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1. chrome toxicity 2. breaking maroon

updated sun 5 apr 98


Vikki Dow on sat 4 apr 98

#1. I've read that chrome is definitely carcinogenic, and have therefore
tried to avoid it completely, yet it seems every time I hear of a glaze I'd
like to try, it has some amount of chrome in it (I'm striving for an
emerald green and a maroon in ^10 Ox.). My questions are: In what way is
it carcinogenic - i.e., is it the dust, so if I take the necessary
precautions, once it's fired in a "durable" glaze, it's ok? Or is it only
toxic if it leaches into food from a glazed pot? ??? Is there any "safe"
amount to use in a glaze (say, at ^10 ox.)? I've been avoiding it except
in mason stains, which I hoped were somewhat safer, but I gather from
recent posts that they're not. I've tried looking it up in some of the
books, but all I can find out is that it IS carcinogenic. Any info would
be appreciated!

#2. As mentioned, I'm working on finding a maroon glaze for ^10 oxidation.
I've tested several clear glazes with varying amounts of maroon-ish mason
stains, and found one combination that worked in so far as staying maroon
through the firing and not crazing, etc. However, it was a bit too plain.
I am new at glaze development, but I've read a lot on the subject and I use
Hyperglaze to keep the materials "within limits". I've read that I should
try titanium, boron or zinc to "break up" a glaze, but I've also read that
the maroon stains won't work with any of these. Those damn tempermental
chrome-tin pinks! Does anyone know of any material I could use with
chrome-tin pinks/maroon to break-up or mottle the glaze texture?

I promise that once/if ever I find the glazes I'm searching for, I will
share my results!
Thanks for all help.

Vikki Dow
Stilltree Pottery
Oakland, CA