Anagama: Inside Japan's Oldest Wood-Fired Kiln

An anagama is a single-chamber kiln built by digging into a hillside. Fuelled by wood, it lets flame and ash act directly on the pieces, producing one-of-a-kind scenery such as yohen and natural ash glaze.

It arrived from the Korean peninsula around the 5th century and lifted Japanese ceramics from earthenware to stoneware. Every one of Six Ancient Kilns began with this kiln.

There are no partitions inside; the flame passes straight from the firemouth to the chimney at the far end. That simple structure changes a piece's expression dramatically according to where it stands.

Anagama against noborigama

The evolution of the anagama is the noborigama. For a fuller comparison see our guide to Japanese wood kilns.

Going into the kiln with no glaze

Much of the Bizen and Shigaraki fired in an anagama goes in as raw clay, with no manufactured glaze applied beforehand.

That it still comes out with distinctive color and sheen is thanks to natural ash glaze. Over days of burning wood, a great quantity of ash rises inside the kiln. It settles on the work, and above 1,200°C it reacts with the feldspar and silica in the clay, melts, and turns into a natural glassy layer.

Position decides everything. Near the firemouth a piece takes a thick coat of ash; deep in the kiln, only a little. Upward faces gather ash, downward faces do not. Makers spend days packing a kiln for exactly this reason.

Why the risk of failure is high

• The flame is extremely hard to control　Wind direction, humidity and the state of the wood change the temperature and the flame path inside the kiln second by second.
• The risk of being buried in ash　Wood is thrown in continuously, so pieces near the firemouth end up completely buried in embers and ash. Sometimes that becomes exquisite scorching; sometimes it warps or cracks the work.
• Long physical labour　A single firing means stoking around the clock for several days, sometimes more than a week.

After a battle fought in heat and sleeplessness, it is not unusual to open the kiln and find more than half unsaleable. It is precisely because it is a serious contest with fire that this particular beauty appears.

Related terms and guides

Related terms

• Noborigama: The Climbing Kiln, Chamber by Chamber
• Shizen-yu: Natural Ash Glaze Explained
• Bidoro: The Glass-Green Drips on Bizen Pottery
• Yakishime: Unglazed Pottery Fired to Its Limit
• Hidasuki: The Red Straw Marks on Bizen Pottery
• Japanese Pottery Glossary | Terms, Techniques & Kilns

Read further

• Anagama vs Noborigama: Japanese Wood Kilns Compared
• Japan's Six Ancient Kilns: All 6 Regions Compared
• Yohen: When the Kiln Decides the Colour
• Bizen Ware: Pottery With No Glaze at All

Pieces available at Nokaze

• Bizen Pottery | Unglazed Japanese Stoneware from Okayama