On Plainsman H443 iron insight-live.com/glossary/85">stoneware in reduction firing. Notice Tin does not work. Also notice that between 7.5 and 10% Zircopax provides as much opacity as does 15% (Zircon is very expensive).
Pages that reference this post in the Digitalfire Reference Library:
Tin Oxide, Zircon, ZrO2, Zircopax, Opacifier, Opacity
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