Polychrome painting, a defining decorative element of ancient Chinese wooden architecture, served both esthetic and protective purposes. During the Qing Dynasty, it was categorized into official and folk styles, with the latter characterized by greater flexibility and regional diversity, forming a distinct artistic tradition. This study focuses on the Bozhou theatrical stage, a National Key Cultural Relics Protection Unit that exemplifies the fusion of regional architectural traditions that combining Huizhou-style gable walls with a northern-style glazed tile roof. On-site assessment identified various forms of deterioration in the polychrome paintings, underscoring the need for material analysis to inform conservation. Integrating with multi-analytical techniques of OM, SEM-EDS, Raman, XRD, FT-IR, and THM-Py-GC/MS, the research reveals that the structure was built primarily from locally sourced Populus wood. The painting ground layer was prepared using traditional techniques such as Yima-Wuhui and Danpihui, with brick ash as the base material, reinforced by bast fibers and bound with organic additives including fermented animal blood, animal glue, and tung oil, reflecting the adaptation of official methods into folk practice. Pigment analysis distinguished between original mineral-based paints and later synthetic pigments, separating original work from subsequent documented and undocumented repainting. The detection of imported synthetic pigments further illustrates the material and cultural exchanges of the late Qing period. By clarifying material use and technical practices, this study advances the understanding of Qing folk architectural painting and provides a scientific basis for its ongoing conservation and restoration.
The study of the thigh guards (haidate) of the Japanese armour B54, preserved at the Armeria Reale of Turin, was conducted to deepen the understanding of the manufacturing techniques of the protective lamellae (kozane) and to support the artifact's conservation treatment. The applied multi-analytical campaign allowed us to affirm that the lamellae and the binding laces were made of leather covered with Japanese black lacquer (kuro-urushi) and that their front surface was gilded with leaf. Furthermore, thanks to bibliographic research and the experimental construction of the lamellae, it was possible to obtain important information on the different phases of traditional manufacturing, such as the preparation of the leather, the procedure, the materials and the tools necessary for lacquering with urushi and the leaf gilding technique.
Indigo carmine, a semi-synthetic blue dye encountered in historical textiles, poses conservation challenges due to its poor wash fastness and tendency to transfer during aqueous treatments. Textile fibers dyed with indigo carmine often exhibit color migration during conservation wet cleaning, complicating preservation efforts. Due to the nature of indigo carmine interactions with proteinaceous textile fibers, this study assessed the pH-dependence of the wash fastness of indigo carmine combined with absorbance spectroscopy as a simple identification technique, mostly to differentiate it from non-soluble and more stable blue dyes. First, the pH-dependent wash fastness of wool samples dyed with indigo carmine was assessed and compared to samples dyed with natural indigo and madder as a negative control. Wash fastness tests conducted using water adjusted to pH 4, 5, 7, and 8.5 revealed strong pH dependence for only indigo carmine, with minimal dye migration at acidic pH, some dye migration at neutral pH, and the highest degree of dye migration occurring at pH 8.5. pH-dependent microextraction tests were then conducted for few-fiber samples using sub-milliliter wash volumes, successfully detecting indigo carmine in both replica and historical samples. HPLC was used to confirm the presence or absence of indigo carmine in selected historical samples. We note that identification of indigo carmine could be complicated by the fiber's age, sample size, color, presence of a water-insoluble finish, or degradation. Overall, these findings contribute to the understanding of indigo carmine's behavior and provide guidance for historical dye identification and decision-making in textile conservation treatments.
By applying a systematic methodology with collaborative stakeholder engagement, the concept of 'green' is defined and contextualized within the field of cultural heritage conservation. The approach included examining the strategies used in other industries, an extensive review of published resources, semantic literature analysis, and the application of recognized frameworks to identify conservation's key impacts and associated green parameters. Alongside this research, focused and widespread inputs and feedback were sought to ensure relevance of the developed green conservation framework within any professional context, and its transparent legibility for applying into practice. Specific research, feedback results, and the final outcomes - the green conservation definition and 14 green parameters - are presented.
Large outdoor iron artifacts are vulnerable to environmental factors, and their conservation presents an enormous challenge. The Pujindu site is renowned for its large iron artifacts. The 'Qixing Column' iron columnar artifacts exhibit gradient corrosion from top to bottom, which may compromise their stability. In this study, the corrosion characteristics of iron columns and the soluble chlorine content in their environmental samples were analyzed using scanning electron microscopy-energy dispersive spectroscopy, Raman spectroscopy, X-ray diffraction, and ion chromatography. Elemental chlorine caused structural differences in the corrosion layer at various locations on the iron column. Furthermore, from the top to bottom of the iron column, the soluble chlorine content increased, leading to a deterioration in the stability of the corrosion layer. Groundwater was identified as the primary source of chloride contamination in the iron artifacts at the site through the analysis of environmental data. This investigation elucidates the gradient corrosion characteristics of large iron objects by chloride ions, underscores the critical role of groundwater in the deterioration of outdoor iron artifacts, and provides valuable insights for the development of targeted conservation strategies.
