Slip — viscous or liquid mixture of clay, water and other additives that can be used as a glaze, a bonding agent, or a casting material.

One use of slip is for coating the surface of tiles before glazing. The slip is evenly applied onto the tile, providing a smooth and uniform base for the glaze to adhere to. This helps to enhance the appearance of the glaze and create a more even and glossy finish.

Slip is also used for decorative purposes. It can be coloured using ceramic pigments or oxides, allowing for the creation of vibrant and intricate designs on the surface of the tile. Decorative slip can be applied using various techniques such as painting, stencilling, or trailing, depending on the desired effect.

In addition to its decorative applications, slip can also be used for repairing or filling in gaps. It can be applied to cracks or chipped areas to restore the integrity of the tile and create a seamless surface.