I have fired this glaze on a variet of clays and woodfired it: (same glaze on pots in my profile pict (longer all locust firing)
The backs are brown/amber probably like it would look in an electric or gas reduction but the face that gets ash (and more heat) turns into a nifty blue/green sometimes with amazing hare's fur effects.
So what is happening chemically on the ash face?
Is the ash adding silica and ergo diluting the ratio of the RIO ( as in a temoku iron reduction moving towards a celadon?
or is it adding oxides that are reacting?
Is behaving differently because of the additional heat on that side ?
.. and most importantly: how can I change this glaze to behave like this all around the things, all the time?!? Less iron, more gerstley /gillespie ?
It's from John Britt's high fire glazes:
Custer Feldspar: 44.00 Grams Silica: 12.80 Grams Whiting: 17.70 Grams Ball Clay (OM-4): 6.10 Grams Red Art Clay: 11.10 Grams Bone Ash: 2.00 Grams Talc: 3.80 Grams Gerstley Borate: 2.50 Grams Red Iron Oxide: 4.10 Grams
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