There is a golden lustrous surface quality to much of my work which is almost impossible to capture properly in photographs. It is not an applied glaze or metallic lustre, it is a natural effect of the 1320c reduction wood firing process on my porcelaneous stoneware blend.
"Reduction" gets it's name from the chemical change that occurs when a reactive element like Carbon (C) steals Oxygen (O) atoms from metallic oxides, like Red Iron Oxide (Fe2O3), to make CO2 molecules, thus "Reducing" the amount of Oxygen in proportion to Iron and forming molecules of Black Iron Oxide (Fe3O4) or even further to (FeO), and eventually to the pure metal (Fe).
This is the same process by which metals are smelted.
For the purpose of pottery, this chemical change results in colour reactions like those of Tenmoku and Celadon Iron glazes and Copper Red glazes in reduction firings. But it also causes the golden lustrous surfaces on some Shino glazes, where Iron which is present below the glaze migrates to the surface under heavy reduction. I suspect that this is similar to what is happening in my firing, though there has been no surface treatment, no glazes, no slips, just the Tatami rushes and the wood ash and gaseous fluxes coming into the kiln with the flame from the fire boxes...
Wood firing is capricious and serendipitous, and therein lies its unique and unassuming beauty, variety and charm.
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