The other day when I was sweeping up the ashes from my fireplace, I paused to look at the benign powdery stuff in my dust pan with wonder. For wasn’t it this ash (which I was in the process of sweeping away) that created those interesting, unreplicable surfaces on the wood fired pots that I so loved? I wondered what result these ashes might yield in a cone 6 oxidation kiln. With that idea in mind, I aborted my cleaning plans, carefully collected the ashes in a container and rushed to my studio. The first thing I needed to do was to clean the ashes, so I passed them through a kitchen sieve to remove the debris. I then mixed the clean powdery residue with water to make a slurry. The consistency of the slurry was more like a thin glaze. It was surprising to see how all those ashes resulted in such a little yield. My experimental ash glaze fit into a little plastic mouthwash cup! Luckily, I had a bisqued tea bowl at hand, ready for testing the ash-water slurry glaze. I sprayed some areas of the tea bowl with a smattering of white slip and the slurry, making sure to vary its thickness around the pot. I loaded t
he experimental piece along with other pots and fired the kiln. The firing and cooling seemed to take an agonizingly long time. But when I finally got my hands on the tea bowl I was intrigued by the results. Areas where the application of ash was thick, it formed wet brown beads and in thin areas it gave the piece a speckled variegated surface, a rather interesting and pleasant result from an oxidation firing. The promising results of the ashes in cone 6 firing has opened up a whole new area of experimentation for me. My next goal is to try a glaze recipe where the most prominent ingredient is ash. In the meantime, my problem is that the weather has become a bit warm to use the indoor fireplace so either I have to find an alternate source of ashes or burn some wood in the backyard for my project. It seems ironic that the ashes that I had so carelessly swept away in the past have become a thing to covet!
Look at you having fun! I love the part right around the rim. Does that change from dark to light have anything to do with the ashes?
Yes Earnie, I am really having a lot of fun! So if you recall, my clay body fired black at cone 6. The darkest edge at the top is where the ash was probably very light and hence the black clay is showing through. As the accumulation of ash increases the colors start to vary becoming more mottled brown. The lower part of the cup is lighter owing to the spray of white slip. The ash that accumulated on that part also has a lighter hue.I can’t wait to do more experiments with this. So if you find a steady source of wood ash please let me know :).