Raku describes a Japanese pottery tradition that dates back over 400 years. Specifically, "raku" is used to describe the particular technique that the Japanese used to fire their handcrafted tea bowls (figure 1). Irregular in appearance but pleasing to the eye, the bowls embodied the spiritual ideals of austerity and tranquility. Thus, the tea bowls were prized by Japanese tea masters, and used in special tea ceremonies. The word "raku" may be translated to mean pleasure, happiness, or contentment.

The process is simple. Pottery is placed into a pre-heated kiln (figure 2) where it is quickly raised to full temperature. While still glowing hot, the pieces are removed and allowed to cool (figure 3). This differs from conventional firing techniques where pieces are introduced to a cold kiln, heated in a series of steps, and allowed to cool slowly. A special clay mixture enables the pottery to withstand rapid temperature changes without breaking. The clay mixture and unique firing process yield pottery that is very fragile and porous. Raku pottery is intended for decoration only. Over 400 years, the technique has evolved. While the process is similar, western modifications to the raku approach to include "post-firing," or smoking of the pieces once they've been removed from the kiln.

While still hot, the pieces are placed into a barrel of straw, leaves, or other combustible material. The straw ignites from the heat of the pottery, and the flames exhaust the oxygen in the barrel (figure 4).

Without oxygen, the elements in the glazes are chemically reduced. In some cases, the straw may leave impressions in the glaze creating it's own unique pattern. The resulting colors and patterns are unusual and unpredictable (figure 5).