Mucilage is usually formed by river sediments under strong pressure and humid environment. In the process of formation, the clay gradually approaches the ground, and the pressure gradually decreases, so it becomes a clay like plastic solid with strong adhesion.

Clay is a kind of clay plastic solid with strong viscosity. This type of plastic solid usually consists of solid or liquid adhesives with adhesive properties and powder fillers with certain functions., Appropriate pigments and auxiliary materials can be added as needed. Most of them act as seals.