Gelatins are proteinaceous natural materials that are widely used in areas such as conservation and restoration of artifacts as adhesives and consolidants, in pharmaceutics as drug delivery carriers, and in the food industry as structurants. Herein, type A porcine gelatin adhesive films are prepared via solution casting method and their physical and mechanical properties are investigated using X‐ray diffraction (XRD), differential scanning calorimetry, contact angle measurement, dynamic mechanical analysis, and uniaxial tensile tests. The results demonstrate a linear correlation between microstructure of gelatin films in terms of their triple‐helix content and their macroscopic mechanical properties such as tensile strength and gel (Bloom) strength. Moreover, the findings of this study can help the scientists, in, e.g., art conservation and restoration, to predict the mechanical performance of these adhesives by performing a less material demanding and nondestructive physical measurement such as XRD.

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Covered tightly by a thin leather skin, three early seventeenth-century cornetts from the collection of the Rijksmuseum were examined with the focus on their construction and manufacturing. One cornett of the three unexpectedly turned out to have a peculiar construction and to be made out of two sections of different wood species. The question arose whether this could be original or is the result of an extensive restoration.As the internal structure is not accessible for analysis and examination, multi-scale Computed Tomography (CT) scanning was employed to identify the exact regions of interest (ROI) and subsequently perform scans at a sufficiently high resolution in those areas. 3D images of the hollow spaces such as the tunnelling structure caused by the common furniture beetle (Anobium punctatum) criss-crossing the wood species could be computed from the 3D x-ray tomography reconstruction. This allowed to place the occurrence of the insect infestation after the joining of the two sections. Fine tool-marks, signs of construction and potential indications of earlier treatments could be visualized. These results were compared with the other two instruments of the same group and cross-referenced to instruments in other collections, in an attempt to answer questions about the instrument’s authenticity and originality. While the unusual construction out of two wood species might be the result of an extensive repair, another possible hypothesis—based on the combination of the results—is that this unique choice of original manufacturing was intentional, possibly to avoid splitting of the wood when inserting the mouthpiece or to counteract undesired vibrations when played.

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This paper describes the investigation into the possibilities of removing non-original coatings on a Dutch late seventeenth-century lacquer cabinet. The secondary coatings show various degradation phenomena such as alligatoring, discolouration and craquelure, which have significantly changed the appearance of the original decoration. The aim was to find out if the degraded secondary coatings could be removed whilst preserving the original layers and to choose the most suitable method. Practical tests were carried out to remove thick oil-resin varnish from dammar varnish. The dammar varnish, also a secondary layer, was preserved because it retained good optical properties and serves as a protection for the original layers. The most suitable method for removing the oil-resin varnish proved to be a buffered aqueous solution, modified with the enzyme Lipase type VII and applied in xanthan gum gel or Evolon®, in combination with binary solvent mixtures for removing the softened varnish and rinsing the surface. The visibility and aesthetic appearance of the original decoration increased significantly.

Rococo furniture decorated with fragments of Asian lacquer was highly fashionable in eighteenth-century France. The furniture's curvilinear designs forced cabinetmakers to manipulate flat lacquer elements so that they could be applied to a curved carcase. By removing material from the rear of lacquered wooden panels, they produced sheets of lacquered 'veneer' with enough flexibility to allow careful bending. Their application was usually limited to substrates that were straight or curved along only one axis. New evidence has revealed that cabinetmakers experimented with techniques allowing the use of lacquer veneer for decorating bombé furniture designs, characterized by curvatures along multiple axes. This article presents examples showing such strategies, found on a pair of corner cabinets from the J. Paul Getty Museum, Los Angeles (78.DA.119.1-2) and a commode from the Rijksmuseum Amsterdam, Netherlands (BK-16652). In all three instances, the bombé forms are covered with Chinese lacquer veneer harvested from different types of export lacquer objects. X-radiography showed that segments of the veneer were removed to facilitate its compound bending, effectively tailoring it to the curved substrate. In addition, cross-sections from samples of the corner cabinets show that the original substrate of the Chinese lacquer is leather. The cutting techniques differ on all three objects, indicating that cabinetmakers were still searching for the most effective methods.

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