Ingredient Amount
Gerstley borate 6.00
Ferro Frit 3110 77.00
EPK Kaolin 7.00
silica 10.00
Add Amount
Copper Carbonate 3.00


Notes: Very nice and stable in wood/soda. 


All tiles: The tiles were made with Alligator Clay Company “Gumbo” clay body. A 200-gram batch of each glaze was run through an 80-mesh screen, and glaze was applied by pouring. Each tile has an Amaco blue underglaze stripe with white spots on the left, an Amaco yellow underglaze stripe in the middle, and an Amaco white underglaze stripe with a sgraffito leaf on the right.

Each set of three tiles pictured above the respective recipes shows examples of the glaze surface when fired in different kilns:

Left tile: Fired in an electric kiln programmed for cone 1, both cones 1 and 2 fired flat.

Middle tile: Fired in a gas kiln with a reduction atmosphere (heavily reduced from cone 010 to cone 08); cone 1 flat and cone 2 at a 45° angle.

Right tile: Fired in a small, recycled electric kiln that was converted to a wood-burning kiln. A mixture of soda ash and Borax was sprayed into the kiln at the end of the firing. These tiles were at the top of the kiln with cone 1 barely soft on one side, and cone 1 unmoved at the other side (I’m guessing this side fired to cone 01 or close to it). 


Shared by David Scott Smith in the July/August 2022 issue of Pottery Making Illustrated.