The outline of the figures in the composition would then be drawn on the white gessoed surface, using charcoal, ink or paint. However, the boundary between the painted and gilded areas would be incised with a stylus into the gesso, thus registering a clearer demarcation when covered by the semi-opaque gold leaf, than would be apparent if the boundary line was merely drawn.
The composition of the painting required careful planning since the gilding of the background and haloes was carried out before painting took place. Once the gilding had taken place it could not be moved.
