Patsy's Green
Here is another pot from Linda McFarling's Clay Club Experimental, Gail Nichol's style soda firing:
Patsy's Green cone 10 soda fired
46.2% F-4 Feldspar
19.8% Silica
8.3% Whiting
2.4% Kaolin
5.9% Dolomite
13.4% Gerstley borate
4.0% Zinc Oxide
Add:
4.0% Black Copper Oxide
2.0% Bentonite
John Britt
www.johnbrittpottery.com/wks.htm
http://penlandpottery.com/pages/home.php
http://ncclayclub.blogspot.com/
Comments
Actually, it is on a Helmer Body I got from the Helmer Clay Co. in the mail.
John Britt
www.johnbrittpottery.com/wks.htm
Helmar is a kaolin and I have not tested the glaze for copper release, but would probably reduce the amount of coppper as it is in the oxide form which is about 1.4 times a strong as the carbonate form. 5% is usually the limit before it starts releasing a lot of copper. But I would test it before using it on functional surfaces. Of course, you know that from using Willie Hillux!?
John Britt
www.johnbrittpottery.com/wks.htm