Ceramics Care


How to take care of your
Japanese ceramics

The Nature of Clay

It is important to know that pottery will gradually change color over time.  This is both expected and appreciated in Japan and, in no way, means that the work is somehow flawed.  It is the nature of clay.

Seeing your favorite saké cup or tea ceremony bowl take on a different character over the years is a pleasure that only deepens the meaning of the piece.

A fine piece of pottery, when properly cared for, promises a lifetime of delight and discovery.

image of artist's hands at work

Tea Ceremony Bowls

When a tea ceremony bowl (chawan) is used over many years, the compounds naurally found in green tea will form a patina on the surface.  At first glance, one might think that it appears dingy and not quite the same as when it was new.  Over time, though, tea ceremony bowls will take on a beautiful sense of age and history.

The cracks in the glaze, formed naturally while cooling in the kiln, will deepen in color and form intricate mosaics; the patina will become a beautiful gradation of various colors, and a rich luster will appear over smoother areas.  In the same way that antique wood or old copper is considered beautiful in the West, the same can be said for the changing character of chawan.

Washing Tea Ceremony Bowls

Tea ceremony bowls are normally soaked in warm water before use so that whipped green tea (matcha) doesn't sink in too quickly.  Such preparation isn't necessary for porcelain tea bowls or those with uniform overglazes such as celadon or tenmoku.

Afterwards, tea bowls are rinsed with water, wiped clean with a cloth, and then left out to dry naturally.  They are not usually washed with soap and never cleaned in automatic dishwashers.

image of tea ceremony bowl

Ōizumi Yōhen Tea Ceremony Bowl
by Wada Tōzan

Preparing for Use · Cleaning

Tableware made of clay should first be boiled for 20 minutes and allowed to cool naturally.  This should be sufficient to sterilize the piece.

Place the item in a pan of water, bring to a gentle boil over a low flame, and allow to cool to room temperature.

Cleaning Ceramics

We recommend washing all fine ceramics by hand with a soft sponge and as little dishwashing liquid as possible.  If you do use a dishwasher, please choose a mild detergent as some brands are quite abrasive and can gradually dull the surface of pottery & porcelain over years of use.

If not properly dried, the unglazed areas on pottery can develop mildew, especially in times of high humidity.  In such cases, soak the piece overnight in water and a capful of bleach.  Repeat if necessary.  When clean, soak again in water overnight and allow to dry thoroughly.

image of teaware

Green Tea Cups & Pots
by Kotoura Kiln


Although most ceramics can be used in microwave ovens, 2000 Cranes advises customers to first heat food in microwave-safe dishes whenever possible.

The works we sell are all formed, glazed, and fired by artists following centuries-old techniques.  They were not intended for use in the microwave.


Water and other liquids permeate works of clay much easier than those of porcelain.  When exposed to microwaves, these liquids become super-heated, expanding then contracting rapidly.  Repeated heating will weaken the integrity of pottery over time and make it more susceptible to damage.


Porcelain ware is more resistant than pottery to the heat stress created by microwaving.  However, works with gold or silver detailing should never be used in microwave ovens.

image of sake flask

Noborigama Climbing Kiln
tended by Kawai Tōru

Warming Saké

It is not uncommon in Japan to simply rinse saké flasks and cups with warm water after use.  This is often sufficient to cut the sticky residue from leftover saké.  On some occasions, though, it may be necessary to use a drop of mild detergent to wash out the inside.

After washing, turn the flask upside down and let it drain overnight.  If not properly dried, the footring area can develop mold.  In such cases, soak the flask overnight in water and a cap-full of bleach.  Repeat if necessary.

Warming Saké

Saké has traditionally been served warm, although many types of saké today are served slightly chilled.  When warming saké, it is important to remember that overheating it can destroy its flavor.

Saké is easily warmed by first placing a filled flask in a saucepan of water and then heating the water over a medium-low flame.

Generally, warm saké is best when served just above body temperature, about 100-104°F (40 to 45°C).

Vessels for saké come in a variety of sizes and forms.  Flasks with thin necks or gourd shapes should not be used in the microwave, as the high pressure that builds up within their narrow interiors during heating can cause boiling saké to erupt out of the flask.

image of sake flask

Ash Glazed Saké Flasks
by Ikai Yūichi

Tenmoku Pottery

The lustrous quality of tenmoku pottery is the result of an overload of iron oxide in the glaze.  Because microwaves cannot pass through easily, the surface of tenmoku works can heat up extremely fast without warming saké or green tea sufficiently within.

2000 Cranes advises customers to avoid using pottery with high iron-content glazes in the microwave at any time.

image of sake cup

Yōhen Yuteki Tenmoku Saké Cup
by Kamada Kōji

Raku Pottery

Raku bowls are fired in a process quite unlike other types of pottery.  They are quite delicate and naturally porous, so particular care should be taken when using them:

  • Raku bowls should be used solely for the preparation of matcha green tea.

  • Do not sterilize the bowl by boiling or washing with a chlorine detergent.

  • Raku bowls are traditionally wiped clean after use.  If you choose to wash the bowl, use a mild, chlorine-free detergent and a soft washcloth.  Do not wash in a washing machine.

  • Before using the bowl for the first time, soak in lukewarm water for one or two minutes.  This will ensure that matcha does not infuse the porous glaze too quickly.

  • If the bowl has been stored for a long time, soak again before use.

  • Before storing the bowl in its presentation box (ki-bako), let dry for 4 to 7 days.

  • Raku bowls are made from a sandy clay which is quite lightweight and delicate.  They do not resonate like high-fired pottery and, thus, make a dull tok-tok sound when tapped on the side.

image of raku tea bowl

Kuro Raku Tea Ceremony Bowl
by Sawada Hiroyuki

Shino Pottery

Because of the porous nature of shino glazes, the color of the item will gradually change after repeated use.

As green or black tea seeps in, the lattice of fine cracks in the glaze becomes more pronounced, eventually forming a darker gradation around the entire piece.  Saké, as well, will make the pink hues in shino deeper and more lustrous.

These changes are both expected and appreciated in Japan and do not mean that the work is somehow flawed.  It is the nature of shino.

image of shino green tea cup

Shino Green Tea Cup
by Suzuki Tomio

Ribbon Tying

Many of the works we sell at 2000 Cranes come with a ki-bako presentation box which is made to order and handcrafted for each piece.  The accompanying ribbon is tied in a butterfly knot called cho cho musubi.

See our ribbon tying page for step-by-step instructions on making cho cho musubi - a skill any serious pottery collector should master.

The Footring

The footring on a piece of pottery is the best way to appreciate the quality, texture, and "flavor" of the clay from which the work is formed.  It also serves as a good indication of the potter's technical skills.

Many of the works we sell at 2000 Cranes have rough, unglazed footrings which have the potential to scratch table surfaces or stainless steel sink areas.  We advise using a serving tray or placemat underneath tableware of this kind.

When stacking plates and bowls, it is best to keep sheets of paper (any kind will do) between them in order to keep the footring from scratching the glaze on the dish below.

image of footring

Ash Glazed Plate Set
by Ikai Yūichi

Chilling Beer Glasses

2000 Cranes recommends chilling beer glasses in the freezer first before use.  Pottery glasses tend to release carbon dioxide in beer more quickly than glass, thus giving beer a very foamy head.  This can be prevented if iced over first.

As with all fine ceramics, you should be careful not to expose pottery glasses to sudden changes in temperature.

image of pottery beer glasses

Yakishimé Beer Glass Set
by Wada Hiroaki

Have a question not answered here? Contact 2000 Cranes.