Salt Glaze Ceramics

Within the broad field of ceramics, salt-glaze holds a singular place. The result of a reaction between common salt and clay, it gives a unique finish that forms an integral part of the ceramic object itself.

The History

Salt-glaze was first developed in Germany around the 15 th century. Up to the early 20 th century, salt glazing was of prime importance to society as it produced wares that were waterproof, impervious to acidic liquids and strong enough to withstand daily use without readily chipping or breaking. The process was used for everything from mugs and jugs to sewer pipes and chimney pots.

Salting is now redundant as an industrial process. In the late 1950's a number of American studio potters started working with this process and it is now held in high regard among potters and pottery buyers alike.

The Process

These pieces were fired in a 10 cubic feet kiln fired with propane gas over a period of 14 hours. The kiln is fired to a temperature of 1300 degrees centigrade. At the latter stages of the firing, common salt, which is composed of sodium and chlorine, is dampened and wrapped in ‘packets'. These are put into the kiln on a piece of angle iron and dropped in front of the burner flame. The sodium in the salt reacts with the silica in the clay (clay is made predominately of silica and alumina) to form a soda glass – the glaze layer on the surface of the clay. Salt resisting pads are applied to the pots to prevent them sticking to the shelving. This leaves the characteristic marking on the base of the pots and on the rims of the lidded pieces.

The Rationale

Salt glazing achieves qualities of texture, colour and surface that no other technique can give. Each piece is totally unique and a record of the salt and flame movement in a particular firing. In a world of mass production and uniformity, it is a challenging and hugely rewarding process.