that has changed. She screens twice in an 80 mesh. Could the
Custer be creating this snady grit? It's nasty. Here is the recipe. Let me
know if you have any suggestions.
Flint 15.2
Potash feldspar 38
Whiting 21
Kaolin 20.2
Titanium dioxide 4.1
Cobalt carb. 1.5
Thanks, Maribeth in Michigan, where I know spring is coming 'cause the
Magnolia trees are about to burst!
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