Is handmade pottery microwave safe?

I have noticed that there is still a lot of confusion whether handmade pottery is microwave safe. Sometimes all ceramics are considered unsuitable for use in the microwave.

But rest assured, your favorite handmade cup or plate can be absolutely suitable for the microwave, provided the ware does not absorb water(!). In addition, the piece should be finished with a suitable glaze for daily use. But that is always important, not only for microwave use.

So you can use handmade pottery as you like, even in the microwave.

Microwave safe ceramicware: ASTM standard

As stated, the most important thing is that functional pottery does not absorb water. When that happens, the microwave heats this water to steam and the ware itself becomes very hot indeed(!). Therefore, an international standard has been developed by the ASTM. It sets quality levels which assures the heating of food can be carried out safely.

If ceramicware meet this standard, it is considered ‘microwave safe’. Please note that the microwave does not heat the ware (much), but it does heat the food in or on it. The ceramicware can therefore in turn get hot from that.

Stoneware and porcelain (if fired correctly) absorb less than 1 percent water and are therefore almost by definition “microwave safe”. Some earthenware (whose clay is specially designed for low absorption at lower temperature) may be also suitable, but that is less common.

Handmade pottery can be microwave safe

Of course, the glaze of the handmade ceramics must be suitable for use (non-toxic and preferably also dishwasher resistant). And besides that, do not have a metal luster decoration, such as a gold-colored border on the lip of a cup. Such a (very thin) layer of metal can cause sparks in the microwave. That’s why you can’t put cutlery in the microwave .

So with this in mind: use handmade pottery with great pleasure, also in the microwave.

Chocolate Cup Cake

I make stoneware for daily use, including dishwasher and microwave. Looking for handmade functional pottery? Take a look in my webshop.

Do you have your favorite cup already at home? Then go enjoy it immediately. For example, by baking a “Chocolate Cup Cake” in the microwave…

Self-raising flour, cocoa powder, sugar, (sunflower) oil and milk at hand? Make a delicious“Chocolate Mug Cake” within 5 minutes. The recipe I used came from Laura’s site at Laura’s Bakery (sorry text in Dutch only) but there are many other quick microwave recipes to be found.