Called "Ghostwave" in China, Agateware Ceramics are made from different colors of clay, wedged together then thrown on the wheel. After it is trimmed, the pulled handle is attached, then it is sanded before being covered with a food-safe transparent glaze. Finally it is fired to bring out the beauty of the colors and the design..This mug stands 4 inches tall and holds 14 oz. of liquid, hot or cold.It can have boiling water poured in it, it can go in the microwave, it can go in the dishwasher, although it is always preferable to handwash any handmade pottery.