About the Raku Firing Process

Raku was originally developed in 16th century Japan. Fired ceramics were pulled from the kiln and rapidly cooled in water. The aesthetics was prized for use in tea ceremonies.

In the 1960's as raku was being demonstrated in the United States, a reduction process was introduced. Fired ceramics were pulled from the kiln and placed in combustible materials causing flames producing a reduction atmosphere. Effects were then "frozen" by rapid cooling in water. The cracking, smoking and glaze effects produced is the version of raku that is widely sought after today.

In my ceramics, I mainly use a clear glaze with copper carbonate and iron oxide as colorants. I kiln the ceramics to about 1200-1500 degrees F° to where the glaze melts. I then pull the pieces out of the kiln red hot and put them into a metal container filled with eucalyptus leaves. I let them flame up and then cover the container to smoke for a few minutes before dousing with water to cool.

raku firing
After glaze has melted in firing, the red hot ceramic is removed from the kiln. Rapid cooling causes the glaze to harden and crackle.
raku firing combustion
The ceramic is placed in a metal container filled with dry leaves. The heat causes the leaves to combust. Leaves are allowed to burn for a moment, then a lid is placed over the container cutting off the oxygen supply.
raku firing cooling
After a few minutes, the lid is removed and the ceramic is doused with water to immediately cool it.
final ceramic
Finished piece showing where smoke has penetrated the unglazed bottom, crackle in the glaze and inside reduction effects where copper carbonate and iron oxide was added.
Night is the time to fire! After the glaze has melted, the kiln lid is removed, revealing a red hot ceramic platter ready to go.
Metal tongs are used to lift the platter out of the kiln.
The platter is placed into a pit filled with dry leaves where it is allowed to burn for a minute before a lid is placed over the pit to allow the ceramic glaze to reduce and absorb smoke.

Day photos by Linda, night photos by Alana.

© 2002- Perry Okimoto. All rights reserved.