The large oiva mug is made of white stoneware that is dishwasher, oven, microwave and freezer proof. the mug features the tiiliskivi pattern made with a relief technique.please remove the sticker from the bottom of the product before use. the sticker contains a small amount of metal.the tiiliskivi (brick) print was designed by marimekko’s founder armi ratia. the pattern reflects her belief in the simple beauty of everyday life.