Visualising Iron Gall Ink Underdrawings In 16th Century Paintings In-Situ By Micro-XRF Scanning (MA-XRF) And LED-Excited IRR (LEDE-IRR)

Until today, iron gall ink is classified as an exceptional underdrawing material for paintings. A certain identification is always based on invasive analysis. This article presents a new non-destructive analysis approach using micro-X-ray fluorescence scanning (MA-XRF), LED-excited IRR (LEDE-IRR) using a narrow wavelength-range of infrared radiation (IR) and stereomicroscopy for visualising and identifying iron gall ink underdrawings. To assess possibilities and limits of this non-invasive approach, results were compared to invasive examinations on cross-sections using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX). The approach is tested on panel paintings of Hans Holbein the Elder and Giovanni Battista Cima da Conegliano. The holistic setup could successfully visualise underdrawing lines made with iron gall inks, which formerly remained invisible by means of conventional IRR. For the first time, a direct access to a formerly invisible type of underdrawing is created, allowing to harness the whole iron gall ink underdrawing for interdisciplinary studies.

Recto and Verso: The Pictorial Fronts and the Marbled Reverses of Two Flemish Panel Paintings

From the first third of the 15th century onwards, panel paintings with marbled reverses increasingly appeared in Flemish art. The fronts of these panels primarily depicted religious narrative scenes or portraits. The backs were decorated with an abstract pattern, referred to as marbling. These painted marble facsimiles often differed in terms of design from other examples of stone imitations such as those used on the frame decorations of other panels. Unlike these frames, which suggest a greater illusionistic intention, the marbled reverses appear to function as abstract ornamentation. However, this article proposes that the painted backs are thematically linked to the pictorial narratives of the fronts. The marbled backs of Rogier van der Weyden’s Crucifixion and the Portrait of Margareta van Eyck will be considered in the context of a profane and a theological iconography. Both panels feature a reverse that can be identified as both an imitation of red porphyry and a representation of liquid paint. Metaphysical, material–semantic, and theological references will be revealed in the pictorial examples.

The Origin of Icons

The origin of icons, and by extension of Christian painting, can now be traced to the panel painting tradition of pagan divinities in wide use in Late Antiquity throughout the Mediterranean. Both pagan and Christian panel paintings were employed as votive or thank offerings. According to an ancient phenomenon known as “syncretism,” emperors were identified with gods and Greek gods with Egyptian ones. Triptych paintings were a new way of exploring the implications of syncretism. In the sixth century, icons went from being single offerings to an assembly on the templon barrier. The earliest surviving evidence of church iconography, decoration and ritual cult, or liturgy, comes from Constantinople, at the churches of St. Polyeuktos and Hagia Sophia.

Three-dimensional numerical and experimental study of fracture saturation in panel paintings

Panel paintings—complex multi-layer structures consisting of wood support and a paint layer composed of a preparatory layer of gesso, paints, and varnishes—are among the category of cultural objects most vulnerable to relative humidity fluctuations and frequently found in museum collections. The current environmental specifications in museums have been derived using the criterion of crack initiation in an undamaged, usually new gesso layer laid on wood. In reality, historical paintings exhibit complex crack patterns called craquelures. The present paper analyses the structural response of a paint layer with a virtual network of rectangular cracks under environmental loadings using a three-dimensional model of a panel painting. Two modes of loading are considered—one induced by one-dimensional moisture response of wood support, termed the tangential loading, and the other isotropic induced by drying shrinkage of the gesso layer. The superposition of the two modes is also analysed. The modelling showed that minimum distances between cracks parallel to the wood grain depended on the gesso stiffness under the tangential loading. Despite a nonzero Poisson’s ratio, gesso cracks perpendicular to the wood grain could not be generated by the moisture response of the wood support. The isotropic drying shrinkage of gesso produced cracks that were almost evenly spaced in both directions. The modelling results were cross-checked with crack patterns obtained on a mock-up of a panel painting exposed to several extreme environmental variations in an environmental chamber.

The rediscovery of an Adoration of the Shepherds by Jacques Jordaens: a multidisciplinary approach combining dendroarchaeology and art history

The implementation of multidisciplinary research approaches is an essential prerequisite to obtain comprehensive insights into the life and works of the old masters and their timeline in the production of the arts. In this study, traditional art history, cultural heritage, and natural science methods were combined to shed light on an Adoration of the Shepherds painting by Jacques Jordaens (1593–1678), which until now had been considered as a copy. From dendrochronological analysis of the wooden support, it was concluded that the planks in the panel painting were made from Baltic oak trees felled after 1608. An independent dating based on the panel maker’s mark, and the guild’s quality control marks suggests a production period of the panel between 1617 and 1627. Furthermore, the size of the panel corresponds to the dimension known as salvator, which was commonly used for religious paintings during the period 1615 to 1621. Finally, the interpretation of the stylistic elements of the painting suggests that it was made by Jordaens between 1616 and 1618. To conclude, from the synthesis of: (i) dendrochronological analysis, (ii) panel makers’ punch mark and Antwerp Guild brand marks, (iii) re-examination of secondary sources, and (iv) stylistic comparisons to other Jordaens paintings, we suggest that the examined Adoration of the Shepherds should be considered as an original by Jordaens and likely painted in the period 1617–1618. The study is a striking example of the effectiveness of a multidisciplinary approach to investigate panel paintings.