3. Tratteggio (o rigatino): As its name in Italian, “hatching”, indicates, very thin vertical parallel lines of pure colours are applied, close together, that from a certain distance cannot be distinguished.

4. Neutral ink: A neutral uniform colour is applied on the lost parts. The shade is a compendium of all the colours in the work and it is perceived as being duller.

Ramon de Mur,  Virgin suckling the child [2], circa 1415-1425. Tempera and gold leaf on wood.

Joan Gascó, Altarpiece of Saint Peter [3], circa 1516. Tempera, oil paint, stucco reliefs and gold leaf on wood.