Ceramics — Studio Reference 06 methods · 600 – 1320 °C

Firing Methods

Same clay, same glaze — a different kiln returns a different pot. Every firing method is a trade between control and character: electricity executes a program, flame negotiates. This page compares the six methods studio potters actually use, what each demands in skill and equipment, and what it gives back in surface.

The invisible variable: atmosphere
Oxidation

Plenty of oxygen — an electric kiln or an open flame. Combustion stays complete and metal oxides keep their formulated colors: copper stays green, iron stays honey.

Neutral

Fuel and air in balance. A transition state that is hard to hold deliberately — most electric firings sit between neutral and oxidizing by default.

Reduction

Oxygen starved. The flame strips oxygen from the oxides in clay and glaze: copper turns oxblood red, iron turns celadon, stoneware bodies toast and speckle. Fuel kilns only.

01

Electric kiln

Atmosphere: oxidation
Difficulty1/5
Control5/5
Temperature950 – 1260 °C Cone06 – 8 Firing time8 – 12 h + cooling

An insulated chamber heated by resistance elements and run by a digital controller that executes ramps, holds and cool-downs to the degree. The atmosphere stays oxygen-rich and passive, so glazes fire the way they were formulated. The default kiln of the modern studio — and the right first kiln.

Pros
+Programmable ramps and holds — repeatable to the degree
+Safe in an indoor studio with a vent system
+Fires largely unattended on the controller
+Full palette, from low-fire brights to mid-fire stoneware
Cons
No flame effects — reduction is out of reach
Elements and relays wear; old kilns drift
Results can read uniform across a load
Sustained high fire shortens element life
Best forSchools, shared studios, production ware, underglaze color work.
02

Gas kiln

Atmosphere: reduction or oxidation
Difficulty3/5
Control3/5
Temperature1220 – 1300 °C Cone8 – 11 Firing time10 – 16 h, attended

Burners fire into the chamber while a damper meters the exhaust. Close the damper and the oxygen-starved flame pulls oxygen out of the clay and glazes themselves: iron turns celadon, copper turns oxblood, stoneware bodies toast and speckle. The potter manages temperature and atmosphere at once — by eye, cone pack and flame color.

Pros
+The reduction palette: celadon, shino, tenmoku, copper red
+Atmosphere becomes a creative variable
+Toasted body tones and iron speckle for free
+Scales from test kiln to walk-in car kiln
Cons
Outdoor or professionally vented installation, gas plumbing, permits
Damper craft is learned over many firings
Needs attendance for the whole firing
Uneven heat until you know the kiln
Best forStoneware and porcelain with the classic reduction glazes.
03

Wood firing

Atmosphere: reduction + ash
Difficulty5/5
Control2/5
Temperature1260 – 1320 °C Cone9 – 13 Firing time1 – 6 days stoking

A tunnel or catenary kiln stoked by hand, around the clock, for days. Fly ash carried through the chamber melts onto shoulders and rims as natural glaze; the flame path paints flashing across bare clay. Position in the kiln decides the result — a wood kiln is loaded the way a painting is composed.

Pros
+Fly-ash glaze and flashing no bucket glaze can imitate
+Placement in the flame path becomes composition
+Unglazed surfaces carry the full record of the fire
+Days of shared stoking build real community
Cons
Round-the-clock stoking shifts
Cords of split, dry wood per firing
High, uneven loss rate — every load has casualties
Kiln building, rural site, smoke regulations
Best forOne-of-a-kind vessels where the flame does the decorating.
04

Soda & salt

Atmosphere: vapor glazing
Difficulty4/5
Control2/5
Temperature1260 – 1300 °C Cone9 – 11 Firing time12 – 16 h, attended

At top temperature, salt is shoveled into the firebox or a soda-ash solution is sprayed in. The sodium volatilizes and reacts with the silica in the clay surface, growing a glassy sodium-aluminosilicate skin with the signature orange-peel grain. The glaze happens inside the kiln, not in the bucket — interiors still need a liner glaze.

Pros
+Glaze grows on the bare clay — the form stays in front
+Orange-peel texture, orange-to-blue flashing
+Striking on porcelain and light stoneware
+Every load maps the vapor path differently
Cons
Corrosive vapor demands a dedicated kiln
Salt releases acidic fumes — soda burns cleaner
Ware sits on wadding; every foot shows marks
Shelves and kiln furniture wear out fast
Best forThrown forms with crisp profiles that deserve bare clay.
05

Raku

Atmosphere: post-fire reduction
Difficulty3/5
Control2/5
Temperature850 – 1000 °C Cone010 – 06 Firing time30 – 60 min per cycle

Ware is pulled from the kiln glowing at around 900 °C and buried in combustibles — sawdust, newspaper — under a lid. The smoke inks the crackle lines black and the oxygen-starved afterglow flashes copper glazes metallic. Western raku adapts, and departs from, the 450-year-old Japanese Raku tradition built around the tea bowl; the post-fire reduction step is the Western addition.

Pros
+Finished results within the hour, many cycles a day
+Crackle inked black by the smoke
+Copper lusters and metallic flashes
+Small, portable, workshop-friendly kilns
Cons
Porous and crazed — decorative, not food-safe
Thermal shock claims a share of every batch
Open flame and heavy smoke — strictly outdoors
Tongs, gloves and discipline are non-negotiable
Best forSculpture, vessels and unforgettable group workshops.
06

Pit & smoke

Atmosphere: smoke & fume
Difficulty2/5
Control1/5
Temperature600 – 900 °C Cone Firing time6 – 24 h incl. smolder

The pre-kiln original: pots nested in a pit or barrel among sawdust, salts and copper carbonate, then burned and left to smolder. Carbon clouds and fume blushes mark the burnished surfaces directly. Humanity fired clay this way for tens of thousands of years before the first kiln was built.

Pros
+No kiln needed — a pit, fuel and patience
+Burnished and terra-sigillata surfaces glow
+Carbon clouds and fume blushes, never twice the same
+A direct line to the oldest ceramics there are
Cons
Low-fired: fragile, porous, decorative only
Direct flame contact cracks ware
Weather-dependent, smoky, site-hungry
Sealed with wax at best — never food-safe
Best forBurnished handbuilt forms and elemental surfaces.

Temperatures, cones and durations are typical studio values, not physical limits; every kiln, fuel and schedule shifts them.

Fuel-burning and vapor kilns: follow manufacturer instructions, local codes and ventilation requirements, and never leave a fuel kiln unattended.

The trade at the heart of firing
Control is bought with electricity. Character is bought with flame.