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saltfire

updated thu 25 dec 97

 

WHITAKER on mon 22 dec 97

Any information on salt glazes would be greatly appreciated (Especially
using copper or rutile as a colorant, but also cobalt, ilmenite). I have
tried marbling in cobalt, manganese, yellow ochre, copper, chrome, etc.to
white stoneware bodies to ill effect (They mostly blacked over and the
images I had painted on the pieces were pretty much obscured).Also-
substitute for potassium nitrate (1.5%) in a glaze? Thanks so much!

Paul Jay on wed 24 dec 97

WHITAKER wrote:
>
> ----------------------------Original message----------------------------
> Any information on salt glazes would be greatly appreciated (Especially
> using copper or rutile as a colorant, but also cobalt, ilmenite). I have
> tried marbling in cobalt, manganese, yellow ochre, copper, chrome, etc.to
> white stoneware bodies to ill effect (They mostly blacked over and the
> images I had painted on the pieces were pretty much obscured).Also-
> substitute for potassium nitrate (1.5%) in a glaze? Thanks so much!
Try using the oxides with just a little of your claybody (powdered) and
add enough water to make it like thin cream. Apply to your work when it
is just thrown/made or when you trim or it gets leather hard.
Cobalt=bule obviously, but when you apply rutile over that (or under)
you will get various shades of green. Try tests of different thichness
of application. It sounds like the black pots are from over saturation
of oxides, sometimes "less is more"