Tommy Humphries on fri 7 apr 00
Was informed today that couldn't label pots utilizing zinc bearing glazes as
lead free due to the presence of lead. After checking the bag for analysis
found that it was 99.9 zinc oxide plus enough lead and cad. to still not add
up to 100%. Glaze has been tested for leaching, and always come out
negative.
Do you think that this minuscule amount of lead should be taken into
consideration when labeling pots?
Tommy Humphries
"`You know, it's at times like this, that I really wish I'd listened to what
my mother told me when I was young.'
`Why, what did she tell you?'
`I don't know, I didn't listen.'"
(Douglas Adams)
----- Original Message -----
From: Mary
To:
Sent: Thursday, April 06, 2000 1:26 PM
Subject: Re: Back to pottery
> ----------------------------Original message----------------------------
>
> > I regard to your glass work: I, too, have become enamored with fused and
> > slumped glass, and would love to know just how to use my regular ceramic
> > kiln for that. The glass kilns have elements in the lid for more even
> heat,
> > but I understand we can adapt our kilns, too, by using only one layer
and
> > firing very low, by our standards, like cone 017. Would love any
> suggestions
> > you have along these lines.
>
> Pam,
>
> Thanks for your encouragement. I have been invited to sit in a glass
studio
> locally, and watch a man whose speciality is glass fusion and bead making.
> He uses both a glass kiln and a clay kiln, and swears it can be done. I
have
> heard of others who have done the same, but from what I gather, they have
to
> open and close the lid to anneal the glass, which sounds like far too much
> work and babysitting for me. I am as curious as you are to see if there is
a
> straightforward way to do glass in this manner, without having to tend to
it
> so diligently.
> I'll keep you posted privately, unless someone else is interested.
>
> Mary
> Jax. Fl.
>
Cindy Strnad on sat 8 apr 00
Tommy,
I don't think I'd worry about it, but you could always just label it "food
safe".
Cindy Strnad
earthenv@gwtc.net
Earthen Vessels Pottery
RR 1, Box 51
Custer, SD 57730
Ray Aldridge on sat 8 apr 00
At 01:15 PM 4/7/00 EDT, you wrote:
>----------------------------Original message----------------------------
>Was informed today that couldn't label pots utilizing zinc bearing glazes as
>lead free due to the presence of lead. After checking the bag for analysis
>found that it was 99.9 zinc oxide plus enough lead and cad. to still not add
>up to 100%. Glaze has been tested for leaching, and always come out
>negative.
>Do you think that this minuscule amount of lead should be taken into
>consideration when labeling pots?
>
>
No, is my opinion. I don't use zinc, because it's a lumpy pain in the ass
to work with, but I can't see this as a realistic concern, especially if
you're firing to stoneware temps-- far above the boiling point of both lead
and cadmium. Even if the zinc contains a thousandth part of lead, few
glazes need a whole lot of zinc. If your glaze contains 10 percent zinc,
you're down to one ten thousandth of lead in the glaze, *before* firing.
.0001?
Someone check me on the arithmetic, because I'm casual.
Ray
Aldridge Porcelain and Stoneware
http://www.goodpots.com
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