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raku results

updated fri 24 oct 97 on wed 8 oct 97

On Sunday, I tested some raku glazes that I got from either Clay Art or
Ceramics Monthly. I use an electric kiln and eyeball (wearing welder's
goggles) the glazes rather than using the kiln sitter or pyrometer. (I bought
a pyrometer from Bailey, but haven't figured out how to attach the probe!)

I use Standard Clay - either 213, cone 6 porcelain or 365,cone 6 grolleg
porcelain. I normally reduce in garbage cans filled with shredded paper from
my office. On Sunday, I also included some cedar chips used for animal

My great discovery on Sunday was the difference between a fast pull and a
slow pull. I created two glaze samples. In the first load, I pulled the
sample first. In the second load, I pulled the glaze samples last. Had I not
created the samples at the same time, I would have thought that I mixed up
the samples. The difference was night and day.

The results:
Tsuya's mistake (ClayArt 8/28/97)
fast pull - semi shinny copper
slow pull - hard to describe. appears to be matt, interesting flashing.
shinny on the edges where there was a thinner coat?

Carls Copper Sand (ClayArt 10/10/96)
fast pull - sandy copper with lots of colorful flashing. matt alone, shinny
when covered with a coat of red/green (ClayArt 10/10/96)
slow pull - matt bluish with a tinge of yellow alone. shinny yellow blue with
a coat of red/green.

Chris Thompson's Black (ClayArt 7/4/97) without the Manganese Dioxide
fast pull - my favorite. shinny copper with lots and lots of color burgundy,
blues. slightly sandy.
slow pull - shinny blackish blue with shades of yellow. (less attractive than
it sounds)

Magical Mystery (ClayArt 12/11/97) based on weight rather than volume
fast pull - burgundy/blue flashing, sort of alligator-like, matt. with a coat
of clear crackle over it, more colorful. shinny copper/blue/burgundy
slow pull - black with some possible color flashes. with clear crackle, not
as black.

Very dry matt burgundy red ( ClayArt 5/14/97)
fast pull - copper/burgundy rough surface with some possible blue flashing.
slow pull - semi-glossy, slightly sandy white/turquoise.

Red/Bronze (Marcia Selsor, 5/97 CM) used Gerstley Borate rather than
fast pull - very shinny copper & turquoise.
slow pull - shinny turquoise over white.

Dry Alligator (Marcia Selsor 5/97 CM) used Gerstley Borate rather than
fast pull - sandy, matt, burgundy/copper/blue/yellow. seems to have great
potential to become another favorite of mine.
slow pull - sandy, semi-shinny blue with tinges of yellow.

Volcanic Ash plus 2% Copper Carbonate (ClayArt 4/20/97)
fast pull - shinny, watery turquoise on white. slightly sandy.
slow pull - shinny, sandy blue/yellow with copper

Hasselle Copper Matt (Robert Hasselle, 1/97 CM)
fast pull - very matt, more burgundy than copper. no flashing.
slow pull - hard to describe since the sample was rather small. may be either
very ugly or potentially very interesting. sorry!

Post Pac Man (Robert Hasselle, 1/97 CM)
fast pull - sandy, semi-shinny, burgundy/yellow, blue/copper.
slow pull - shinny, sandy blue with yellow tinges.

I'm looking forward to more experimentation.

with a cold in warm, sunny Baltimore, MD USA

Carol Ratliff.clayart.CLAYART.MAILING LIST on fri 10 oct 97

Thanks for your glaze results......I've been testing too so found the results
I dare you to repeat your results and come up with the same thing
twice.......a further challenge would be to test on top and bottom shelf - we
had a glaze that wouldn't melt on the bottom shelf at temp when others did.
Ain't testing fun?
carol ratliff