Salt glaze pottery has no glaze applied in the usual way. Instead, salt is added to the kiln near peak temperature and the vapor glazes every surface it reaches. The look is unmistakable once you know it: a thin, glossy skin with a dimpled orange-peel texture, usually in grays, browns and cobalt blue.
This guide is written for hobby potters. It covers how salt glazing works, how to recognize salt glazed stoneware, a short history, why it cannot happen in a home electric kiln and how to take part in a salt firing safely. It is research-based, drawn from Ceramic Arts Network, Digitalfire, museum and reference sources and a university safety guide; we did not salt fire pots ourselves.
How salt glazing works
The basic chemistry is simple. When common salt (sodium chloride) hits a very hot kiln, it vaporizes and reacts with water vapor from the flame. Wikipedia gives the reaction as producing sodium oxide and hydrogen chloride. The sodium oxide is a strong flux: it settles on the pots and melts the silica and alumina in the clay surface into a sodium glaze. The hydrogen chloride leaves through the chimney and forms hydrochloric acid when it meets moisture in the air.
The kiln has to be very hot for this to work. Ceramic Arts Network says salt needs temperatures near or above cone 6 (about 2,232°F or 1,222°C) to break down, and Digitalfire says salt and soda firings typically reach about cone 10.
Sources give different temperatures: Wikipedia says salt vaporizes as the kiln reaches about 1,100 to 1,200°C (2,012 to 2,192°F); the CAMEO materials database says the kiln is at about 1,200 to 1,250°C (2,192 to 2,282°F) when salt goes in; Ceramic Arts Network says near or above cone 6; Digitalfire says about cone 10. The firing team at your salt kiln will tell you the cone they fire to.
The salt is usually added in several small charges through ports in the kiln. Potters pull small clay "draw rings" out of the kiln between charges to check how thick the glaze is building, because sodium makes pyrometric cones melt early.
What salt glazed pottery looks like
- Orange-peel texture. The glaze is thin and glossy with small dimples, larger with coarse rock salt than with fine salt, according to Ceramic Arts Network.
- Uneven coverage. Surfaces facing the flow of vapor get more glaze; sheltered areas, the insides of narrow forms and the undersides stay drier.
- Earthy colors. Bare clay fires gray, buff or brown. Iron gives browns, cobalt gives blue and manganese gives purple, per CAMEO.
- Flashing. Slips high in alumina take less glaze and show soft color shifts, which potters prize.
- Crisp detail. Because the glaze is so thin, stamped, carved and incised decoration stays sharp.
How to identify salt glazed pottery
If you are looking at a pot at a sale or in a family collection, check for these signs together, not one alone:
- Look at the surface in raking light. An orange-peel dimple that follows the clay surface is the strongest clue.
- Compare front, back and inside. Glaze that is heavier on one side and thin or missing inside a narrow neck points to vapor glazing rather than dipping.
- Check the foot and pad marks. Pots are set on small wads of refractory clay so the vapor can reach under them. Round scars on the foot are common.
- Look for blue decoration on gray stoneware. Cobalt blue brushwork on a gray body is classic of German, Dutch and early American salt glazed stoneware.
- Feel the weight. Salt glazing is a high-fire stoneware process, so pieces feel dense and ring when tapped.
Glazes that imitate salt firing exist, so for valuable antiques ask a dealer or museum.
Salt glaze stoneware: a short history
Salt glazing began in Germany. Wikipedia places salt glazed stoneware in the Rhineland around 1400 and in the Westerwald towns by the 15th century; CAMEO says it was made as early as the 12th century in Holland and Germany. The technique spread to England in the late 1600s, where John Dwight's Fulham Pottery and later the Lambeth potteries, including Doulton, became major makers.
In America, salt glazed stoneware was the everyday pottery of the 18th and 19th centuries: crocks, jugs and churns, often with cobalt blue birds, flowers or numbers on a gray body. Clean air rules later ended most industrial salt glazing; Wikipedia notes that Doulton's Lambeth factory closed in 1956 and Westerwald production ended in 1983. Studio potters kept it alive, and university programs in the US helped spread it from the 1950s on.
Why you cannot salt glaze in a home electric kiln
Never put salt into a home electric kiln or fire a salt glaze in a garage or basement kiln. Salt vapor attacks kiln elements, bricks, shelves and metal, and the firing releases hydrogen chloride gas, which Florida State University's ceramics safety guide calls highly toxic. Ceramic Arts Network notes that salt firing can also release chlorine. FSU says salt glazing should only be done outdoors, with chimneys tall enough to carry the gas above roof level. Local fire code and your kiln maker's manual set what you may fire at home, and salt is not part of normal electric kiln use.
A salt kiln is a dedicated fuel-burning kiln, gas or wood, built for the purpose. The sodium soaks into its bricks and comes back out in later firings, so the kiln is used only for salt or soda from then on, and its burners and brickwork wear faster than in an ordinary gas kiln, as Digitalfire describes. That is an outdoor, permitted, fire-code-compliant structure, not a hobby appliance. For the general differences between fuel and electric firing, see our gas kiln vs electric kiln comparison.
How hobby potters get salt-fired pots
The realistic way is to join a firing run by people who already have a salt kiln:
- Community studios and art centers with an outdoor kiln yard.
- College and university ceramics programs that offer continuing education or open firings.
- Weekend workshops at craft schools, where you make or bring pots and help load, fire and unload.
- Potters' guilds that run shared atmospheric firings a few times a year.
Firings usually take a full day or more and the kiln team handles the salting, burners and safety. You prepare the pots.
What to ask before the firing
- Which cone the kiln fires to, and which clay bodies they recommend or supply.
- Whether pots should be bisque fired first or go in raw (both are done; ask what this kiln uses).
- Which slips and liner glazes they allow inside pots.
- How they want pots wadded, and whether they provide the wadding.
- Whether you need to stay for the firing and what protective gear they require.
Preparing your pots
Use a high-fire stoneware or porcelain body rated for the kiln's cone; Ceramic Arts Network notes that immature clay bodies do not develop the orange-peel surface. Our stoneware clay guide explains cone ratings. Keep forms open enough for vapor to reach the inside, or plan to line the inside with a glaze the studio approves. Stamp or carve your decoration, since the thin glaze will show every line, and keep a few test pieces to learn how the kiln treats your slips.
Salt firing vs soda firing
Soda firing is the newer cousin. It sprays sodium carbonate or sodium bicarbonate into the kiln instead of salt, so it gives a similar sodium glaze without the chlorine-based gas, releasing carbon dioxide and water vapor instead. Results differ: Ceramic Arts Network describes soda colors as often brighter and coverage as less even. Many studios that once salt fired now soda fire. Soda kilns are still dedicated fuel kilns. Our soda firing guide covers it in detail, and wood fired pottery covers the other main atmospheric firing.
Is salt glazed stoneware food safe?
Do not assume it is. Digitalfire notes that salt glazes are high in sodium and almost always craze, which is a concern for functional ware, and some potters line food surfaces with a fitted liner glaze. Whether a particular pot is suitable depends on the clay, the liner glaze, the firing and testing. Treat antique crocks and jugs of unknown history as decorative unless they have been tested. See our food safe glaze guide.
Safety and fire code
- Only take part in firings run by experienced people in a purpose-built outdoor kiln.
- Stand upwind and out of the fumes when salt is added; FSU's guide says to avoid standing in salt or soda fumes.
- Wear the heat-resistant gloves, eye protection and clothing the studio requires.
- Follow the kiln operator's instructions, local fire code and, for gas kilns, propane or natural gas safety rules. Never build your own burner or salt kiln.
- Clay and wadding dust contain silica: clean up wet and wear a NIOSH-approved respirator when mixing dry wadding or slip materials.
What you need
For a community salt firing you mainly need well-made pots in a high-fire clay, a few test pieces and your own basic tools. Our best clay for pottery guide compares cone 6 and cone 10 stoneware bodies, and the kiln team will supply the kiln, salt and wadding.
Sources: Ceramic Arts Network, Ceramics Monthly Techno File "Salt vs. Soda Firing" (temperature, chlorine and hydrogen chloride, sodium damage, draw rings, textures); Digitalfire glossary entry on salt and soda firing (cone, kiln wear, crazing, liner glazes); Wikipedia entry on salt glaze pottery (chemistry, history, decline); MFA Boston CAMEO entry on salt glaze (temperature, colors, uses); The Pottery Wheel article on salt glazed pottery (topic coverage); Florida State University ceramics health and safety guide (hydrogen chloride, outdoor firing, chimneys). Specs checked October 2026.