Comment by xyzzy_plugh

I had a ceramic coffee mug that I loved and used very regularly. I bought it at a fair from a local potter and it had a very unique glaze, lots of blues and greens.

A friend who is a potter saw me drinking out of it and said that the glaze looked suspicious. He said it looked loaded with heavy metals, and that I should probably not use it or at least get it tested.

At the time I knew a guy who worked in a lab that tested certain substances for hazardous materials. He was intrigued and brought it in to work one day, and later texted me asking if I wanted it back, because it was very likely leaching cobalt, lead, and cadmium, and it was probably also very mildly radioactive.

I feel much better drinking out of mugs from IKEA and other big name stores.