Animal glue is mixed with lampblack to make traditional Chinese ink sticks.
The glue binds the fine carbon particles into a workable solid and later helps disperse them when the stick is rubbed with water. Traditional glues could be made from materials such as ox hide, fish skin, or other animal tissues. The precise recipe varied according to the desired hardness, sheen, flow, color, fragrance, and durability.
Inksticks are not used like a modern liquid bottle of ink. A calligrapher places a small amount of water on an inkstone and grinds the stick against it in circular motions. More grinding produces a denser, darker ink, while more water creates a lighter wash suitable for painting.
A common confusion is gum arabic, which is a familiar binder in some Western and modern artists’ inks. Traditional Chinese inksticks are characteristically associated with soot and animal glue. Makers sometimes added incense, medicinal herbs, or musk for scent, preservation, or prestige.