The Origin of Raku
Raku is a firing technique for pottery whose origins are linked to the ancient Japanese art of tea ceremony. This technique is deeply rooted in the Zen philosophy and related to the influence that Buddhism had in the Japanese culture, whose Raku ceramics production can be traced back to the XVI century.
It seems that this technique was created by chance, by a craftman named Chojiro. In order to make pottery that seemed old and worn out in a quick way, he used the same materials and technique that were used for roof tile production – that is, sandy clays – and removed the pottery from the kiln as soon as the glaze had reached the red-heat stage. The thermic shock provoked by the cooling process gave the pottery an aged look, that also added some value to the objects.
The most amazing thing when making Raku pottery is the moment of removing each piece of work from the kiln when it is still bright red hot. Creativity and improvisation, together with a knowledge of different materials, give way to some unique and surprising objects.
All production phases require a totally manual intervention, from initial shaping of the pieces to the preparation and application of glazes to cooking.
After modeling the pieces and letting them naturally dry, a first cooking phase is carried out to obtain the “biscuit”. The pieces are then glazed and cooked for a second time. The peculiarity of raku technique lies in the second cooking phase, which takes place in a special kiln at around 900-1000°C (1652-1832°F) temperature.
The incandescent pieces are then taken out of the kiln and laid down in an airtight container full of naturally combustible material (dried leaves, fir-wood natural sawdust, raw paper). The contact of this material with the incandescent pieces causes a combustion and a subsequent production of smoke. Then the pieces are covered with a metal lid to create a reducing, that is, an oxygen-free atmosphere which is essential to obtain the typical raku colors and effects.
This so called “reduction” phase, combined with the thermal shock, provokes various changes in the pieces. One of the most common ones is the craquelé effect, that is, the presence of more or less profound cracks on the glaze.
This process creates unique pieces. In particular, the final complex cooking phase rarely allows for certain and homogeneous results.
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