Ron Roy on tue 17 feb 98
These comments and glaze were posted while I was away and I though they
deseved some comment.
At cone 10, the limit formulas I use tell me it is short of silica and
therefore durability is suspect. On the other hand there are no problematic
oxides present so it should not be a hazard. I might become dull (etched)
with time and use however.
At cone 6 it does have enough silica - it does have some extra CaO but not
enough to affect the durability much.
My point is - it's a better glaze at cone 6 than at cone 10.
It will craze on just about any body.
Lasse Ostman has a few glaze recipes on her website. One of these is S422
Semi matt golden yellow. She fires this to 1270 C with a one hour soak. It
is described as a very intensive golden yellow. I fire to a very full cone
6. I have never paid much attention to what cone a glaze is supposed to go
to (as long as it is from 5-10) and as a result have a few very nice glazes
that are being underfired. At cone 6 oxidation, this glaze is an
interesting pale yellow cream that pools and just has a very interesting
surface. I just tried it on a vertical test tile (usually I do most work
flat) and it was more in the tan range (just a little). But it was
impressive and would be worth a test on a small bowl. A very elegant glaze.
Here is the recipe:
Potash feldspar 64.35
albany slip 5.68 (I used Miller's/Laguna's albany
rutile 7.89 (I used the 325 mesh light
that US Pigment sells)
FeO spanish 6.31
It works fine single fired.
93 Pegasus trail
Canada M1G 3N8
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