A mortar for grinding sumi inksticks so as to produce enough liquid ink necessary to write a manuscript or paint a picture. The inkstone, which is generally made of stone but can also be ceramic or metal, has a border rim to contain the liquid, while the central grinding area slants downward towards a water reservoir. The wetted end of the inkstick rubbed against the stone in the presence of a small amount of water releases the black soot in the inkstick. The grinding continues until a sufficiently dark color is achieved.