What adhesive must be applied and allowed to set before placing gold or silver leaf?

• A. The waxy adhesive
• B. PVA glue
• C. The size (mordant), which can be water-based or oil-based.
• D. Shellac

Answer: (C)

Gilding with gold or silver leaf relies on a sizing (also called mordant) that becomes tacky so the leaf can cling to the surface. The important point is that the leaf will only adhere when the adhesive has set to the right level of tack—sticky enough to grab the leaf, but not so wet that it slides off. Size can be water-based or oil-based, and the choice affects drying time and working time, so you apply it and let it reach that tacky stage before placing the leaf.

Waxy adhesive isn’t used here because wax doesn’t create the proper tack needed for leaf adhesion and can blur or smear the thin metal. PVA glue dries hard and does not provide the lean, tacky surface leaf needs. Shellac is a sealer or finish in gilding contexts, not the sizing that creates the required tack for leaf adhesion.