Harling is very similar to stucco, and is a lime-based wall finish used in Scotland and Ireland. The lime cement and small-aggregate mix is usually applied in two layers, each ⅜–⅝ in thick, and then limewashed—often requiring several coats. Like stucco, harling has to breathe. The stonework beneath is first pointed and voids are filled. Pebble-dash is a twentieth-century development, in which the pebble aggregate is thrown onto the wet cement surface.