Ash glazing
Ash glazing is a ceramic glazing technique in which wood ash is used as a primary component of the glaze. The method has been widely used in East Asian ceramics and played an important role in the development of traditional Japanese pottery.
Wood ash contains minerals such as calcium, potassium, and silica that can melt at high temperatures to form a glassy surface on ceramic vessels. Potters may prepare ash glazes by collecting ash from burned wood, washing and sieving it, and mixing it with clay or other glaze ingredients before applying it to the pottery.
In wood-fired kilns, ash glazing can also occur naturally. During long firing cycles, ash carried by the flames settles on the surfaces of the pottery. When the kiln reaches high temperatures, this ash melts and forms natural glaze deposits. These effects are especially characteristic of traditional firing methods such as Wood firing, particularly in anagama kilns.
Ash glazes often produce soft green, brown, or amber tones and can create textured or flowing surfaces depending on how the glaze melts during firing. The results are influenced by many factors, including the composition of the ash, the firing temperature, and the position of the pottery inside the kiln.
Ash glazing has historically been associated with several Japanese ceramic traditions, including Shigaraki ware, Iga ware, Tamba ware, and certain wood-fired works related to Bizen ware.
