Raku Process

Raku is an old Japanese firing process for pottery. They mainly used it for cups and pots used in the tea ceremony. In the  l960's the Americans discovered the process and experimented in using it as a decorative art form on various pieces.

As with most pottery there is a first firing called bisque which hardens the clay making it possible to apply glaze or other decorative treatments. With raku, the piece is glazed and fired again.  It is the glaze that produces the colors when exposed to firing. The black is carbon forced into the clay.

The second firing varies in temperature plus or minus 50 to 100 degrees. I fire at 1750-1800 degrees. The pot is allowed to come up to temperature and then it is removed from the kiln to a 'reduction' chamber. The reduction chamber might be a garbage can with materials such as newspaper or straw. When the heated pot is placed into the container with newspaper instant combustion occurs. At this point the container is sealed to reduce the oxygen forcing the carbon into the pot.  

The swirling streaks of color are the result of the flames and variation in temperatures.  Therefore, raku is a somewhat random process.

Raku should be used for decorative purposes only since the pot is porous.  Exposure to UV rays can alter the color  the same as it effects most materials.  Care for raku is simply water and a soft brush to remove dust.

Enjoy your rakuware.

Kath