What baking soda isn’t good for! Some ceramists use sodium bicarbonate (sodium bicarbonate) – or its little brother sodium carbonate – during the firing process to create a “natural” glaze.
You can add the baking soda in several ways. Some ceramists dissolve the powder in water and spray it into the kiln that way; others mix it with wood or other combustible materials.
The heat in the oven causes the baking soda to evaporate. The vaporized soda particles then travel along on the waves of the flames. Where they come in contact with your workpiece, they fuse with the silica particles in the clay and form a hard glaze. You thus get very erratic, unpredictable patterns, determined by the dancing of the flames. Unpredictable, but oh so beautiful!
