Last summer I went to Cambridge Wisconsin for the Clay Games and the huge pottery sale they have there each year.
As always, I never have nearly enough time to see all I want to. This summer was even more special, because I met some of the people in my online pottery guild, the
Etsy Mud Team there! What fun to put faces to names!
One of the potters that was selling his ware at Cambridge had wonderful, earthy pots that begged to be touched. They were barely glazed, and the clay shone through the light glaze. There were the telltale shell impressions on the feet and some rims that told me he stilted with shells in his kiln. It looked like some of the other lovely salt or wood fired ware that I lust after.
Imagine my surprise when he told me his work was fired in a gas kiln similar to mine! It seems he too loves the tactile, minimalist look of wood fired ware, so he set out to mimic it in his kiln. He shared a very simple wood ash glaze recipe with me, and told me how to use the shells. I very much wish I could remember his name so I could credit him here!
I had put his ideas on a back burner, since my summer and fall have been crazy busy. But last week I decided to play a little. I had made some small luncheon plates. I wanted to fire them all, but plates take up sooo much room in the kiln that I kept putting off firing them. I was looking at them, thinking how nice it would if you could stack them in the kiln, when I remembered the shell trick.
Shells, in a high fired kiln, act like something like
kiln wash. They don't stick to the glaze as it melts, but do leave their impressions in the work. They also give off their own natural 'glaze' all around them.
(Look at the feet of the plates to see the ring of glaze where each shell sat. )
So, I stacked the plates using three shells between each plate. On the top plate I laid three shells, so that it, too, would have the shell marks. When I took the plates out of the kiln, I washed off the shells (they soften into mush) and used my dremel tool to get off any of the sharp bits, while leaving as much of the natural pattern as possible. I really love the effect!
I also fired a mixing bowl set with shells as spacers. For this set, however, I used one of the potter's recipes for a simple wood ash glaze, using ashes from the trimmings of my plum and apple trees. I applied it thinly to the inside of the bowl, but more on the rim. The outside I left bare. Since I fire my work to cone 10 (2400 degrees F) and it is fully vitrified, (it is completely non-porous, and stone-like) my pottery is food safe without glaze.
(In Japan, unglazed "nanban" pottery is popular, and is prized for its ability to get better with age. ) So I decided to barely brush the glaze on the inside of the bowls to keep the very natural feeling of the pottery, which I wanted the shells to accent.
I think both the plates and the bowls turned out beautifully! I will definitely be firing with shells more often now!
So far, so good! Though, from a close up look at the photo, the bowl right in the middle has some glaze bubbles, so it is destined to be sent on to mosaic heaven, if the picture is correct. 
As always, I never have nearly enough time to see all I want to. This summer was even more special, because I met some of the people in my online pottery guild, the Etsy Mud Team there! What fun to put faces to names!
(In Japan, unglazed "nanban" pottery is popular, and is prized for its ability to get better with age. ) So I decided to barely brush the glaze on the inside of the bowls to keep the very natural feeling of the pottery, which I wanted the shells to accent.