If your Large Mug has metallic rims or lettering, then they are NOT microwave safe, and you should never put metallic finished mugs (no matter how small the finish is) in the microwave. Microwaves and metal don’t mix the metal will get very hot and might burn you, or your microwave and in extreme cases could even destroy your appliance. Don’t do it EVER.
Apart from Metallic Mugs most mugs are Microwave safe if the mug is made from one of the materials listed below should be good to go just to be sure please check the specifications from the mug maker, most manufacturers will state if their mug is microwave safe or not.
Microwave Safe Mug Materials (as long as they have no metal finishes)
- Stoneware
- Earthenware
- Bone China
- Fine Bone China
- Brocillate Glass
- Some Plastic