Raku Pottery: A Guide to This Dramatic Firing Technique

There are few moments in ceramics quite as thrilling as watching a glowing red pot being lifted from a kiln with long metal tongs, placed into a bin of combustible material, and then engulfed in a rush of flame and smoke. That is raku. It is unpredictable, it is theatrical, and it produces results that no other firing technique can replicate. If you have been potting for a little while and fancy trying something genuinely exciting, this guide will walk you through everything you need to know to get started with raku here in the UK.

A Brief History: From Japan to Your Garden

Raku has a fascinating origin story that stretches back to sixteenth-century Japan. The technique was developed by a tile maker named Chojiro, who worked under the direction of the tea master Sen no Rikyu. Together, they created a style of tea bowl — hand-formed rather than wheel-thrown, simply glazed, and fired at relatively low temperatures — that perfectly embodied the wabi-sabi aesthetic of finding beauty in imperfection and simplicity. The Raku family, who took their name from a seal gifted by the ruler Toyotomi Hideyoshi, have continued making pottery in this tradition in Kyoto for over four hundred years.

What most of us in the West practise today, however, is a rather different beast. American ceramicist Paul Soldner adapted the Japanese process in the 1960s, introducing the post-firing reduction stage — that dramatic business with the bin and the newspaper — that gives Western raku its distinctive smoky, metallic, crackled finish. It is this Western raku tradition that has become enormously popular at workshops and pottery studios across Britain, and it is what we will be focusing on here.

What Makes Raku Different?

To understand raku, it helps to contrast it with conventional pottery firing. When you fire work in a standard electric kiln, the process is slow, controlled, and largely hands-off. You load the kiln, set the programme, and come back the next day. Raku is the opposite of that. It is fast — a small raku kiln can reach temperature in thirty to forty-five minutes — and it demands your full attention throughout. You are not just operating equipment; you are actively participating in the transformation of your work.

The key distinguishing feature of Western raku is what happens after the pot comes out of the kiln. Still glowing orange-hot, the piece is placed into a metal container — an old dustbin, a metal bucket, or a purpose-built reduction chamber — filled with combustible material such as newspaper, wood shavings, or dried leaves. The heat of the pot ignites the material, and you quickly seal the lid. Inside, the fire consumes all available oxygen and the atmosphere becomes heavily reduced. This reduction process does remarkable things to the glaze and to any unglazed clay body: metallic lusters develop on copper-based glazes, and bare clay turns dramatically black from carbon absorption.

The Results: Beautiful, But Unpredictable

This is the part that either excites or alarms beginners, depending on their personality. You genuinely cannot predict exactly what a raku firing will produce. Two pots made from identical clay, decorated with the same glaze, and fired side by side can come out looking completely different. The crackle pattern in the glaze — caused by thermal shock as the hot pot hits the cooler air — will be unique to each piece. The spread of metallic sheen on a copper matte glaze will shift and change depending on where the flame reached and how long reduction lasted. The blackening of unglazed areas depends on how much carbon was available.

For some potters, this lack of control is frustrating. For many others, it is precisely the point. You set up the conditions, make good decisions, and then collaborate with fire, chemistry, and chance. The results are often stunning in ways you could never have planned.

What You Need to Get Started

You do not need an enormous amount of specialist equipment to try raku, but there are some essentials. Here is what you will need:

• A raku kiln: These are typically propane-fired and designed to heat up quickly. You can buy purpose-built raku kilns from UK suppliers such as Potclays, Bath Potters’ Supplies, or CTM Potters’ Supplies. Alternatively, many potters build their own from ceramic fibre (kaowool) and a simple steel frame — plans are widely available online, and building one yourself can be a rewarding project. Expect to pay anywhere from £300 to £900 for a ready-made entry-level model.
• A propane gas burner and regulator: Raku kilns are almost always fired with propane. Make sure your regulator and hose are appropriate for the burner you are using and that all connections are leak-tested before each session. In the UK, always buy from reputable suppliers and check that equipment conforms to relevant British Standards.
• Long-handled tongs: These are specifically designed for lifting hot pots. Do not improvise with barbecue tongs — you need proper kiln tongs that can grip a pot securely at arm’s length. Potclays and other UK ceramics suppliers stock these.
• Heat-resistant gloves and protective clothing: Heavy-duty leather welding gloves are the standard choice. You should also wear natural fibres — wool or cotton — rather than synthetic materials, which can melt or catch fire. A leather apron is a sensible addition.
• Eye protection: Specialist infrared-filtering glasses or goggles protect your eyes when looking into a hot kiln. This is non-negotiable.
• Reduction chambers: Metal bins or buckets with tight-fitting lids work well. Keep several of different sizes so you can match the container to the pot. Old galvanised bins from a hardware shop are perfectly adequate.
• Combustible material: Newspaper is the classic choice. Wood shavings, dried grass, or straw also work well. Avoid anything that produces toxic fumes when burned.
• A fire extinguisher and water bucket: Always have these on hand. Safety first, every time.

Choosing the Right Clay

Not all clays are suitable for raku. The rapid heating and cooling that raku involves creates significant thermal stress, and a clay body that cannot handle it will crack or shatter — sometimes spectacularly, and not in a good way. You need a clay body with good thermal shock resistance, which generally means one with a high grog or sand content. Grog — ground, pre-fired ceramic material — gives the clay body the physical strength to cope with temperature changes.

Many UK suppliers offer clays specifically formulated for raku. Potclays’ Raku Clay and Valentine Clays’ T-Material are both widely used and trusted by British potters. T-Material is particularly well regarded for its resilience and its beautiful response to the carbonisation process — the surface takes on a wonderfully varied dark tone where it has not been glazed. Porcelain can be used for raku but is far less forgiving and is better left until you have some experience under your belt.

Keep your walls relatively even and not too thick — around 6 to 8 millimetres is a reasonable guide. Very thick walls hold more heat unevenly and are more prone to cracking.

Raku Glazes: Where the Magic Happens

Standard earthenware or stoneware glazes are not suitable for raku — they are formulated for different temperatures and firing conditions. Raku glazes are designed to mature at low temperatures, typically between 900°C and 1000°C, and they need to be able to withstand the thermal shock of rapid removal from the kiln.

Copper carbonate and copper oxide are the stars of the raku glaze palette. Under reduction, copper glazes can produce extraordinary metallic effects — flashes of gold, red, and green that shift across the surface like oil on water. These are sometimes called copper matte or copper lustre glazes, and they are the reason so many people fall in love with raku in the first place.

Commercially prepared raku glazes are available from most UK ceramics suppliers, and they are a sensible starting point for beginners. Duncan, Amaco, and various own-brand products from UK suppliers all offer reliable raku glaze ranges. Once you are more confident, mixing your own glazes opens up far more creative possibilities — there are excellent raku glaze recipes in books such as The Complete Guide to Mid-Range Glazes by John Britt, or on ceramics communities like the UK-based Ceramic Arts Network.

The Firing Process, Step by Step

Here is a straightforward overview of a typical Western raku firing session:

1. Prepare your bisque-fired work. Raku is almost always done on bisque-fired (once-fired) pieces. Make sure your pots are completely dry and at room temperature before you begin.
2. Apply your glaze. Raku glazes are typically applied fairly thickly — around 2 to 3 millimetres. You can brush, dip, or pour. Leave the bottom of the piece unglazed so it does not stick to the kiln shelf.
3. Allow the glaze to dry thoroughly. This is important. Placing a piece with wet glaze into a hot kiln can cause the glaze to blister or flake off explosively.
4. Set up your outdoor firing area. Raku must be done outdoors or in an extremely well-ventilated space. You need room to move safely around the kiln and to access your reduction chambers without tripping over anything. Check the wind direction — you do not want smoke blowing into your face throughout the session.
5. Preheat the kiln gently. Bring the kiln up to temperature slowly at first, especially if it is cold outside, to reduce thermal stress on the work.
6. Monitor the temperature. Most raku firings target somewhere between 900°C and 1000°C. You can use a pyrometer, but many experienced raku potters also read the kiln visually — the glaze goes from matte to glossy as it melts, and that transition is a useful indicator.
7. Remove the pots with tongs. This is the moment. Working quickly but calmly, lift the pot from the kiln and carry it to your reduction chamber. Have a helper close the kiln to retain heat
   if another piece is still firing.
8. Place the pot in the reduction chamber. Lower the piece into your container — a metal bin lined with combustible material such as newspaper, straw, or wood shavings works well. The glaze and any unglazed clay body will still be at temperature, and the material will catch immediately. Allow the flames to take hold for a few seconds before placing the lid on the container.
9. Leave it to reduce. Timing here is a matter of experimentation. A short reduction of two or three minutes will produce different results from a longer one of ten or fifteen. The oxygen-starved atmosphere inside the container draws carbon into the clay and glaze, creating the blacks and silvers characteristic of raku. Metallic lustres from copper-based glazes develop during this stage, and the longer the reduction, the more pronounced those effects tend to be.
10. Quench or cool in open air. Once you are satisfied with the reduction time, remove the lid and either allow the piece to cool naturally in the open air or quench it in a bucket of water. Quenching stops the process immediately and can produce additional surface crazing, though it does introduce thermal shock, so it is not suitable for every piece. Handle the pot with tongs until it is cool enough to touch safely.

Throughout the firing process, keep safety firmly in mind. Raku produces intense localised heat and combustion gases. Work outdoors or in a very well-ventilated space, wear heat-resistant gloves and eye protection, and keep a fire extinguisher or bucket of water close at hand. Combustible reduction materials can flare unpredictably when the lid is first removed, so stand clear and approach from the side rather than directly above.

It is also worth noting that raku ware, as produced by this Western reduction method, is not food-safe. The crazing in the glaze surface, which is so visually appealing, creates a network of tiny fissures that can harbour bacteria, and many raku glazes contain metallic compounds that are unsuitable for contact with food or drink. Finished pieces are best treated as decorative objects rather than functional tableware.

Conclusion

Raku is one of the more immediate and physically engaging processes available to a potter working in the UK. It requires relatively modest equipment, tolerates a good deal of improvisation, and rewards attentiveness — both to the kiln and to the material itself. The results are unpredictable in the best sense: no two firings produce identical work, and that variability is not a limitation but the point. Whether you are working on a short course, firing in a shared studio, or setting up a small outdoor kiln at home, the technique is accessible enough to begin with and deep enough to occupy a serious practice for years. The combination of ancient lineage, direct process, and striking visual results makes raku a firing technique that continues to hold a well-earned place in British studio pottery.