On this particular class day, a friend of the instructor came in to help us with a hands-on session of sagger firing. In this case, we had made pots with a burnished finish which were already bisque fired prior to this exercise. In general, sagger firing places each piece in a container where it can sit in an atmosphere relatively isolated from other pieces.

We began (at least most of us) by spraying the pieces with a dilute ferric chloride solution (using appropriate precautions - ferric chloride is used to etch copper laminate to make pinted circuit boards). The light coating promotes a color cast toward the orange side. After that dried, we were able to dip or brush some spotches of a muddy, gritty mixture to produce other colors. Additional organic material to provide reduction was added as the pots were wrapped in aluminum foil. Sphagnum moss wetted with copper sulphate solution, fern leaves and pine needles were among the choices.

The refractory rings of an old electric kiln were used for firing. Small stilts were placed between the rings for combustion air flow. A thick bed of wood shavings was placed in the bottom and a layer of wrapped pots placed on that. A few more wrapped pieces went on top of that layer, then more shavings were added. The shavings were ignited with a propane torch and the smokey fire was allowed to burn until it pretty well died down in an hour or so. While that was going on, a firing was done in the raku kiln.

In addition to the various materials already mentioned, we had on hand some horse hair, feathers and one student brought in a bunch of shed snake skin. For this firing the bulk of the pots were unglazed white raku clay. Rather than placing the red hot pieces in closed metal cans of sawdust, etc. for reduction, these pieces were placed on a metal table and bits of feather, hair or skin applied. On contact the organic material burns leaving a black carbon marking in the clay. The process is fairly random, hair twists and kinks as it burns, and that creates wiggles in the resulting lines.

The sagger fired pieces were dug out and unwrapped. When cool enough to handle they were scrubbed and allowed to dry. Since the burnishing leaves a relatively smooth nearly glossy surface, applying wax and buffing produces a nice luster. We had a fun day (in spite of heavy rain on the kiln deck) and saw many ideas that can be incorporated into future work.