I have had several requests for a white glaze. These are tests.
I took Spearmint from “Mastering Cone 6” and reformulated it to use local materials (53% local). I have had great luck with Spearmint and it seems to fit my clays very well so, it was a easy choice to to try it will different colorants before trying an entirely different glaze. I mixed test batches of both and instead of copper carb and rutile, I added 5 zircon, 10 zircon, and 6 rutile. The top tiles are the local material mixes and the bottom tiles are the commercial ingredients. These were fired to about cone 5.5. I’m fairly confident, from looking at the tiles, that I managed to mix up a dip of 5 zircon and 6 rutile from the local and the commercial. It’s a bit frustrating to make mistakes like this.
The local materials seems just a hair less melted than the commercial results. Since the analysis I’m using for the whiting is from an old geology paper it’s quite possible it’s off a bit or the wollostonite may just melt a bit better. On a whole, I’m quite pleased with these results and will be making a larger batch.
