A coffee mug is one of the most important items in my shop and environs. This morning, I dropped knocked my Festool mug from a height of about two metres onto the concrete floor in my garage. The mug survived. I knew that it was made of strong porcelain, but I did not know that it was that strong.
Attached are two photos. One of a mug in use and another showing most of my Festool mug "collection".