What is 'sgraffito' in the context of painting techniques?

Sgraffito is a technique where the artist scratches through a surface layer to reveal a different color or texture underneath. This method is often utilized in ceramics and murals, providing a way to create intricate designs and patterns with a striking visual contrast. The process involves applying a layer of paint or slip and then using a sharp tool to scratch away the top layer, revealing the hue of the layer beneath. This can add depth and complexity to the artwork, allowing for creative expression in the textures and designs.

The other choices describe different techniques within painting but do not specifically define sgraffito. Layering paint focuses on adding materials for texture, applying paint while it's wet refers to techniques like wet-on-wet painting, and using diluted paint pertains to methods that aim for transparency or soft effects rather than revealing underlying colors.