12 oz thick enamel-coated steel mug
They are heavy (for enamel mugs-- still lighter than ceramic), smooth, wonderful to drink from, and crazy sturdy. You can abuse the heck out of them.
Toss these into a bag to take on a picnic, or take camping and abuse liberally. They're good for sneaky cups of wine or whiskey wherever you happen to be.
MICROWAVE & DISHWASHER USE:
These are steel under enamel. So please don't use them in the microwave.
They are dishwasher safe and won't fade... though keep in mind that metal does rust, so any chips in the enamel will allow the steel underneath to rust if you put it in the dishwasher. But in general... dishwashing should be fine.