Raku is a distinctive ceramic firing process in which pieces are removed from the kiln while still glowing hot and cooled rapidly, often in containers of combustible material. The dramatic thermal shock and the smoke produced create unpredictable, striking effects – crackled glazes, smoky greys and lustrous metallic sheens. The technique originated in sixteenth-century Japan, associated with the tea ceremony.
Western raku, developed in the twentieth century, has become hugely popular with contemporary ceramicists for the beauty and unpredictability of its results.
How raku firing works
Bisque-fired and glazed pieces are placed in a kiln and heated rapidly, usually to around 1000 degrees Celsius. Once the glaze has melted and matured, the pieces are removed from the kiln while still red-hot using long tongs.
In Western raku, the hot pieces are then placed into containers filled with combustible material such as sawdust, paper or leaves, which ignite on contact. The container is sealed, starving the fire of oxygen. This ‘reduction’ atmosphere pulls oxygen from the glaze and clay, producing metallic lustres, deep crackle patterns and the smoky blackening of any unglazed areas.
What makes raku distinctive
Raku is defined by its drama and its unpredictability. The rapid cooling causes the glaze to craze into a fine network of cracks, which the smoke then darkens, producing the characteristic crackle effect. Unglazed clay turns smoky black, and certain glazes develop iridescent metallic surfaces impossible to achieve by other means.
No two raku pieces are ever quite the same. The element of chance is fundamental to the technique – makers can guide the process but never fully control it, which is a large part of raku’s enduring appeal.
Collecting raku ceramics
Raku pieces are prized for their unique surfaces – the crackle, the smoke, the lustre. It is worth noting that traditional raku is porous and not generally suited to functional use; most raku is decorative or sculptural. Each piece is one of a kind.
At Byard Art, where raku work is available, each piece is presented as a unique example of this dramatic and beautiful technique.
