A grinding stone usually has a reservoir for water next to the surface on which you grind the ink blocks. The most famous type of grinding stone is the Chinese Tan-kei. Ink blocks or sticks are made by pressing different pigments together. Sumi-e distinguishes between blue and brown ink sticks. Very popular in Japan, blue ink is made from the soot of burned pine wood.
Brown ink is made from the soot of rape seed oil.
The brown ink pigment particles are smaller and reflect more light. Ink sticks often contain animal fats as binders. As a result, they can spoil or mildew quickly if they are not stored properly. Take great care in drying the ink stick after use and wrapping it. In addition to ink sticks, there are also ready-made liquid inks available.