Expand Your Ceramic Glaze Palette, Part II Lou Roess

On Monday, we presented a couple of ways that you can expand your glaze palette without purchasing new materials or experimenting with new glaze recipes.

As promised, today, Lou Roess shares another handy tip for getting a lot more information out of the glazes you already have. You may discover something new and interesting right in your own studio!—Sherman Hall, Ceramic Arts Daily

A great way to get more colors and textures out of your current glazes is to apply different glazes over or under one another. The best way to check out how your glazes will look when applied this way is to make a test grid. Roll out a square slab of clay (fairly thick—say 1/2 an inch). Make it large enough to allow for 1 inch in length and width for each glaze you want to test. For example, if you have eight glazes, make your slab 8X8 inches. Now, measure out a row with a 1-inch-wide ruler, rolling the edge of the ruler onto the clay to make a line. Repeat for the next row and so on. Make the columns in the same way.

Next, use a stamp to make a design in each individual square or drag a small fork in a wavy line across the width of each 1-inch square. After firing, this will show you how the glaze combinations break over texture. Mark out an equivalent grid on paper to record your entries; it doesn’t have to be to scale.

Since you want this test to reflect as closely as possible what your glazes will do on your work, treat the slab like you do your work; If you bisque fire your work, bisque fire the slab. Begin by brushing your first glaze in a horizontal line from left to right across the top row of the grid. Record this glaze on your paper grid. Brush the second glaze across the next horizontal stripe and record it on your paper grid. Continue brushing different glazes, one to each row, until all rows are covered.

When the last glaze is dry, start on the left and glaze the vertical columns in the same order you applied glaze to the horizontal rows. For example, if you started with white horizontally, start with white vertically. Brush the second glaze vertically in the next column, and so on, until you’ve applied all the glazes. Again, make sure to record your glazes on the paper grid.

Fire the grid, preferably in a kiln load of your usual work, and mount it on a piece of cardboard. It’s a good idea to write the glazes in the order used on the back of the cardboard, then attach the finished grid to your studio wall so it’s handy for reference.

You will now have a good idea of how each glaze looks both over and under all the other glazes. The vertical stripes will be “over” and the horizontal stripes “under." While this flat method doesn’t tell you how the glazes move on a vertical surface, it does uncover colors and textures of interest that you can test further.