Porcelain. Microwave and dishwasher safe. Made in Japan. Do not overheat in the microwave or heat without water. Wash with care. Do not use abrasive cleansers or steel wool. Product size and shape varies in each item due to manufacturing process.
 
Size" 3.4"(R) x 3.4"(H) x 4.4"(W) / 10.2 oz