Lesley Alexander on sun 16 apr 00
This is a repeat of an older email, but one bowl I had tested with yellow,
orange and red De Gussa stains deliberately applied thickly in a design
and covered with a deliberately very thin clear had no detectable leaching
of cadmium. However, this doesn't prove it can't, I guess! Lesley in So.
Calif.
John Baymore on tue 18 apr 00
------------------
=3Cclip=3E
This is a repeat of an older email, but one bowl I had tested with
yellow,
orange and red De Gussa stains deliberately applied thickly in a design
and covered with a deliberately very thin clear had no detectable leaching
of cadmium. However, this doesn't prove it can't, I guess=21
=3Csnip=3E
Lesley,
Thanks for the re-post that says it is POSSIBLE to have this be OK. That
is reassuring that under certain conditions it can be done. Of course we
should know it can...... cause industry has to comply with the same laws,
and they are doing it.
You're absoultely right that it doesn't prove it doesn't leach either.
The point that is most crucial in all of the discussions of leaching that
goes on here on CLAYART (and elsewhere) is that you cannot say that based
on a single (or even a few) particular tested pieces that a certain process
or porcedure will be OK in ALL situations. It is like that really fast
comment made on the end of certain commercials.......... your results may
vary =3Cg=3E.
John H. is working toward getting data together from a WIDE study of
leaching to see if there is any predictability based on molecular formulas
(or anything else). Until such a large well researched study is done, the
best that we can do is TEST suspect glazes.
And even if the data people like John H. accumulate tends to show that the
cadmium does not leach out of the encapsulated stains...... until the FEDs
change the law....... you'll still have to do the testing program if you
use it.
Best,
....................john
John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA
603-654-2752 (s)
800-900-1110 (s)
JBaymore=40compuserve.com
John.Baymore=40GSD-CO.com
=22Earth, Water, and Fire Noborigama Woodfiring Workshop August 18-27,
2000=22
| |
|
