During a visit to Tokyo I attended an exhibition of wood-fired ceramics by famous artists. The pieces were fired over 10 days to cone 10-11 in noborigama kilns using up to 4,000 bundles of red pine wood!
I wondered if I could approximate the beautiful glaze characteristics in a simpler way – by using a gas-fired kiln introducing a suspension of baking soda supplemented with wood ash through multiple spray holes. We built the kiln used parts from old electrical kilns. The firebox is at the bottom left and several spray holes are visible.
Trying noborigama technique with a gas-fired kiln.
A small vase with golden colors.
A long vase with blue coloration.
More details can be found in Ceramics Technical, 2013, vol. 37, "An Alternative to Woodfiring Using Gas at Cone 6" by Minori Thorpe.