by Timm Frink - February 2, 2008
Last Sunday I helped set fires in a city parking lot. All in the name of art (craft too). In the name of pure, giddy fun also. No, it was not an exercise in Anarchistic Performance Arson, but instead my third participation in an American-style raku firing.
If you’ve ever had occasion to stop into a local potter’s gallery, you’ve likely seen some examples of raku pottery. The most popular examples are crackle glazes: often a white glaze that is highly crazed, with India ink used to highlight the cracks. You may even own a piece or two. What you may not know is how and why it differs from other pottery.
First things first: American raku is not the same thing as Japanese raku. For the Japanese, raku is far more specific. Actually, it refers to pottery made by the Raku family, mostly for use tea ceremony use. American raku is a derivative: in the raku style, if you will. Derivative of only one method taken from a centuries old tradition, for that matter. The Japanese technique that American raku is based upon was wood-fired and did not include post-firing reduction. More on that later. Suffice to say, we’re discussing American raku here.
So what makes it raku? While there are clay bodies and glazes specifically formulated for raku, it is the technique that sets it apart. The technique is also what makes is such fun. Once the pots are bisque fired and glazed, you fire them again until the glaze fully melts and smoothes out. Or, as my teacher puts it, “Till the glaze looks like sunlight reflecting off a pool of water on the surface of a frozen lake.” The kiln is then opened and the red-hot pots are swiftly removed and placed into reduction chambers. By reduction chamber, I mean metal trash cans filled with straw (or whatever combustible material you prefer) that combusts upon contact with 1800F pots. Once the can is loaded with pots and roaring flames are 
shooting skyward, on goes the lid, tight. This allows the flame to consume all the available oxygen in the chamber, thus turning it into a reducing environment. Reduction plays with the glaze chemistry and traps carbon from organic material in the clay body itself, leaving unglazed clay varying from silvery grey to soot black. Along with the highly crazed crackles, you get, depending on the glaze vibrant greens, spidery veins of copper, black-backed iridescence and a thousand variations in between. Contact with the straw can leave its mark too, resulting in highly textured pieces.
The results from this junction of fire and clay are, if not entirely predictable, often remarkable. At least, when they don’t explode from thermal shock. Though not, technically functional ware (too porous), they are beautiful; a function in its own way. My main joy as a potter remains creating functional stoneware pieces. Still, I find myself already looking forward to the next time I can gather with other potters in a parking lot and toss clay into trash cans.
More pictures - by Sanna-Leena Rautanen
Timmothy Frink is a software developer and transplanted New Englander living in the DC Metro area. He blogs at This Page Intentionally Left Blank.