Thin layers and sfumato in the Mona Lisa

Leonardo da Vinci used sfumato—thin, translucent glaze layers—to create gradual transitions between light and shadow, softening edges and giving faces a smoky appearance. Scientific analysis of Leonardo’s paintings, including the Mona Lisa, found individual glaze layers about 1–2 micrometers thick. This measurement refers to thin glaze layers, not the entire thickness of the paint coating.