Salt-glazed pottery has been a part of ceramic traditions for centuries. It’s a unique method of making pottery using a special firing process. During the firing, salt is thrown into a very hot kiln. The salt turns into vapour and reacts with the clay, creating a glassy surface on the pots. This reaction makes the pottery waterproof and very durable.

The process works because of a chemical reaction. The sodium in the salt combines with silica in the clay to form a glaze. This happens at very high temperatures, usually around 1200°C.

How to Identify Salt-Glazed Pottery

Salt-glazed pots have several distinctive features:

Texture: The surface often looks and feels like orange peel. It’s slightly bumpy or pitted to the touch. Some potters call this texture “tiger skin”.
Colour: Most traditional salt-glazed pots are earthy colours like brown, and grey. These colours come from the clay used to make the pots. Modern potters can create other colours by adding different minerals to the clay or using special glazes under the salt glaze.
Uniqueness: No two pieces of salt-glazed pottery are exactly the same. The way the salt vapour moves in the kiln makes each pot different. Some areas might be shinier, others more matte.
Marks: Sometimes you can see small dimples or marks where the pots touched the kiln shelves. These are called “wadding marks”.
Feel: Salt-glazed pottery often feels very smooth and pleasant to touch, despite its textured appearance.

The History of Salt-Glazed Pottery

Salt glazing started in Germany in the 1400s. It quickly spread across Europe because it was a practical way to make waterproof containers. Different areas became known for their own styles:

German pots were often reddish-brown due to the local clay.
Dutch pots were usually grey with blue decorations painted on them.
English potters, especially in Staffordshire, made famous brown salt-glazed pieces.

Salt-glazed pottery was used to make lots of everyday items like jugs, bottles, and storage jars. It was popular because it was strong and didn’t leak.

In the 1800s, salt-glazed sewer pipes became common. This shows how tough and waterproof salt-glazed ceramics can be.

How Salt-Glazed Pottery is Made

The process of creating salt-glazed pottery is a fascinating blend of art and science. It involves several key stages, each crucial to the final result.

Clay Preparation

It all starts with selecting the right clay. Potters choose clay bodies with a high silica content, as this is essential for the salt-glazing reaction. Often, they mix different types of clay to achieve the ideal composition. Some potters add extra silica or other materials to enhance the glazing effect. The clay must be thoroughly wedged to remove air bubbles and ensure consistency.

Shaping the Clay

Once the clay is prepared, potters shape it into the desired forms. This can be done using various techniques. Throwing on a pottery wheel is common for round shapes like bowls and vases. Hand-building techniques such as coiling or slab building are used for more irregular shapes or sculptural pieces. Some potters use moulds, especially for producing multiple identical items.

Drying Process

After shaping, the pottery must dry completely. This stage can take several days, depending on the size and thickness of the pieces. Proper drying is crucial to prevent cracking during firing. Potters often use controlled environments to ensure even drying.

Loading the Kiln

Once dry, the pots are carefully arranged in the kiln. This step requires skill and experience. Potters use special supports called “wadding” – small balls of refractory material placed between the pots and shelves. Wadding prevents the pots from sticking to the shelves during firing, as the salt glaze can act as a powerful adhesive.

Firing the Kiln

The firing process is where the magic happens. The kiln is gradually heated to around 1200°C (2192°F). This temperature rise must be carefully controlled to avoid thermal shock to the pottery. The heating process alone can take many hours, sometimes a full day or more.

Salting Process

When the kiln reaches the right temperature, usually between 1200°C and 1300°C, salt is introduced. Potters throw rock salt or damp salt into the kiln through small ports. The salt immediately vaporizes in the intense heat. Some potters add salt multiple times during the firing to build up the glaze. The amount of salt used can vary greatly, typically ranging from 0.5 to 1.5 kg per cubic meter of kiln space.

Cooling Down

After the salting is complete, the kiln is allowed to cool slowly. This cooling process is crucial and can take several days for large kilns. Cooling too quickly can cause the pottery to crack. During this time, the glaze continues to develop its characteristic texture.

The entire process, from preparing the clay to unloading the cooled kiln, can take anywhere from a couple of days to over a week. The duration depends on factors like the size of the kiln, the thickness of the pottery, and the specific firing schedule used by the potter. Each firing is unique, influenced by variables such as atmospheric conditions and the placement of pots within the kiln, contributing to the individual character of each piece of salt-glazed pottery.

Types of Kilns Used for Salt Glazing

Different types of kilns can be used for salt glazing, each offering unique characteristics. Wood-fired kilns, which are traditional, can create interesting effects from the wood ash mixing with the salt glaze.

Many modern potters prefer gas kilns because they’re easier to control, allowing for more consistent results. Oil-fired kilns were common in the past for salt glazing, but they’re less used today due to practical and environmental considerations.

It’s worth noting that electric kilns aren’t suitable for salt glazing because the salt vapour would damage the electrical elements. The choice of kiln can significantly influence the final appearance of the pottery, with each type imparting its own subtle effects on the glaze.

Types of Salt-Glazed Pottery

You can find many types of salt-glazed items:

Functional pieces: Mugs, plates, bowls, teapots, and storage jars.
Decorative items: Vases, sculptures, and ornamental pieces.
Architectural elements: Tiles and building decorations.
Historical items: Antique bottles, jugs, and crocks.

Using and Caring for Salt-Glazed Pottery

Salt-glazed pots are known for their durability and ease of maintenance. These pieces are safe for use with food and drink, making them practical for everyday use. While you can put them in the dishwasher, hand washing is generally gentler and can help preserve the pottery’s unique surface texture.

One of the advantages of salt-glazed pottery is its resistance to chipping and scratching, which contributes to its longevity. However, avoiding exposing the pieces to sudden temperature changes is important, as this could cause cracking.

For general cleaning, a gentle wash with soap and water is usually sufficient, but if a piece becomes particularly dirty, you can carefully scrub it with a soft brush without damaging the glaze. With proper care, salt-glazed pottery can remain beautiful and functional for many years

Collecting Salt Glazed Pottery

Many people enjoy collecting salt-glazed pottery. If you’re interested in collecting, here are some tips:

Learn to recognise the signs of salt-glazed pottery.
Look for pieces in good condition without cracks or chips.
Consider collecting from a specific time period or region.
Antique salt-glazed pottery can be valuable, but make sure to buy from reputable sources.
Modern salt-glazed pieces can also be collectable, especially from well-known potters.

Why People Choose Salt-Glazed Pottery

Salt-glazed pottery remains popular for several reasons:

It’s very strong and long-lasting.
The special surface texture is appealing to many people.
It connects us to centuries of pottery tradition.
Salt-glazed pieces work well for everyday use.
Many people appreciate the skill involved in creating these pieces.

Most importantly, each salt-glazed pot is unique. The unpredictable nature of the salt vapour in the kiln means that no two pieces are ever exactly alike. This uniqueness is part of what makes salt-glazed pottery special to many people.

If you’re interested in exploring salt-glazed pottery for yourself, Pots to Inspire stocks a range of these unique pieces. We encourage you to browse our pots collection or get in touch if you have any questions about incorporating salt-glazed pottery into your home or collection.