Nancy on tue 9 oct 01
Can someone give me their opinion if this glaze is foodsafe. I am
going to send it off the Alfred but I want to keep working with it until I
hear from them. I use it on top of, and under another glaze. Will that
change the outcome of the test. How long does it take to get a report
back from Alfred. Thanks so much. Nancy
Nephelin Syenite 0.4
EPK 0.1
Flint 0.14
Gertsley Borate 0.1
Lithium Carbonate 0.08
Whiting 0.08
Titanium dioxide 0.1
total 100
Copper Carbonate 0.015
John Hesselberth on tue 9 oct 01
on 10/9/01 6:03 AM, Nancy at njervey@SOMTEL.COM wrote:
> Can someone give me their opinion if this glaze is foodsafe. I am
> going to send it off the Alfred but I want to keep working with it until I
> hear from them. I use it on top of, and under another glaze. Will that
> change the outcome of the test. How long does it take to get a report
> back from Alfred. Thanks so much. Nancy
>
> Nephelin Syenite 0.4
> EPK 0.1
> Flint 0.14
> Gertsley Borate 0.1
> Lithium Carbonate 0.08
> Whiting 0.08
> Titanium dioxide 0.1
> total 100
>
> Copper Carbonate 0.015
Hi Nancy,
You didn't tell us what temperature you are firing to so I can't predict
whether or not your glaze will melt. Melting affects stability. From a
composition standpoint it is low on silica (2.2) so it won't be very
durable. It will leach some lithium and copper. Can't guess how much.
Testing at Alfred usually takes 2-3 weeks. I don't have a recent fix on
their service level because I've quit using them. I get much better service
from Brandywine Science Center. I've always gotten results there in less
than a week after they get my sample and usually in 3 or so days.
Regards, John
Web site: http://www.frogpondpottery.com Email: john@frogpondpottery.com
"The life so short, the craft so long to learn." Chaucer's translation of
Hippocrates, 5th cent. B.C.
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