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safety in glazes

updated tue 30 jan 01


will edwards on mon 29 jan 01


A little more info regarding a post on potential changes in results where=

iron, magnesium or most any other oxide or transition metal is in matrix =
of a

The point I was attmepting to convey was that they can alter the effects =
the glaze composition either way. Adding TiO2 might help make the glaze m=
viable where copper to an iron glaze may change that. I would think this =
sense to those who study the technology of such, but may perplex those wh=
don't. So simplicity was my goal, not my final word! =

Defining absolute safety in anything is like a game of chance without ful=
toxicology studies, lab reports for extractable materials and complete co=
over measures and weights. However I didn't expect this to be that deep a=
issue. Here is one example to look at for those who might have a reasonab=
interest in this.

Personally If any of the toxicologist on here are willing, I would like t=
o get
their point of view. I have glazes in several labs right now and will con=
this investment to futher study this area that I have not been able to ge=
information on other wise. I do remember Mr. Hesselberth (I hope I spelle=
that right?) has been the most helpful providing information on his Frogp=
web site. Many thanks to you for such information. It is hard to decipher=
make good choices without someone willing to go that extra step! If inter=
I can deliver you the copies of my lab results but I expect my name and
efforts to be validated in the future for accuracy or reported back to me=
fix. I believe that is a resonable method for procurring near accurate
results. (I wouldn't ever say perfect)
Here is the name of the FDA approved lab I use and my recipes are proprie=
information unless approved by me. However it should expand your options =
your own testing. =

JEM Labratories
400 Lavender Drive
Rome, GA.
Charge is 30.00 per sample set up and 15.00 per metal oxide test. I can g=
this rate down if more people are interested!

Also I am sending glazes to be tested to:

Mary Simmons
Dept of Earth and Planetary Sciences
Northrop Hall
University of New Mexico =

Albuquerque, NM 87131-1116


The deal of a life-time 10.00 dollars per metal oxide test. how can anyon=
pass up a deal like that. I use several resources due to the book I am wo=
on. However I am prone to work with Mary and the lab since she is a clay
person herself.

I sincerely would like to encourage others that are using software withou=
toxicity testing to have extractions done so as not to confuse a hazard a=
nd a
toxin, Accute and Chronic when speaking out professionally on the matter.=

Either someone should share these costs or in the least not inform someon=
e in
regards to toxicity without lab testing for such. (I was made understood =
the glazes posted here were summarized for food surface use in most cases=
) You
can only opinionate the results that supposedly are within limits. Trace
elements and chemicals such as Craig mentioned may not be accute in toxic=
but the mixer will encounter Free Silica in the glaze since all compounds=
making clay and glaze must contain some of each, SiO2 and AL203. (Both ar=
hazards) Wear a mask and latex gloves when handleing these materials anyw=
Or ask a toxicologist what the dangers of free silica are in long term/ch=
use of them are where precautions are not used.

William Edwards
Alchemy 101 - Recipes worked up using MATRIX software and then sent to la=
b for
confirmation gives me peace of mind.

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