The oil gilding technique is more recent and easier than water gilding. It doesn’t require a preliminary surface preparation as it is sufficient for the surface to be smooth and uniform. The gold leaf is stuck to the surface by applying an adhesive called “size.” The choice of the right adhesive depends on various factors:

• Water-based and “Wunda” sizes for surfaces with medium porosity, such as wood, plaster, stucco, and paper;

• Alcohol-based sizes for smooth and compact surfaces like metal, plastic, and glass;

• Oil-based sizes are primarily used for gilding on metal in outdoor environments.