Ceramic. Hand-thrown by HEM. 

These mugs ultimately didn't achieve the standards for our first run of products, but have given us valuable insight into what we believe will be the perfect design ready for the public very soon. That said, we still believe they should make it into the hands of people who will use them to the fullest.

Dishwasher and microwave safe. 

Caution: These mugs transfer heat rather easily. Hot beverages will warm the mug rapidly.