Made of ceramic, black matte surface, can be written on with chalk or chalk pens, which is a neat touch. Both the large handle and cork bottom are great for grasping the mug. When it filled with hot coffee, no worry about burning your hand or fingers. The cork bottom not only insulates the heat but also prevents scratching and staining. The lid of itself features a sliding door on top, and the lid sealed along the edges with a rubber gasket which not only traps in heat but also prevents spills so that you can drink easily. Awesome for your next cup of coffee or tea!