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white crackle raku

updated fri 31 jan 97


Timothy & Lauren Loftus on wed 1 jan 97

We pull our white/clear crackle out, blow on it, or wait till we hear it
ping a little. The more it pings the more it's shrinking, I guess.
More=small crackle, less=bigger crackle patterns, (but not always).

Place pot in large aluminum tub of kiln dried pine shavings, cover it with
the shavings, and wait. You can check it by uncovering the pot a little. The
crackle should have plenty of carbon black embedded in the crackle.

If this sounds like what you are doing, then maybe it is your glaze recipie
that isn't quite right? Have you tried other recipies? The only times I
haven't had blacks in my crackle were very small pots that cooled too
quickly, but then, they didn't have dark carbon blacks in the unglazed
areas, either.

A recipie for white/clear crackle is:

65 Gerstley Borate
20 Neph Sy
10 Flint

Hope this helps. White crackle is my favorite. Also, for those annoying
mystery white spots on your carbon black unglazed areas, watercolor paint
(Windsor & Newton?) in Lamp Black will give a nice matte black when mixed
with water and painted on in experimental washes.

Lauren Loftus

Gerry Punt on thu 2 jan 97

It is my exerience that if you bisque fire to hot, or raku fire to
hot that clay body will not absorb as much carbon, leaving a blueish gray
color instead of the black. might explain the lack of black in cracks.
or the return of the " Cat in the hat".

gerry punt