What is the name of the rough initial coating of plaster used in fresco painting?

The rough initial coating of plaster used in fresco painting is known as arriccio. This initial layer serves as a foundational surface applied to the wall, which provides a textured background for subsequent layers of plaster. Once the arriccio is dry, artists can apply a finer layer called intonaco, onto which the actual fresco painting is executed. The arriccio is typically coarser and thicker compared to the smoother intonaco, allowing for better adhesion and a more substantial structure to support the finished artwork. This layering technique is vital in the fresco process, ensuring that the pigments bind well to the surface, creating a durable and vibrant mural when the plaster dries.