As someone who loves all things clay, I am fascinated by the many “alternative” methods of firing — those that take place outside of a traditional kiln. One of my favorites is raku. I have tried raku several times, and found it to be a lot of fun—it’s fast-paced, hands-on, and it yields gorgeous yet unpredictable results. Plus, there’s the thrill of handling glowing hot artwork and setting things on fire…safely, of course!
It’s relatively easy to participate in a raku firing with the help of more experienced artists, as I have. However, to become proficient at this technique takes time, dedication, and plenty of trial and error. The artists highlighted in this post are truly masters of this unpredictable technique—able to walk the fine line between control and chaos to create work all their own.
Raku was developed in 16th century Japan and was used primarily to create ceremonial tea bowls. However, traditional Japanese raku and contemporary American raku are not the same thing. American raku, popularized in the 1950s by ceramic artist Paul Soldner, was inspired by the Japanese technique, but with key differences.
In Japanese raku, once pieces are removed from the kiln, they cool off in the open air. This process creates distinctive, earthy color variations. In American raku, once pieces are removed from the kiln, they are quickly placed in a container full of combustible materials and covered with a lid. The combustible materials immediately catch on fire, creating a special “reduction” atmosphere in the closed container.
“Reduction” refers to the reduced oxygen content of this type of firing. Because the container is closed, fresh air cannot reach the fire. Without fresh air, the flames consume all available oxygen, then start to pull oxygen molecules from the clays and glazes. This process creates specific chemical reactions in the clays and glazes, resulting in fascinating colors and patterns that can’t be achieved otherwise.
There are several ways to create a reduction atmosphere (using a gas-fired kiln, for example), but raku is by far the most dramatic. It results in a remarkable range of colors and effects, from richly crackled glazes to shiny, metallic finishes, and from brilliant colors to earthy, smoky hues. Every artist must experiment to find out what results are possible with raku, and which ones they like best—and even with plenty of practice and experience, the raku artist must embrace unpredictability, serendipity, and the occasional broken piece.
Having your precious artwork break during firing is always a risk in ceramics—but even more so in raku. That’s because the rapid temperature changes expose the work to a significant amount of thermal shock. Artists counteract this by using special types of clay that can better withstand this shock. Even still, nothing is guaranteed. Additionally, because raku-ware is fired at a low temperature, it is not considered to be food safe or water tight. Raku-ware is best enjoyed as sculptural or decorative works of art rather than as functional pieces.
The next time you look at the spectacular colors and patterns of a raku piece, imagine the transformation the piece went through. Imagine the artist pulling the glowing hot piece out of a sweltering kiln. Imagine the piece sending sawdust up in flames as it is placed in a metal container. Imagine the rich scent of wood smoke in the air as the artist waits to see what the fire has wrought upon her work. Understanding the process and the dramatic appeal of the technique will help you to enjoy the beauty of raku pieces and the incredible skill of the artists who create them.