The suribachi is the Japanese version of the mortar; and the pestle is called a surikogi. It is the traditional Japanese food grinder. In Japanese cooking the suribachi is used to crush sesame seed as well as for various pastes. Grooved inside for hard to grind seeds, nuts and herbs this Suribachi measures 6" in diameter. Recommended for whole food and macrobiotic cooking. And it is a beautiful cobalt blue. I just saw Alice Waters from Chez Panisse use one of these to make vinagrette. Japan.