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toxic stuff, barium?

updated sun 7 mar 99

 

Monona Rossol on fri 5 mar 99

---------- Forwarded message ----------
Date: Thu, 4 Mar 1999 07:37:28 EST
From: "Thonas C. Curran"
To: CLAYART@LSV.UKY.EDU
Subject: Re: toxic stuff, barium?, food-safe...questions
----------------------------Original message----------------------------
Gurus all: I know that some schools have replaced Barium Carbonate with
Barium frits in their glaze recipes. Now that's great since it's
better not to have rat poisons around, but is there any literature on
barium frits? Things I have read about barium have usually been
fiercely pro or con and have not cleared up the question. OK, you make
a frit to render the soluble insoluble and to render harmless injurious
stuff, etc., but can't a fritted glaze still leach nasty things if
weirdly compounded? Inquiring minds want to know... cnc
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Fritting barium or any other metal was intended to provide thorough mixing of
the ingredients and to make the frit safer to handle than the raw compounds.
It turns out that frits are not necessarily safer to handle than the raw
compounds and there is no relationship between frit solubility and the
solubity of the final glaze.

Monona Rossol
ACTS
181 Thompson St., # 23
NYC NY 10012-2586 212/777-0062

hal mc whinnie on sat 6 mar 99

i would like to agree with mona.
i did a paper on barium glazes last year which i sent to claytimes and i
thought they were going to print it.

maybe it will still appear.
in that paper i suggested some tri-axel glaze tests to determine the
minium amounts of barium needed for colors especially blue and use other
chemcials for matt effects such as whiting, kaolin,magnesium, or lithium
hal mc whinnie institute for arts education digitial