What is the difference between oxidation and reduction firing?
Pottery may be fired in oxidation or reduction. Oxidation firing takes place in air with its 21 % oxygen content while during reduction firing excess fuel is introduced at times to consume the oxygen. The reducing agents present during reduction firing react with the claybody and glaze. The type of firing chosen has a huge impact on the final appearance of the pottery. Many glazes such as copper reds and celadons only work in reduction. Oxidation firing often promotes brighter colored, glossy, and some would say harsh surfaces. Reduction firing promotes warmer clay body color and often softer, more visually textured glazes. Oxidation can be achieved in any type of kiln where the atmosphere is not depleted in oxygen through the combustion process. Electric kilns, for all practical purposes fire in oxidation. Fuel burning kilns may be fired in reduction by making the flame richer at certain times during the firing by adding more fuel, cutting the oxygen to the burners, and mainly by part
