The surface behavior of gilding layer imitations on polychrome artefacts of cultural heritage

• Published in: Surface and interface analysis 2011-08, Vol.43 (8), p.1171-1181
• Main Authors: Sandu, I. C. A, Busani, T., de Sá, M. H.
• Format: Article
• Language: English
• Subjects: Artefacts; Atomic force microscopy; colorimetry; Copper; cultural heritage; gilded surfaces; Gilding; Gold; imitations; Markets; Roughness; stratigraphical structure; Topography
• ISSN: 0142-2421; 1096-9918; 1096-9918
• DOI: 10.1002/sia.3796

This paper proposes the first results of a larger study on the behavior of gilded surfaces of polychrome heritage artefacts with the aim to understanding the surface patterns and roughness variations before and after specific treatments (burnishing and varnishing). This study can be useful to trace correlations between the compositional features, manufacturing and applications/elaboration processes of gilding layers and the pattern of the surface topography, and also some insights into the degradation/corrosion mechanisms. The results obtained on imitations of gilded surfaces can be further useful for recognizing fake surfaces in the authentication of artefacts from the antiquity markets. Two types of commercial imitations of gilded surfaces on a wooden support were considered: liquid ‘gold’ (Cu‐Zn powder in a solvent) and ‘gold’ leaf (Cu‐Zn leaf) applied over bole and gesso layers. A combined analytical approach using atomic force microscopy (AFM), optical microscopy (OM) and colorimetry (CIE L*a*b* system) was applied in order to better understand the behavior of the gilded‐varnished surface and of the interface between the metal surface and the other preparative layers. Copyright © 2011 John Wiley & Sons, Ltd.