The raku firing process began in Japan about 400 years ago. The Japanese use wood, we use propane! In this process pots are taken from a red hot kiln (about 1850 degrees) and placed in a container with combustible material. I use a trash can with sawdust and newspaper. Once the lid is placed on the can a reduction chamber is created and all of the available oxygen molecules in the atmosphere, clay and glazes are used to create combustion. Therefore the carbon left in the atmosphere seeps into the unglazed areas on the pot turning the clay black. The raku process if affected by many variables – the type of combustible materials used and the temperature and wind conditions on the day of the firing to name a few. One thing is for sure the effects are spontaneous, immediate and never the same!
I use three raku glazes - one is a traditional white crackle on which I apply color after the firing. The other two glazes contain metallic oxides and the glazes themselves produce the wonderful copper effects during the firing. |