Dick Lehman Pottery
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In my kiln with a wood-fired pot.


Further Reading:

> READ the complete text of an article I authored about saggar-firing, entitled "Fast Fossils: Carbon-Film Transfer on Saggar-Fired Porcelain," originally published in Ceramics Monthly Magazine, (USA), March 2000 issue.


Capricious control:
  Saggar-Firing

"Saggar" is a term used for any structure which encloses a pot during firing: it could refer to a large lidded pot which encloses a smaller pot. Even an enclosure of stacked bricks with a kiln-shelf "lid" would qualify as a "saggar".

In earlier times when kilns were fired with "dirty-burning" wood or coal, saggars were used to protect the pots from the undesirable residue of the combustion process. With the advent of cleaner-burning fuels, the necessity for saggars diminished.

More recently potters have again begun to use saggars - but in a way exactly opposite their original intent: instead of using saggars to protect pots from an outside atmosphere, potters now utilize saggars to encapsulate pots within a very specialized atmosphere.

My approach to saggar firing is to wrap pots in fresh vegetation and place them in the saggar on their sides, atop a bed of sawdust. I then cover the pot entirely with sawdust and place the lid on the saggar. During the firing, due to the presence of heat and pressure - and due to the relative absence of oxygen — the vegetation turns to "activated charcoal", and in the process, releases a film of carbon.

When everything works just right, the film of carbon penetrates the porous porcelain pot. The images you see on the pots are the result of that "carbon transfer". (Paleontologists have told me that this process is very similar to the fossil-formation process called "Carbonization"..or "Carbon Film Transfer".)

This approach to saggar firing is capricious and rather uncontrollable, and the losses high. As in the production of fossils in nature, all the ubiquitous variables must precisely coincide to create these marvelous saggar fired images. Yet I find that the best results make the pursuit worth the losses.

 

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