Cathi Jefferson on Salt-Firing writes:
“Each piece of my pottery is fired to high – temperature stoneware (cone 10 / 2400 degrees F or 1300 degrees Celcius in a 40 cubic foot gas car kiln.Prior to firing, each piece is dipped with a watery slip then most of the interiors are glazed by dipping with a variety of individually made glazes (usually a Shino glaze).
Some pieces have the watery slip or glaze sprayed on the inside and/or outer surfaces. The exterior surfaces have a variety of metal oxides and terra sigillatas (no glazes) that produces a colour range in the hues of nature. The crispness in colours and varying surface textures are produced by the salt-firing.
Late in the gas firing, I roll up “burritoes” made of salt and baking soda and wood shavings and put them in to the kiln by dropping them in to the kiln on a piece of angle iron. Once in the kiln, they volitize sending salt vapour moving with the gas flame among the pieces of pottery.
The resulting outside surfaces vary from side to side due to the direction of the flame with the salt vapour interacting with the pieces as the flame weaves through the kiln.
Each piece is different and sparkles with a vitality that only the salt-firing process can produce”.
You can see more of Cathi’s fabulous work at www.sidestreetstudio.com A World Made By Hand