How to Care for Japanese Ceramics: A Practical Guide

Japanese Ceramics Deepen the More You Use Them

There is a rice bowl my grandmother kept using with care. A small chip on the rim, and inside, the faint stain of years of tea. Even so — or rather, precisely because of it — that bowl is beautiful.

Japanese ceramics carry the idea of a piece for a lifetime. Mass-produced tableware is treated as a consumable, but handmade earthenware and porcelain, used properly and cared for properly, are things that outlast a single human life and are handed on.

Japanese ceramics do, however, have properties that differ from machine-made tableware. They absorb water, they are vulnerable to heat, and their glazes have delicate points. Handle them without knowing this and you can damage a wonderful, singular piece early on.

This article explains proper care in detail by type of Japanese ceramic — so that a piece you value stays with you, cared for, for a long time.

What to Know Before Use: The Basic Properties of Each Material

Care differs greatly by the material of the piece. Knowing which material yours is comes first.

The Properties of Earthenware

Earthenware is fired from clay at a comparatively low temperature, roughly 1,100–1,300°C. Its characteristics are as follows.

• It absorbs water　The surface of earthenware has fine pores that absorb moisture, oil, acid, and alcohol. This is also the foundation of the "growing" that changes a piece the more it is used, but handled wrongly it causes staining and mould.
• Dishwashers are generally out　Sudden temperature change — a dishwasher's hot water plus drying cycle — stresses earthenware, risking the spread of crazing in the glaze or cracking of the body. Durable dishwasher-safe earthenware has increased in recent years, but whether a piece can take it varies by maker, and many cannot.
• Caution with the microwave　Pieces with gold or silver decoration in the glaze, and pieces repaired with kintsugi, cannot go in the microwave. Earthenware without gold can often take brief use, but avoid prolonged heating.
• Representative regions　Bizen ware, Shigaraki ware, Hagi ware, Tamba Tachikui ware, Mashiko ware, Echizen ware and others

The Properties of Porcelain

Porcelain is fired from ceramic stone — containing kaolin among other minerals — at a high temperature of roughly 1,300–1,400°C. Its characteristics are as follows.

• Almost no absorbency　The surface is dense and without pores, so it does not absorb liquid. Dirt does not settle easily and comes away readily.
• Many pieces are dishwasher-safe　Without gold or silver decoration, many can go in the dishwasher, but check the product notes.
• Many pieces are microwave-safe　Porcelain without metallic decoration is usually fine in the microwave.
• Representative regions　Arita ware, Kutani ware, Hasami ware, Tobe ware and others

On the characteristics of each material, the articles below go further — enjoy the differences.

• Earthenware, Stoneware, Porcelain: The Real Differences
• Stoneware vs Porcelain: How to Tell Them Apart

A Little Work Before First Use: Medome

With the difference in materials understood, let us start with the care of earthenware. Before using earthenware for the first time, Japan traditionally performs a treatment called medome, seasoning.

What Medome Is

Medome is the treatment of filling the fine pores of earthenware in advance. Precisely because earthenware stains easily, seasoning lets it absorb first and prevents the absorption of dirt afterwards.

• Prevents early staining and colour transfer
• Prevents the dirt that causes mould and odour from entering
• Makes a piece last longer

How to Do It

The usual method uses water with flour dissolved in it, or rice washing water.

• 1.　Put water with flour dissolved in it, or the cloudy water left from washing rice, into a pot
• 2.　Add the piece so the water covers it entirely
• 3.　Heat slowly on a low to medium flame and stop just before boiling
• 4.　Leave it to cool as it is, 30 minutes to an hour
• 5.　Take it out, rinse under running water, and dry

The starch from the flour or rice fills the pores.

Which Pieces Need It, and Which Do Not

Seasoning is best done on earthenware generally — Hagi ware, Shigaraki ware, Tamba Tachikui ware and the like. Porcelain does not need it, and pieces such as Bizen ware made by the low-absorbency yakishime technique often do not need it either.

Daily Care, by Material

From here, the practical points for using earthenware and porcelain for a long time.

Caring for Earthenware

• Wash soon after eating　Even after seasoning, the oils and acids of food can soak in if they stay in contact for long. Wash as soon as possible after a meal.
• Wash with warm water and a soft sponge　Use no detergent as a rule, or a small amount of neutral detergent at most — especially for shudei teapots and Hagi ware. Detergent left in the pores can emerge at the next use, so take care.
• Dry thoroughly after washing　Storing a piece insufficiently dried causes mould. After wiping the moisture with a towel, turn it upside down and dry it completely.
• Store so pieces do not scratch　Where the surface of earthenware is quite rough, pieces knocking against each other can scratch. When stacking earthenware, place soft cloth or paper towel between pieces to prevent it.

Caring for Porcelain

Porcelain is far easier to handle than earthenware, but it has its cautions.

• Care with the dishwasher　Porcelain with gold, silver, or platinum decoration can lose it in a dishwasher. Hand washing is safe.
• Thinly thrown porcelain is vulnerable to impact　It is strong against water since it does not absorb, but thin porcelain breaks easily on impact. Stack carefully.
• Avoid bleach　It is tempting to use bleach to protect the whiteness of porcelain, but it can damage glaze and painted pigment, so it is best avoided as a rule.

Caring for Nanbu Ironware

Different from ceramics, but often bought as a souvenir by visitors to Japan, Nanbu ironware also deserves an explanation of care.

What Nanbu Ironware Is

Nanbu ironware is traditional cast ironware made in Iwate Prefecture — Morioka and Oshu — for around 400 years. Its distinctive substance, and a plain, robust beauty that gains character the more it is used, are very highly valued not only in Japan but in Europe and America as "Nanbu Ironware."

Nanbu ironware has three major characteristics.

• Excellent heat retention and conduction　Being a mass of iron, once warmed it stays warm and conveys heat evenly to food. Sear a steak and the outside crisps while the inside stays juicy; boil water and it becomes remarkably mellow.
• It supplies iron　During cooking or boiling, readily absorbed ferrous iron dissolves into the food or water. It is known as a kind tool for anyone prone to anaemia.
• Extraordinary lifespan　Sturdy enough that people say "from parent to child, from child to grandchild." Cared for properly it can be used for over a hundred years.

Why It Is Called "Nanbu"

In the Edo period, the lord of the Nanbu domain, which governed what is now northern Iwate, invited tea-kettle craftsmen from Kyoto to make ironware. Drawing on good local iron resources, the industry was protected and developed as an important product of the domain.

Today, at the request of overseas markets beginning with France, colourful Nanbu ironware is made in red, blue, and gold as well as traditional black. That opened the way for it to spread worldwide as a modern item that suits a contemporary kitchen while remaining a traditional craft.

How to Care for It

Nanbu ironware teapots and tea utensils need care quite unlike ceramics.

• Never wash with detergent　Detergent is forbidden on ironware. Rinse with hot water only.
• Dry completely　After use, set it upside down and dry completely. Remaining moisture causes rust.
• Do not wipe the inside　Wiping the interior with a towel strips the protective oxide layer.
• Remove exterior rust gently with hot water　If rust appears on the outside, pour a little hot water over it and rub lightly with a brush. Do not scrub hard.

Common Problems and What to Do

If Mould Appears

Earthenware stored insufficiently dried can grow mould. If that happens, follow these steps.

• 1.　Wash the whole piece in warm water and remove surface mould
• 2.　Apply a paste of baking soda dissolved in water and leave for 30 minutes
• 3.　Rub gently away with a soft brush
• 4.　Rinse well under running water and dry completely

If the mould has soaked into the body, repeating medome to close the pores is effective.

If Tea Stains or Dirt Have Soaked In

Highly absorbent earthenware can take in tea stains and dirt. If so, deal with it as follows.

• 1.　Soak the piece in baking soda water — 1 teaspoon to 200ml — for one to two hours
• 2.　Rub gently with a soft sponge
• 3.　Rinse thoroughly

With Hagi ware, however, tea colour soaking in is welcomed as the "seven transformations." There is something to be said for not forcing it away.

If a Piece Chips or Cracks

Even with a small chip, a piece is not "finished." Repairing it and using it for years is part of the appeal of japanese ceramics.

There is a traditional Japanese repair technique called kintsugi. The chip is joined with lacquer and finished with gold powder, and the repaired piece is reborn as something more beautiful still. Not taking a chip as shame but accepting it as part of a history — this too is the depth of Japan's wabi-sabi culture.

For large breaks or many chips, you can commission kintsugi from a local craft shop or pottery school, or buy a kit and learn it yourself.

If the Glaze Colour Changes

Glaze colour can change over years of use.

• Change from growing, to be welcomed　The seven transformations of Hagi ware, the shifting expression of Bizen ware, the increasing mellowness of Tokoname shudei — these are intentional changes over time.
• Change from deterioration, to be addressed　Glaze peeling, gold disappearing, sudden colour change — these can indicate a problem with how a piece is used or stored. Review your use of the dishwasher and microwave.

That a piece grows is itself an appeal of japanese ceramics. On that appeal, the articles below go further.

• Pottery That 'Grows': How Ceramics Change With Use
• Crazing (Kannyu): Cracks in Glaze That Aren't Damage

Storage for the Long Term

Store by Material

Ideally, store earthenware and porcelain separately. Porcelain is harder, so stacking it with earthenware can scratch the earthenware.

Put a Protective Layer Between Stacked Pieces

When stacking, place thin washi paper, felt, or a silicone mat between pieces. This prevents scratching and keeps air circulating.

Keep Them Somewhere Dry

Earthenware is sensitive to humidity. Store it on an upper shelf or somewhere dry rather than in the damp space under a kitchen sink.

Take Unused Pieces Out Regularly

Even if you are not using a piece, take it out every few months to wash and dry it. Left for long periods, it stays in a state of absorbed moisture, causing mould and odour.

Keeping Japanese Ceramics Outside Japan

Advice for looking after work brought home from Japan or delivered by shipping.

• Adjusting to a different climate　In climates drier than Japan — much of Europe and North America — earthenware can dry out rapidly. For the first few weeks, we recommend using a piece daily so it acclimatises to its new environment.
• Dealing with hard water　Much of Europe has hard water, high in calcium and magnesium. Washing in hard water leaves white limescale on the inside of a piece more readily. Rinsing periodically with lemon water or vinegar water removes it.

Living Alongside Your Ceramics

Caring for japanese ceramics is not difficult. The basics are "wash it soon after use, and dry it thoroughly." That is all. A little knowledge and a little care keep a piece beautiful for decades.

And a well-used piece holds a beauty of time that a machine-made product can never produce. A Hagi tea bowl through its seven transformations, a Bizen yunomi grown mellow, a porcelain plate repaired with kintsugi — these are not damaged pieces but pieces of your own, carrying a rich history.

Begin your long time with a piece you value, here.

Related Articles

Japanese Ceramic Culture and History

• A Short History of Japanese Ceramics, Jomon to Now
• Pottery That 'Grows': How Ceramics Change With Use
• Crazing (Kannyu): Cracks in Glaze That Aren't Damage
• Kintsugi: How to Repair Pottery With Gold (and Why)
• Reading Wabi-Sabi in a Single Bowl

Japan's Kiln Regions

• Japanese Pottery by Region: A Buyer's Map
• Hagi Ware: The Tea Bowl That Changes Colour as You Use It
• Bizen Ware: Pottery With No Glaze at All
• Arita Ware: Japan's First Porcelain, 400 Years On
• Tobe Ware: Shikoku's Thick, Everyday Blue Porcelain

How to Choose Japanese Ceramics

• Stoneware vs Porcelain: How to Tell Them Apart
• Earthenware, Stoneware, Porcelain: The Real Differences
• How to Choose a Japanese Rice Bowl (Chawan)
• Japanese Teapots: Kyusu, Houhin and Dobin Compared

How to Buy Japanese Ceramics

• About Us｜Japanese pottery & culture
• Buying Japanese Pottery Online: What to Check First
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