A mortar made of ceramic.
This is used to finely grind the specks of suihi pigments and gofun (white shell pigments). By grinding it neatly, it smooths out the paint, and creates good color.
It can also be used when making watercolor paints.
12cm is an easy-to-use size that fits in one hand. 6 cm is suitable for making small amounts of paint.
There are small to large sizes, available according to uses.