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rainbow shinos

updated sat 15 jul 00

 

Craig Martell on fri 14 jul 00


Tony wanted to know:

>So Craig is this material of yours high iron. I figured that is what is
>making our shino go so nice.

Yes, it's got a fair amount. The analysis that I have says 8.135 per
cent. The iron is certainly contributing to the visual festivities but
there's more to it than that and it has to do with the glaze being able to
reflect light from both surfaces as in interior and exterior. The
phenomena is called birefringence and I have to thank Michael Banks for
hipping me to that stuff. I still don't have a good understanding of how
it all works but I keep reading.

I think that a good place to start with these irid rainbow shinos is to
take out all the kaolin and ball clay and replace that with an iron bearing
slip clay. I found 3 of them by doing an Ian Currie recipe grid biaxial
with Virginia Wirt's carbon trap fluxes in the flux corner of the tile and
then blending in the iron slip. Viola!!

later, Craig Martell in Oregon aka El Loco!.........or was that local?