Almost final recipe for cone 6 copper blue - G2806B

Wednesday 29th July 2015

This is the winner of a five-way cone 6 copper blue glaze comparison that started with my dissatisfaction with Panama blue. When I compared these glazes I did not just eyeball them on a tile. I compared the melt flow, thermal expansion and slurry performance of the bases (without the copper and tin). Ball-melt GBMF tests also showed bubble and color development for very thick sections. Then I tried more copper and did more flow tests. I also did leaching tests. Where needed I adjusted recipes to increase clay content (while maintaining chemistry) so the slurries would work better. Without my account at to keep all of this organized it would have been so much more difficult, actually, I probably would not even have bothered with the project. The final recipe, G3806C, was an adjustment to reduce the thermal expansion of this one.

Pages that reference this post in the Digitalfire Reference Database:

Copper Carbonate, G3806C - Cone 6 Clear Fluid-Melt Clear Base Glaze

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