Feux de fosse

Pitfiring

The stoneware pots are burnished with a smooth stone or metal spoon prior to being bisque-fired at low temperature to preserve the shining patina.

 

By rubbing the hard surface against the leather hard clay, the clay particles on the surface become aligned reflecting light, giving a shine to the pot.


Prior to being placed in the pitfire, the pots are sometimes decorated with lithographs, as well as natural oxides (chrome, red iron) and stains to enhance the surface.

 

The burnished pots are then fired in an earth pit, the oldest method of "baking" a pot dating back nearly 30,000 years.

 

I have also experimented with glass frit on slab built bottles, a distant testimony to the first industrial revolution.

 

The spectrum of colours obtained from the oxides and firing conditions is reminiscent of cave art and paintings.


Cave painting of spotted horses and hand prints at Pech Merle (France) 

Photo by Dean Snow 

Footprints cast in resin - Matt Smart

Photo courtesy of the artist

Back of a pitfired platter (2018)



Pitfiring is an atmospheric process where varied colours and patterns can be obtained from items that are placed with the pots, and which turn into vapor and swirl around the pieces in the pit.  Potters build saggars (closed chambers) with crumpled foil or paper around the pots, which have been previously dusted with iron oxide or copper carbonate.  This creates a reduction atmosphere, where oranges, purples, reds, greens and blues develop and mottle the surface of the porous clay.  Sprayed ferric chloride gives intense yellow-orange hues. The choice of fuel (wood, charcoal, sawdust) can also impact on the results. 


  

The air circulation around each pot during the firing will have a key impact on the colouring and give a smoke effect.  A slow and long firing guarantees dramatic results, and intensity of colours. A firing would usually last between 18 and 24 hours.