Not all materials can go in the microwave. It’s understandable if you’re worried about putting your porcelain mug in the microwave and potentially breaking a perfectly good mug. So, are porcelain mugs microwave-safe?
Most porcelain mugs can go in the microwave. Porcelain, and pottery in general, is usually microwave-safe.
What makes a porcelain mug microwave-safe?
To understand why porcelain mugs—and porcelain in general—is microwave-safe, you should first understand how porcelain is made. Porcelain is similar to ceramic (which is also a microwave-safe material). Both are made from clay, and both are fired in a kiln to dry and set the clay design. However, porcelain is made from clay which is more refined and is fired at a higher temperature than ceramic, making it denser and even more durable than ceramic.
The process of creating a porcelain mug or dish involves heating the porcelain to around 1400 degrees Celsius or 2550 Fahrenheit. Your porcelain mug will of course never reach these sorts of temperatures in the microwave—this is the reason porcelain is generally microwave-safe.
For extra peace of mind, try looking at your mug to find a microwave-safe symbol. There isn’t a universally identical symbol to indicate something is microwave-safe, but usually, the symbol has three wavy lines and may be surrounded by a rectangle or a simple 2D microwave illustration. Sometimes mugs and dishes more explicitly have “microwave-safe” written on them—usually on the bottom.
How can I test if my porcelain mug is microwave-safe?
If you can’t find a microwave-safe symbol on your mug and you want to be extra sure that your favorite mug won’t be harmed in your microwave, there is an experiment you can do to learn if your porcelain mug is truly microwave-safe or not. Here’s how you do it:
- Get a mug that you know for sure is microwave-safe (look for a microwave-safe symbol) and fill it with water from the tap.
- Put this known microwave-safe mug filled with water and your porcelain mug that you want to test into the microwave with a distance between them.
- Microwave the two mugs on a high setting for 1 minute.
- Remove both mugs while being careful not to burn your hands (you may need to use oven mitts).
- Check which mug is hot and which mug is cold. If the mug of water is hot and the porcelain mug that you’re testing is cold, that means that your porcelain mug is microwave-safe. If the mug of water is cold or cool and your porcelain mug is hot, this means your porcelain mug is not microwave-safe.
This experiment works because it’s testing whether or not your porcelain mug is absorbing high levels of heat. If a mug or dish absorbs high levels of heat, it isn’t microwave-safe.
When should I not put a porcelain mug in the microwave?
Not many, but still some porcelain mugs, will not be microwave-safe. Firstly, if the maker of the mug has stated anywhere on the mug or the packaging that it should not be microwaved, then you should definitely heed that warning. It could be that the mug’s finishing is not microwave-safe.
Some porcelain mugs won’t be microwave-safe because they have metallic finishing, trim, or paint—if you were to microwave such a porcelain mug, sparks would be created and you could even start a fire.
So, can you put porcelain mugs in the microwave? Yes, you can, usually. To make a porcelain mug it must be fired in an oven at exceedingly high temperatures. Because your mug will never encounter such high temperatures in a microwave, it means there should be no problem with it getting zapped in the microwave.
If in doubt, you can test the microwave ability of your porcelain mug with the simple experiment described above. This allows you to see if your mug absorbs too much heat to be microwave-safe.