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monona on: aluminum leaching (fwd)

updated thu 13 apr 00 on wed 12 apr 00

> ---------- Forwarded message ----------
> Date: Tue, 11 Apr 2000 15:23:39 EDT
> From: Ray Aldridge
> Reply-To: Ceramic Arts Discussion List
> Subject: Re: Monona on: aluminum leaching
> Resent-Subject: Re: Monona on: aluminum leaching
> ----------------------------Original message----------------------------
> In what form does aluminum leach from pottery, and is this form in any way
> bioavailable? The aluminum would almost certainly never be in elemental
> form, (how hot is a bauxite furnace?) The alumino-silicates that comprise
> fired clay and glazes must be about the most stable way on earth to fix
> aluminum. Even low-fired unglazed earthenware can survive a thousand years
> in the ground without much deterioration.
> I'm extremely dubious. We live in a miasma of aluminum-- it's in the
> ground we walk on, it's in the soil that supports most of the landbased
> life on earth and potters spend their lives with their hands covered with
> the stuff. Human beings probably process several pounds of the stuff
> through their mucous membranes every month, just filtering ordinary dust
> out of the air.
> I'd need some pretty definitive cites before I could take this at all
> seriously. Though I have to say that Monona is absolutely right about the
> potential for well-meant hysteria-- some folks don't require actual facts
> before they get excited, so it's a good idea to get the facts marshalled
> into a great big hammer we can use to squash any attacks on one of the
> essential materials of our art form.
> Ray

You are making the same mistake that Gavin made. Read that post. The
aluminum from the glaze tests is in a soluble form. Don't mix insoluble
aluminum-containing mineral dusts, hot bauxite furnaces, and such, with
aluminum dissolved from the surface of a glaze.