Hot from the Kiln: Etseri, Svaneti

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Our pottery-teaching guest was planning to use her second week with us to help her school-age pupils paint their work, which they had spent her first week most enthusiastically hand-building and even throwing on her potter’s wheel. But, unfired, it would be so fragile! This is clay at its most delicate, “bone dry” but before the relatively low-temperature bisque, or first, firing has driven off all its chemical water and left it non-soluble in water. I decided to try a small experiment.

I found the broken off handle from someone’s cup, and put it into the oven of our monster Svan stove, then started the stove with wood as usual and let it reach its normal working temperature of about 150 degrees C. Once I had let it burn down, as we do each night, and cool, the next morning showed me a transformed sample. Its color was now much redder instead of the gray it had been. Most importantly, it was now non-water-soluble!

So… the humble Svan stove has found a new use, at least for earthenware, which our clay seems to be, as opposed to stoneware or porcelain, which both need higher temperatures for first and second firings. We checked with the man who sold my guest her clay in Tbilisi, and he said that 12-14 hours at 970-1000 degrees C or so was the temperature for this clay’s necessary second firing. Well beyond what my stove could, or should, put out, not even being insulated. But 150-250 degrees for the first firing, for two or three hours (using my chimney-mounted thermometer)? That we could do!

From then on it was simply a matter of packing the oven as tightly as we safely could, nothing touching each other or the oven walls, firing it up, and keeping it going. We learned that the redder color was an essential guide to a piece’s really being bisqued, and that if it stayed gray it wasn’t ready. A few pieces broke, a couple even exploded, due to uneven wall thickness causing more uneven expansion than the piece’s intrinsic strength could handle, or possibly due to an air pocket needing release as it superheated. But, generally, we were getting proper bisque-fired earthenware, which the children could then color without fear of it dissolving with the water-based paints we had (glazes that you fire on the piece are beyond us at this stage, but hey, one step at a time.)

This was the first time I had ever been in a position even to try firing clay in my own wood-burning stove, so it was most gratifying to see how successful it could be. Now, building a kiln for higher-temperature firings into the 1400s of degrees or so is another matter. It must be well insulated to keep all that heat in and not waste it, using specially made fire-bricks. And will you use electricity, gas or wood to fire it? Each has its advantages and drawbacks. Will the kiln atmosphere be oxidizing, to give your porcelains a good pure white finish, or reducing, which grays them but is fine for stonewares and earthenwares? A whole education in itself.

You then go on to clays, glazes, firing times, special processes such as salt glazes, very slow-cooling crystalline glazes, or the very exciting Japanese-originated Raku method. In this, pieces are removed red-hot from the kiln with tongs, already glazed, and plunged into a bin of combustible material like dry grass, which bursts into flame, then lidded. The quiet ongoing burn deposits metallic salts on the piece’s surface, and it comes our iridescent, gold or silver; but there is quite a higher percentage of losses from breakage due to the suddenness of the temperature changes.

I left behind the world of ceramic art more than 30 years ago when I began travelling the world, but now, suddenly, it has caught up to me in my own home. I wonder what our next step together might be?

Tony Hanmer has lived in Georgia since 1999, in Svaneti since 2007, and been a weekly writer for GT since early 2011. He runs the “Svaneti Renaissance” Facebook group, now with nearly 2000 members, at www.facebook.com/groups/SvanetiRenaissance/

He and his wife also run their own guest house in Etseri:

www.facebook.com/hanmer.house.svaneti

By Tony Hanmer