GLUE - Arabic in pottery.
Arabic glue is a natural product and will burn away when fired, it is a gummy substance taken from a certain tree and is used in pharmaceutical work, mixed with food, inks and colors for printing. In ceramics it is used as a retainer, to hold colors on to a glazed surface that they cannot normally adhere to, as with the on-glaze method.
Rub the part that has to be repaired or painted with a thin layer of glue and leave it to dry. As the surface is glazed, nonabsorbent, this will stop the colors from running. When you have finished painting, carefully cover the part with a thin layer of glaze and then fire it again. This gives a varnished surface, like the rest of the tile, to the part you have repaired.
The next section; Glue – Glaze-base as a glue