John Baymore on sat 2 oct 99
------------------
(clip)
Thank you for posting the results of your glaze tests=21 That should help us
all. Just think, if each of us would have =22one=22 of our glazes tested and
post
to the list, we all would be so much smarter and safer.
(snip)
I think that it is important to remember that testing results involve
numerous variables. The results of one test are only valid for the
conditions that the test piece was made under. These variables are just
that... variable. Such basic things as exact cone fired to, claybody used,
and slips/washes used could possibly have a significant effect on release
figures. The effects of this stuff have not been effectively studied
enough so that we can, with assurance, say that for example a one cone
firing difference has no impact on release figures. What one potter calls
=22cone 6 down=22 another calls =22cone 7=22...... or =22cone 5 1/2=22......=
and so on.
So it is probably ill advised to make conclusions about =22all=22 situations
based on single sample.... particularly without extensive reliable data on
the exact genesis of the tested sample.
The public sharing of this type of data would certainly be a good START to
exploring the dynamics of the problem and pointing to where we might want
to be exploring more. The Janet DeBoos barium research is a great example
of how certain =22assumptions=22 can be proven wrong through a decent piece =
of
research. John Hesselberth is undertaking more along these lines and
should have some good info a ways down the road.
If we use materials that are in the potentially toxic realm, and we put
them on functional ware, we probably need to do our own testing for
leaching to have more meaningful data. The tests are cheap.
Best,
.....................john
John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA
603-654-2752
JBaymore=40compuserve.com
John.Baymore=40GSD-CO.COM
| |
|
