Testing water absorption in earthenware

[Cer@mic_Whisperer]

I just tried a little experiment with an old handmade mug that's been stored in a damp cupboard for months. I was curious to see if the absorbed moisture would cause it to crack or even explode in the microwave. So, I microwaved it empty for 10 minutes. It got really hot, and I noticed some minor crazing, but thankfully no explosion. I'm wondering if anyone else has experimented with different types of clay or firing temperatures in similar conditions?

 

[Glasingvasing]

And with good reason. A microwave works by vibrating water molecules which heats up things, meaning that any material that that has moisture will have this result. Perfectly normal. Haven't done any testing myself to be honest.