Raku clay is a ceramic mixture specially formulated to withstand the rapid temperature changes characteristic of the raku technique. This clay contains a high proportion of grog, which gives it remarkable resistance to thermal shock and significantly reduces the risk of cracking during the abrupt cooling that follows firing. In addition, its thicker texture compared to other clays makes it ideal for parts that do not require fine details but must maintain their structural integrity under extreme conditions.
Raku clay is designed to withstand the stresses generated by the rapid transition from a highly oxidizing to a reducing atmosphere, allowing parts to develop unique finishes such as rough surfaces, crackle and metallic color variations. This ability to withstand abrupt changes without compromising the quality of the piece is fundamental to the creation of authentic raku works.
Interesting Fact
In the traditional raku process, the pieces are removed from the red-hot kiln and placed on combustible materials such as straw or sawdust. The raku clay, due to its resistance to thermal shock, allows these interactions to generate unique patterns of color and texture, making each piece unrepeatable.
Helpful Tip
Be sure to use glazes that are compatible with raku clay, as some glazes do not react well to rapid temperature changes and may flake or lose their adhesion. Pre-test small samples to determine which glazes work best with your specific raku clay, ensuring long-lasting and aesthetically pleasing finishes.
