Rubik's Cube Melting Warped Ceramic Mug Uh-oh! Either your coffee is too hot or that mug is melting on its own. The inventive design of this Rubik's Cube Melting Warped Ceramic Mug will make you the talk of the office! This mug holds approximately 8 oz., but you better drink up before the cup is just a puddle! Hand wash only. Not dishwasher safe. Do not microwave.