Microwave and Dishwasher Safe Japanese Pottery: 73 Makers Answer

When you buy a piece by an individual maker, the worry that stays with you to the end is usually the same. Can this go in the microwave? You do not want the trouble of washing by hand, but can it go in the dishwasher?

Mass-market tableware says so on the back of the box. One-of-a-kind pieces have no box. Here, after collecting the actual answers from 73 makers whose work nokaze carries, we set out how to judge for yourself before you buy.

In Short: The Microwave Usually Passes, the Oven Almost Never Does

Here is what the 73 makers said about their own work.

Nine in ten say no to the oven. Apart from pieces built from heatproof clay as donabe or gratin dishes, work by individual makers is not designed for a direct flame or an oven. When you want heatproof ware, choose something made from heatproof clay in the first place. Unless a piece says it takes the oven, assume it does not.

Microwave and dishwasher are roughly half and half. People sometimes say "everything by a maker is hand wash only," but in fact more than four in ten say the microwave is no problem.

Material Decides Eighty Percent of It

Material is where judging starts. The tendency divides clearly not by maker but by what the piece is made of.

With porcelain the material is durable, so you can generally take microwave and dishwasher as fine. Pottery is where makers differ most. With silver overglaze and the like the material often rules the microwave out, but otherwise makers frequently answer "no" on the safe side, fearing breakage. Ask them directly and many will say a short burst is fine. Put the maker's judgment first, and where you can, talk to them and decide from there.

Glass, wood and lacquer really are difficult. That is the largest divide of all. Knowing the difference between pottery and porcelain lets you judge in a shop as well.

Four Things to Look at Before You Buy

Even when the product page does not say, there are things you can judge from a photograph.

• Is gold or silver used?　Kinsai gold and ginsai silver are metal. Put them in a microwave and they spark. A single fine gold line around the rim is enough to rule it out.
• Is bare clay visible underneath?　If the kodai foot ring carries no glaze and the clay looks rough when you turn the piece over, it absorbs water. It does not suit the long high-temperature drying of a dishwasher.
• Are there fine cracks on the surface?　That is crazing. It is not damage, but moisture enters through it. Heat the piece suddenly in a microwave and the moisture it holds expands, putting a load on the body.
• Is it extremely thin?　The thinner the piece, the weaker it is to a change in temperature. Porcelain thrown thin at the rim especially will chip against other dishes inside a dishwasher.

What "Conditional" Actually Means

What we counted as "conditional" is where a maker answered that they would not say it cannot be done, but do not recommend it. Specifically it means the following.

• Microwave　Reheating for a short time is fine. Heating straight from frozen, or heating an empty piece, is not
• Dishwasher　It will not break, but keep it up and color enters the crazing and the gloss of the glaze drops. Save it for days when you are in a hurry
• Oven　Low temperature without preheating is fine. A direct flame and the grill are not

What to Do Before First Use

For absorbent pieces, doing medome sealing at the start keeps stains from getting in. Simmer the piece gently in rice-rinsing water for about twenty minutes, let it cool as it is, then wash it. That is all.

Doing this also reduces the smells a piece picks up when you heat it in a microwave. It does not make the piece itself stronger, but it certainly widens the range of what you can do with it.

The Order to Check In

When you cannot decide, check in this order.

• 1. What the product page says　At nokaze we list suitability maker by maker.
• 2. Material　Porcelain you can trust. Glass, wood and lacquer are not possible.
• 3. Gold, silver and crazing　If either is present, keep it out of the microwave.
• 4. When in doubt, wash by hand　With any piece, washing by hand and drying it will cause no trouble.

Related Articles

Material and Care

• Stoneware vs Porcelain: How to Tell Them Apart
• Japanese Stoneware Care: What Porcelain Never Needs
• How to Care for Japanese Ceramics: A Practical Guide
• Medome: How to Seal Unglazed Pottery Before First Use

Reading a Piece

• Crazing (Kannyu): Cracks in Glaze That Aren't Damage
• Kodai (Foot Ring): The Part Collectors Check First
• How to Choose a Donabe | Size, Glaze, First Use and Care