Images Copyright © 2018 Sumi von Dassow
The process of pit-firing is one of active collaboration with the elements of earth, wind, and fire. Once the wood is actively burning the pit is covered to retain its heat, while I watch the wind and direct an adequate air supply into the pit to avoid smothering the fire. At a high altitude the air has less oxygen, so it can be challenging to reach the 1400 degrees needed for the development of good color. The use of aspen and its cousins poplar and cottonwood is critical to achieving the desired temperature. Though the fast and hot fire tests pottery to the limit of its tolerance and contributes to a high breakage rate, the successful pots make the loss rate worthwhile. The warm reds and yellows that result from my collaboration with fire and air make each pot seem to embody the colors of autumn, a fitting reminder of the fallen limbs which helped create it.
Pit-fired pottery is unglazed and should not be used to hold water.
For more about pit firing, read my book Low-Firing
Saggar Firing is a related technique in which pots are fired in a kiln, inside an enclosed container called a saggar, with many of the same materials as are used in pit firing.