The Raku Firing Process
Raku is a centuries old firing technique developed by the Japanese. The pieces of pottery are fired outdoors in a kiln fuelled by wood or propane. The pieces are heated very quickly to the red hot stage and while the glaze is still molten, they are pulled out of the kiln and into the air. The iridescent colours and/or crackle surfaces are a result of the chemical reaction of the glaze materials oxidizing when the pots are removed from the kiln.
To stop the oxidation process and control the surface effects and colours, the pots are then placed in a pit or a container, covered with combustible materials and sealed airtight with a lid. This is called a reduction atmosphere. This reduction of oxygen stops the flaming and produces smoke which permeates the clay body and the glazed surfaces.
Raku pieces are characterized by the black, smoked clay body and the unusual spontaneous surface effects. Raku fired pieces are unique and make distinctive decorative objects.