This is the sort of thing you can easily do in your own backyard (subject to local council regulations of course). It’s a simple firing technique used in many ancient cultures across the globe and popular with potters today.
Difficulty Level: easy Time Required: half a day
Here’s How:
- Dig a pit of the appropriate size, depending on the amount of work to be fired.
- Place a bed of dry leaves and twigs and possibly coal, which will burn slowly, at the bottom of the pit
- Place the pottery on top of this.
- Carefully sprinkle oxides and carbonates around the pieces (particularly copper carbonate), which volatilize and result in flashes of color appearing on the fired work.
- Cover the work with more leaves, twigs and dung (if available), building up a mound over the pieces.
- Once the stacking process is finished, light the pile around the edges and leave to smolder for several hours, or until the next day.
- Towards the end of the burning process, bury the pit in earth or sand, which will cut off the oxygen supply and create a strong reducing atmosphere inside the mound.
- Allow the kiln to cool overnight and open the next day.
- Remove excess scum with a wire brush under a running tap.
Tips:
- Additions of grog or volcanic ash ‘open up’ the clay and make it more resistant to heat shock.
- The best color results can be achieved with iron bearing, or red clays.
- Bisque firing the work first helps to prevent shattering and cracking.