you refire high enough to make the glaze run a little you get a
beautiful lacey pattern, not crackle, but something different
and according to him, desirable.

Richard Behrens is inclined to get complicated, too, even to
going to the trouble of spraying or sprinkling a very hot pot
with cold water to develop a crackle. My experience has been that
it's much easier than that to come up with a crackle - if I had
@ glaze that was that hard to make craze I think I'd be inclined
to just leave it be! However, whether you use his method of
getting a crackle or just have a pesky glaze that crazes no
matter what you do, you might like to try his method of coloring
the cracks, which is to heat the pot above skin-handling temper-
ature and then immerse it in a 5% solution of one of the various
soluble colorants, such as cobalt nitrate, copper nitrate, iron
nitrate, etc.. According to him, as the pot cools a vacuum is
created by the condensation of the steam in the cracks and the
solution is thus pushed into the cracks. When the pot is dry,
wipe off the thin excess coating with a damp sponge and refire
to about cone 018. The salts decompose and fill the cracks with
colored oxides.

Robert Fournier is much more down-to-earth even to giving a
formula for a crackle tale glaze and suggests staining the crackle
with manganese or other colour while still hot from the kiln.
(That rather baffles me - you'd have a lot more cracks to stain if
you just waited a while.If the pot needs to be hot to open up the
cracks you could reheat it.) He gives credit to Victor Margrie

For the following glaze formula:

Tale Crackle Glaze:

KO 0.20 Al,O, 0.20 sid, 2.0
CaD 0.29
MgO O.51

Firing to 1260° C used on David Leach porcelain body:
Grollegg china clay powder 53
Potash feldspar 25
Water-ground quartz 17) «6<(flint, to us)
white bentonite ="

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