George Koller on wed 4 feb 04
Hi Folks,
We've been using Zinc Oxide for years and it has always been
WHITE.
Today, while setting up our new powder storage system, I opened
a bag of "Denzox" from Eagle Zinc Company, Hillsboro, IL I noticed=20
a distinct greenish tint. =20
We fire our most common glazes to Cone 04.
What is this about? =20
If Iron Oxide is the offending colorant - will this likely disappear in =
the firing? =20
Should I contact the supplier?=20
Recommendations for another source?
Thanks for any clues,
george koller
sturgeon bay, wi - door county
northport, mi - leelanau county
two great places separated by 100 miles of great lake.
WHC228@AOL.COM on wed 4 feb 04
Time to calcine that Zinc. Put it in some bisk pots and fire it in your
electric kiln to 1256F.
It will turn a yellowish white.
Ivor and Olive Lewis on thu 5 feb 04
Dear George,
Get back to your supplier.
Ask for a full materials data sheet including a true, not
specification, analysis. Ask "Why is this stuff green and not white?"
The only opinion I offer is that it might be coloured with an organic
dye as a means of distinguishing it from other grades of Zinc Oxide.
Best regards,
Ivor Lewis. Redhill, South Australia
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