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high fire terra sig?

updated fri 24 oct 97


NAME on sat 4 oct 97

has anyone ever fired terra sig to cone 6 ox or reduction? I would be intereste

Thanks in advance,

Jeff Schmuki

Louis Katz on sun 5 oct 97

I have taken sigs to cone ten. They still can retain a buttery surface, but
the sheen will disappear. Bec areful some sigs will melt at higher temps,
and normally a sig melts before the material it is made from.
Case in point, I used to use a Redart sig on a straight 100 percent redart
casting body and when the body was still red the sig was glossy and from

Watered down sig used as a dip so that it accents the texture is a staple
of some potters from the Mengei Sota school. It works really well in wood
and residual soda/ssalt.
Some sigs that stick to the clay before it has reached maturity may comeoff
as the body shrinks.

My best advice is to try it.

Vince Pitelka on sun 5 oct 97

>has anyone ever fired terra sig to cone 6 ox or reduction? I would be
>Jeff Schmuki

Jeff -
In high-fire it is not possible to preserve the high shine which is possible
at low-fire temperatures. But that does not preclude the possibility of
using terra sig to advantage at high fire. Of course you must use a clay
which is refractory enough for high fire. In other words, if you use a
redart sig, it will turn into a glaze at high fire. But if you use a sig
made of ball clay, stoneware clay, or kaolin, you can apply it to lid seats
and bottoms if you wish, and it will give a smoother, more satiny surface.
Personally, I do not like to screw around with those surfaces. I like for
the clay to show through. It is in there, and I want people to know what it
is and what it's like. But each to his/her own on that issue.
- Vince

Vince Pitelka -
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166

Anita M. Swan on tue 7 oct 97

I've been testing some effects with terra sig fired to ^6 on
porcelain. The pieces were carved after the terra sig was applied and
burnished, leaving some porcelain surfaces showing. Fired to ^6ox the
terra sig lost most of it's burnish but still had a bit more sheen than
the unglazed porcelain. I used 2 colors of terra sig - one made with
Kentucky ball clay and the other with redart. My white ball clay terra
sig came out a soft yellow - very nice, and the red was a rather bright
yellow-orange. I glazed one piece with clear gloss - ho hum rather
boring. I pit fired one of the red terra sig pieces after it had been
fired to cone 6 - wonderful color variations but of course they are all
on the surface since the porcelain had vitrified. All in all I like
terra sig best when it is bisqued to ^08 and pit fired.

Anita in Southern Maryland where it's a bit warm for October!

> has anyone ever fired terra sig to cone 6 ox or reduction?
> Jeff Schmuki