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tapioca ; rutile

updated tue 22 feb 05


Lili Krakowski on sun 20 feb 05

It was a good question whether the tapioca was "raw", the instant kind, =
or cooked. Each would absorb and hold water differently. Among other =
considerations, how dense is your clay body? If you are going to =
introduce stuff that may trap moisture-- i.e the foreign material is =
still damp while the clay around it has dried and closed off =
"chimneys'-- you might as well send out engraved invitations to =

Assuming the body is dense then experiment with adding sand or grog with =
the tapioca. If the explosive tapioca was uncooked try some cooked =
tapioca. My guess would be you might have better luck with fully cooked =
tapioca that you then allow to air dry --on a plate or board, flat =
out--before inclusion.

And, as said, bisque slowly. I mean slowly. And do a few tests first, =
do not commit a whole kiln to experimentation.

As to rutile. Ilmenite and rutile are closely related, but ilmenite has =
a lot more iron. Ilmenite, the books tell us tends to act as a "seed" =
around which crystals may form. So with ilmenite some form of breakup =
in the glaze surface will occur. And then ilmenite can be ground to a =
fine powder or be sold as "granular". Meanwhile back on beach, rutile =
is not a sure thing. We all have had experiences with cobalt, with iron =
that this batch is not as "powerful" as that batch. If you are =
disappointed that you got some sort of nasty tan instead of caramel =
cr=E8me then try mixing your rutile with some straight titanium ox--the =
refined stuff. Or you can blend titanium , rutile and ilmenite....

Last--here I go again--if you used a recipe that your school used EXPECT =
different results. You x years ago, at the time the potash or soda spar =
was one no longer to be had, this was colemanite they used, not GB, not =
a current ersatz--and they had had both the spar and the colemanite for =
15 years....ALWAYS expect that an old glaze recipe will need =

Last: I have always been under the impression that those lovely little =
translucent spots on porcelain are made by pressing rice grains into the =
damp clay....they then burn out in the fire. They were not, as I =
understand it, made by including rice grains in the clay body.

And last: I am one of those who love tapioca pudding. Horn & Hardard =
made the best--and that was my pay day treat many years ago...

Lili Krakowski

Be of good courage