The texture and color of cone 06 glazes depend on three variables: selection of the proper glazes, learning the correct way to layer and combine glazes by dipping, pouring, and spraying; and using controlled cooling cycles in electric kilns to enhance the texture and color. The slow cooling process not only creates an interesting visual dialogue in thin and thick areas of glaze application, it also helps certain materials to crystallize, which adds interest and depth to the glaze. With so many cone 06 glazes available, how can you know which glazes will work best for you? I personally like glazes which have a strong calcium presence, of wollastonite, whiting, or dolomite in the formula. These materials form small suspended crystals in the glaze when it is cooled in a controlled fashion. I also like to dip or spray glazes over one another, since no single glaze provides as visually interesting a surface. My technique of layering permits the different glaze materials to melt and combine in unique ways, providing a deep and visually interesting surface. Also, applying glazes over textured clay lets the melted glaze pool, which creates different areas of color on these parts of the surface. The best teacher of what works best for you is trial and error. For example, if you dip glaze X over glaze Y in one kiln silver clay piece, do another piece dipping glaze Y over glaze X to see the difference.
Most glazes have firing ranges of several cones. I fire cone 06 glazes to cone 07 with a programmable controller which governs the heating and cooling cycle. This provides a superior melt, and allows mingling of the many glaze layers. Everyone must experiment and test their glazes to determine the best range for the effects they are trying to achieve. Don't forget to use kiln wash, and place your ware on stilts. It's a good idea to program a hold during the programmed firing if you have a single-zone kiln and want to even out the firing of the piece from bottom to top. Newer kilns have multiple zone programmable controls, which makes a soak at the end unnecessary. If your kiln isn't computer controlled, you can use the infinite switches to fire the kiln down. Adding a pyrometer and a good thermocouple allows you to achieve a controlled cooling cycle. Be sure to follow the manufacturer's instructions for kiln ventilation. It is necessary to keep accurate records, so that when you obtain pleasing results you are able to repeat them. It is much easier to repeat results in electric kilns than in fuel-burning kilns, particularly if the kiln has a programmable controller. It takes much time and persistence in order to achieve surfaces that are pleasing and unique. No single glaze or method can do this. It requires a combination of glazes and types of application, followed by carefully controlled firing and controlled cooling. There is no substitute for experimentation.
