Raku Firing

Raku firing is a unique and ancient Japanese pottery technique that produces distinctive and visually striking results. Here’s a brief overview of the process:

  1. Preparation: Artists create their ceramic pieces using a special type of clay. The pieces are typically hand-formed or thrown on a pottery wheel.
  2. Bisque Firing: The pieces undergo an initial firing in a kiln, called bisque firing. This process hardens the clay but leaves it porous, preparing it for the next steps.
  3. Glazing: After bisque firing, the pieces are glazed with special Raku glazes. These glazes often contain metallic oxides, which contribute to the vibrant and unpredictable colors during the firing process.
  4. Raku Firing: The glazed pieces are then placed in a small, outdoor kiln and heated rapidly to high temperatures (usually around 1800°F or 980°C). Once the desired temperature is reached, the pieces are quickly removed from the kiln while still red-hot.
  5. Reduction: The red-hot ceramics are placed in a container filled with combustible materials such as sawdust, leaves, or paper. The combustibles catch fire, and the container is sealed. The lack of oxygen inside the container leads to a reduced atmosphere, affecting the colors and textures of the glaze.
  6. Cooling: After a short period in the reduction chamber, the pieces are removed and cooled rapidly. The thermal shock and reduction process creates distinctive crackle patterns, metallic lusters, and a range of vibrant colors on the ceramic surface.

Raku firing is known for its unpredictability and the element of controlled chaos in the creative process. The results are often characterized by rich, vibrant hues, metallic effects, and unique surface patterns, making each piece one-of-a-kind.

All of our RAKU workshops are hosted at Perkiomen Valley High School in the Fall and Spring by our high school Ceramics instructor, Mr. Chris Bernholdt.