The KPA glaze database is a collection of glaze recipes submitted by members of the association, visitors, demonstrators at our master-days, and other potters from around the world who have visited our web site.
Low Temp. and Raku
Below 1000° - the clay will remain porous and able to absorb smoke
1000° to 1150° - The clay is still quite porous and the ware relies on the glaze to ensure it is waterproof
1150° to 1250° - The clay is close to vitrification, but can still admit some water. Firing is more economical than at higher temperatures
Stoneware and Porcelain
1250° and above - The clay is completely vitrified and will be waterproof even if unglazed
Please remember that glaze materials are variable, so be sure to take the usual precautions when using a glaze for the first time. (Protecting kiln shelves etc.) Also be aware of the toxicity of certain glaze materials, both in the raw state, and in the fired glaze. Any glaze to be used on domestic ware should always be checked for suitability, and in particular glazes containing lead in any form should be tested for metal release by a reputable laboratory.