I discovered this glaze on accident while trying to make a batch of Reitz green. Someone in my studio had mixed black iron with black cobalt oxide.
This glaze has a lovely stony matte finish. If applied very thin on light stoneware it creates a gold tan color. Slightly thicker glaze application yields a black color. A heavier application creates a blue-green color.
Applying this glaze extremely thick somehow creates little pimples that create a rough, not food safe texture, so mix to a specific gravity of 145-155, and dip 1-3 times for the different colors.
This glaze is fairly reliable and seems to appear the same whether its very reduced, lightly reduced, or slightly oxidized.
|Nepheline Syenite (Theoretical)||70|
|Ball Clay (Theoretical)||8|
|Black Iron Oxide||0.5|