Smooth your formed pot with a damp sea sponge. The smoother the surface the more receptive your pottery will be to saggar firing. Smooth all over the exterior of your pot
Let your smoothed clay pot dry. It can be placed on a table but not in direct sunlight. Once it is dry it is called greenware. This is the stage before the pottery is fired in the kiln.
Coat the back of a spoon with mineral oil. Spread the mineral oil all over the surface of the pot. Once it dries, add another layer of mineral oil. The mineral oil helps further smooth out the pot's surface to help seal it without glaze.
Place sawdust into the bottom of the saggar, which is comprised of two clay bowls that are 3/8 to 1/2-inch thick. Add equal parts of salt and copper carbonate to the sawdust. Put your smoothed pot inside the bottom of the saggar, which is the bottom bowl.
Drape banana peels over the pot. You can use other organic materials or metals in this project. Different materials will achieve different coloring results.
Invert the second bowl of the saggar over your pot. Be sure your pot fits inside. Place it into your kiln and gradually turn to heat to 1600 to 1700 degrees Fahrenheit. Once you are at that temperature, leave the kiln on for twenty minutes.
Turn off the heat and leave the kiln alone for one hour. Then open the kiln to cool for one hour. Open the saggar once it is completely cooled.