I started making reduction-fired tableware in autumn 2020 when I joined Cernamic, a ceramic studio based in Stoke Newington, North London. The studio provides members with an invaluable opportunity to regularly experiment with reduction-firing. My reduction-fired work results from sharing knowledge with the two founders, Nam and Susi, and the talented members.
After my first reduction-firing, I became fascinated by the deepness of the clay body and glaze created in the firing process. Since then, I have continued working on reduction-fired tableware and experimenting with different clay bodies in the gas kiln.
Reduction-firing requires a specially designed gas/fuel-fired kiln that restricts incoming airflow. Reduction-firing occurs where the kiln atmosphere has insufficient oxygen for complete combustion (more fuel than air to burn it). This produces carbon monoxide gas at certain high temperatures, which will steal loosely‐bonded oxygen from within clay bodies and glazes. The reaction changes the molecular form of the material and produces colour changes. A fascinating effect is iron speckling in clay bodies. The tiny black dots shown in the clay bodies result from the metallic oxide in the clay reacting to the reduction-firing atmosphere. It achieves entirely different clay surface effects than the oxidation in an electric kiln.
On the day of reduction firing, we need to monitor the kiln’s temperature constantly, controlling the input of gas and airflow to create a suitable kiln atmosphere for reduction firing to happen. Every potter has a different firing schedule regarding the firing. We usually do 6-8 hours of monitored firing with 24 hours of slowly cooling down before the kiln opens. We record the firing temperature throughout the whole firing process.