A multi-analytical approach for the characterization of seventeenth century decorative wall paintings in two Norwegian stave churches: A case study at Eidsborg and Heddal, Norway

Abstract

The presented research examines 17th century distemper paint from the polychrome wooden interiors of two Norwegian stave churches: Eidsborg and Heddal. For the first time, the inor-ganic and organic components of specimens from Eidsborg and Heddal were identified using X-ray Diffraction (XRD), Environmental Scanning Electron Microscopy (ESEM)—Energy Dispersive X-ray Spectroscopy (EDS), Fourier-Transform Infrared (FT-IR) spectroscopy, Enzyme-Linked Immunosor-bent Assay (ELISA), and Gas Chromatography-Mass Spectrometry (GC-MS) after derivatization. This multi-analytical approach allowed for the identification of red ochre as the main red pigment within the topcoat (with the possible addition of minium), confirmed that a chalk basecoat was used, and finally permitted the recognition of alteration phases. Markers of proteinaceous material attributed to the use of animal-based glues were detected throughout the stratigraphic layers of both churches, with the addition of linseed oil in some locations. Furthermore, the wood substrate showed markers characteristic of pine tree, with contamination of wood fractions being detected in some of the paint samples from Heddal and Eidsborg. This research has contributed to a better understanding of the current preservation state of Heddal and Eidsborg, and ultimately assisted in developing a deeper comprehension and awareness of materials used in Norwegian stave churches.