fresko

Fresco, sometimes written fresko in non-English contexts, is a mural painting technique in which pigment is applied to freshly laid lime plaster. The word derives from the Italian fresco, meaning fresh. In the buon fresco (true fresco) method, pigments are mixed with water and painted onto damp plaster, so the pigment becomes chemically bound to the wall as the plaster dries. A related technique, fresco secco, uses pigments applied to dry plaster and relies on binders or glue to fix the paint, making it easier to retouch but generally less durable.

Process and materials are central to fresco. The wall is prepared with rough plaster (arriccio), followed by a smooth, thin final layer (intonaco) on which the artist works in sections called giornata, completing a defined area before the plaster sets. The lime plaster absorbs the water-based pigments during the chemical setting, creating a durable, long-lasting surface when done correctly. Because buon fresco requires working quickly on a moist substrate, color choices and planning are constrained by the weather, height, and the time needed for each section to cure.

History and legacy. Fresco has ancient roots and was widely used in the Roman world and across medieval and Renaissance Europe. It reached peak complexity in Italian Renaissance murals, with renowned examples such as Giotto’s Scrovegni Chapel and Michelangelo’s Sistine Chapel ceiling. Beyond Italy, fresco-like practices appeared in various cultures, adapting to local materials. Conservation of frescoes is ongoing, given their vulnerability to moisture, structural movement, and surface loss, and restoration aims to stabilize the original techniques and materials.