Search Results (109)

Museums may acquire archaeological artefacts discovered by non-specialists or amateur archaeologists, holding the potential to promote the safeguarding of cultural heritage by integrating the local community in their activities. However, this also creates an opportunity for the fraudulent sale of modern forgeries presented as archaeological artefacts, resulting in the need for a critical assessment of the artefact’s authenticity prior to acquisition by the museum. In 2019, the regional museum in Cáceres (Spain) was offered the opportunity to acquire a Phoenician-Punic head pendant, allegedly discovered in the vicinity of the city. The artefact’s authenticity was assessed by traditional approaches, including typological analysis and analysis of manufacture technique, which raised doubts about its purported age. VP-SEM-EDS analysis of the chemical composition of the different glass portions comprising the pendant was used for non-invasive determination of glassmaking recipes, enabling the identification of glass components incompatible with known Iron Age glassmaking recipes from the Mediterranean. Further comparison with historical and modern glassmaking recipes allowed for the identification of the artefact as a recent forgery made from glasses employing modern colouring and opacifying techniques. Full article

Glass curators often question how their treatments affect the long-term stability of historical glass. While damp cotton swabs are commonly used to remove surface salts and dust, the use of water remains controversial, particularly for heavily altered glass, due to concerns about worsening hydration. This study investigates the effect of water rinsing on an unstable soda-lime glass altered for six months (monoliths) and fifteen months (powders) at 35 °C and 85% relative humidity. Samples were then rinsed with Milli-Q water at 20 °C or 50 °C, and the monolithic glass was subsequently subjected to an additional 15 months of alteration under the same conditions. The glass surface was characterized by optical and scanning electron microscopy (SEM) as well as Raman spectroscopy to identify the nature of the salts. The evolution of the hydrated layer was assessed using transmission FTIR, Raman and solid-state NMR spectroscopies, ToF-SIMS, and thermogravimetric analysis (TGA). The results show that rinsing effectively removes surface salts—primarily sodium carbonate—and induces structural changes in the hydrated layer, promoting silicate network polymerization. Upon resuming alteration, rinsed monolithic samples exhibit no further degradation after the additional 15 months of alteration. These findings offer promising insights for conservation practices and may help curators refining their treatment strategies for altered glass. Full article

This article describes the case of the personal items found in common graves dated between 1939 and 1956 after the Spanish Civil War (1936–1939), located in Paterna’s cemetery (Spain). It was important in this study to know the state of the conservation of the objects and to obtain clues about their origin and use just as in a forensic study. This would allow the moral restitution of the historical memory of the victims of the war conflict. The multi-technique strategy has included light and electron microscopy, infrared spectroscopy and X-ray diffraction. Materials of the early 20th century used in pencil sharpeners, glasses, cutlery, lighters, rings, and buttons or medications contained in small bottles and boxes have been identified and have enabled the lives of their owners to be reconstructed during their imprisonment and execution. All these objects exhibited a thin layer of adipocere, a well-known compound in forensic science formed during the decomposition of human and animal corpses. Interestingly, rare corrosion processes have been identified in two of the objects analyzed, which are linked to their proximity to the decomposing corpses of the deceased. Copper sulfides and/or sulfates have been identified in the lighter, and scholzite, a zinc and calcium phosphate, has been identified in the glasses. Full article

Community regeneration plays a pivotal role in creating human-centered spaces by transforming spatial configurations, enhancing multifunctional uses, and optimizing designs that promote sustainability and vibrancy. However, the influence of such regeneration on spatial vitality—particularly its spatial heterogeneity and nonlinear effects—remains insufficiently explored. This study presents a comprehensive framework that combines the Difference-in-Differences (DID) method with multiple socio-spatial correlated factors, including place agglomeration, individual agglomeration, and social perception, offering a systematic assessment of urban vitality and evaluating the impact of regeneration interventions. By leveraging street-level imagery to capture environmental changes pre- and post-regeneration, this research applies Gradient Boosting Decision Tree Regression (GBDT) to uncover nonlinear built environment dynamics affecting urban vitality. Empirical analysis from six districts in Suzhou reveals the following: (1) A pronounced increase in urban vitality is seen in core areas, while peripheral districts exhibit more moderate improvements, highlighting spatially uneven regeneration outcomes. (2) In historically significant areas such as Wuzhong, limited vitality gains underscore the complex interplay among historical preservation, spatial configurations, and urban development trajectories. (3) Furthermore, environmental transformations, including variations in sky visibility, nonprivate vehicles, architectural elements, and the introduction of glass-wall structures, exhibit nonlinear impacts with distinct threshold effects. This study advances the discourse on sustainable urban regeneration by proposing context-sensitive, data-driven assessment tools that reconcile heritage conservation with contemporary urban regeneration goals. It underscores the need for integrated, adaptive regeneration strategies that align with local conditions, historical contexts, and urban development trajectories, informing policies that promote green, inclusive, and digitally transformed cities. Full article

The refractive index is an important parameter for the restoration of historical cultural heritage and for non-destructive optical techniques. In this study, different mathematical models for lead glasses were assessed in order to analyze their feasibility to calculate the theoretical refractive index of the historical enamels in stained-glass windows. The models selected were those specifically developed for lead glasses: the Appen method (1949), the Fanderlik and Skrivan model (1972), and the Bonetti and Salvagno method (1983). The results of the mathematical methods were compared with the real values analyzed via ellipsometry. The historical enamels were determined on non-prepared samples, taking into account the Cauchy model in order to avoid damaging the historical pieces. We show that the measured refractive indices of the historical enamels (1.59–1.66) are higher than the values of the lead glasses in the literature (1.55–1.57). The PbO and B₂O₃ were the compounds that most influenced the value of the refractive index; nevertheless, the presence of metallic elements increased their value compared to pure lead glasses. In addition, the presence of a thin layer of grisaille on the historical enamels and the formation of alteration layers could also modify the real value of the refractive index. As far as theoretical calculations are concerned, the mathematical model of Bonetti and Salvagno (1983) seems to be the most accurate model for this material, with errors < 0.04 units. None of the three models work for glasses with >60% PbO, which is not common in cultural heritage. Full article

Following the re-opening of the Rasa Trulnang Tsuklhakhang, the central temple in Lhasa, all of the new images of Buddhas, bodhisattvas, and famous lamas were placed behind glass except for those in the sancta sanctorum, the “Jokhang”. When a pilgrim approaches the central figure, the Jowo Śākyamuni, she climbs a ladder on his right side, lays a ceremonial scarf across his lap, and then lays her head there, like a child seeking solace from her mother. A wealthy pilgrim might return in the late afternoon, when the temple is closed to visitors, to sponsor a regilding ceremony, in which the sponsor can spend up to an hour nearly alone with the Jowo watching his whole body be repainted in gold. Based on participant observation, pilgrimage guides, and verses of praise offered to the Jowo, this paper considers how the cult of the Jowo uses moments of private intimacy to bridge the distance, both physically and historically, between a devotee and the Buddha. Full article

Enrico Van Lint (Pisa, 1808–1884) was a very prolific photographer, active in Pisa in the 19th century where he had a prominent photographic atelier. He was a meticulous experimenter, investigating the evolving photographic activity of his historical period. While his early works included calotypes using Fox Talbot’s methods, he rapidly adopted the collodion processes, becoming one of the most important Italian photographers that used this technique. At the present time, a vast number of examples of the works from Van Lint’s ateliers are preserved and archived in Pisa, under the supervision of the Italian Ministry of Culture in the Photographic Archive of the “Soprintendenza Archeologia, Belle Arti e Paesaggio per le provincie di Pisa e Livorno” (SABAP). This collection is composed of positive prints as well as glass plate negatives, from both Van Lint himself and his colleagues. To this day, Van Lint’s collection has not been studied using analytical techniques, and the identification of the photographic processes involved in the preparation of the positive prints has relied exclusively on thorough observation by historians and conservators. This provides a unique occasion for a first study of Van Lint’s collection, using multiple non-invasive and non-destructive techniques (multispectral imaging, XRF, and FTIR) that can identify the photographic process used to make the positives, as well as highlight significant differences or degradation phenomena. In this preliminary work, we investigated a selection of ten positive prints, attributed to both Van Lint himself and later reproductions from the original glass negatives. The selected samples include prints previously classified as albumen prints and gelatin prints, displaying slight differences in conservation status as well as in print finish. This analytical approach allowed for a proper characterization of these Van Lint’s prints, improving the historical and conservation knowledge to implement the best preventive preservation actions in the near future. Full article

The initial nucleus of gemstones at the Natural History Museum of the University of Florence (Italy) is linked to the significant collection of the Medici family, who began it as early as the 15th century. The present research aims to study this collection in order to (1) comprehensively review the archival and catalogue information available; (2) identify the mineralogical species correctly; and (3) gather information on the potential provenance of the gem deposits. To address these objectives, fifty gems were investigated using entirely non-invasive methods, ensuring the preservation of the collection’s precious and historical value. All specimens underwent autoptic observation and micro-Raman analysis, while a selection was further examined using PIXE-PIGE to characterise their chemical composition, including trace elements. The gems were attributed to seven mineral species: emerald, topaz, grossular, cordierite, quartz, orthoclase, and tourmaline. One gem was identified as a fake, made of glass and likely produced in the 17th century. Twenty-nine of the historical attributions in the catalogue were found to be incorrect and were subsequently revised. In some cases, the trace elements and mineral inclusions identified in the gems enabled the determination of potential provenance deposits, which were then compared with the available archival information. Full article

Limestone has always been widely used in various sectors, thus having significant economic and environmental impacts. The quarrying process is, on the one hand, essential, but on the other, harmful to the environment and people’s health, therefore, the challenge is finding a balance. This review explores the multifaceted nature of limestone, a sedimentary rock predominantly composed of calcium carbonate. The formation of limestone, along with its various types and global occurrence, is discussed to provide a basic understanding. The diverse applications of limestone range from historical uses in ancient monuments to contemporary roles in cement production, plasticized polyvinyl chloride (PVC), and soda–lime glass. The discussion extends to post-mining solutions, showcasing successful rehabilitation and innovative repurposing of former quarries into useful infrastructures, wildlife habitats, and cultural spaces. This article draws attention to the importance of sustainable practices and technological developments to balance resource use with environmental conservation. Ultimately, it emphasizes the need for responsible limestone quarrying and proactive rehabilitation strategies to ensure that no permanent ecological problems will occur. Full article

This experimental study explores the possibility of using an existing Trombe wall as a space for year-round cultivation to increase building resource efficiency. To do so with the least cost to the building, a small 0.75 m²/5.45 m³ Trombe wall cavity space was retrofitted with shelves placed behind the glazing, additional ventilation, and a watering network to be able to grow 400 hydroponic Kratky basil plants in individual glass jars. Historical thermal observations made at the site over a year-long timespan were contrasted with the experimental readings. When fully equipped, the Trombe wall’s thermal mass increased by 51%, which had a balancing effect on the system, lowering the average daily thermal oscillations from 35.41 °C to 17.88 °C. The living plants and water have also had significant cooling (26.99 °C to 22.91 °C) and humidifying (39.88 to 47.74%) effects. The system’s energy efficiency, however, decreased from 26 to 18% (absorption) and from 85 to 46 (dissipation), lowering its energy contribution to the building by about 30%. The average plant’s lifespan within the Trombe wall was 46 days, with 15% of the specimens surpassing the 100-day mark. Over the course of a year, 20.55 kg of edible greens were grown in the Trombe wall. The experiment has shown that it is possible to grow the plants inside the Trombe wall cavity during the warmer half of the year, revealing many possible ways to improve the space’s comfort, yields, and energy efficiency. Full article

Amber glass has been produced since at least the 6th century BC. Its value derives from its ability to mimic natural amber and, later, from its ultraviolet filtering properties. Until the 19th century, amber glass was widely used for the storage of food and medicines because its protective properties had been empirically recognized. This study investigates historical methods of amber glass production by using glass recipes from four Portuguese arcana (1793–1975) and focusing on Fe-S and Fe-Mn chromophores. Five recipes were reproduced under controlled laboratory conditions, resulting in 21 experiments. Of these, only 10 produced amber glasses were with different shades. Chemical compositions were analysed by WDXRF, while DSC and dilatometry were used to assess thermal properties. Vickers hardness tests and UV–visible absorption spectroscopy provided insight into mechanical strength and chromophore presence. The study found that FeS amber glass was more difficult to produce than Fe-Mn amber glass, given the complex variables involved in the former, such as SO₃ volatility affecting the final product. Reproduction of historical recipes showed that, even without modern chemical knowledge, historical glassmakers developed practical, empirical methods for making amber glass. These findings contribute to a broader understanding of glass conservation and highlight the importance of historical glass recipes for the interpretation and conservation of glass objects. Full article

Phenylethynyl-terminated imide (PETI) oligomers are highly valued for their diverse applications in films, moldings, adhesives, and composite material matrices. PETIs can be synthesized at varying molecular weights, enabling the fine-tuning of their properties to meet specific application requirements. Upon thermal curing, these oligomers form super-rigid network structures that enhance solvent resistance, increase glass-transition temperatures, and improve elastic moduli. Their low molecular weights and melt viscosities further facilitate processing, making them particularly suitable for composites and adhesive bonding. This review examines recent advancements in developing ultra-high-temperature PETIs, focusing on their structure–processing–properties relationships. It begins with an overview of the historical background and key physicochemical characteristics of PETIs, followed by a detailed discussion of PETIs synthesized from monomers featuring noncoplanar configurations (including kink and cardo structures), fluorinated groups, flexible linkages, and liquid crystalline mesogenic structures. The review concludes by addressing current challenges in this research field and exploring potential future directions. Full article

Recent research conducted by Heritage Crafts, a prominent national advocacy organisation dedicated to preserving traditional heritage crafts in the UK, has unveiled a concerning trend: several traditional craft skills teeter on the edge of extinction within the UK. This revelation stems from the Heritage Crafts Red List of Endangered Crafts, an initiative which identifies crafts facing the risk of endangerment. In their recent 2023 publication, Heritage Crafts highlighted the distressing decline of cut and engraved glass craftsmanship in the UK, categorising and placing both brilliant cutting (as endangered) and copper wheel engraving (as critically endangered) on the Red List of Endangered Crafts in the UK. This means that these crafts pose the risk of not being actively practised. In December 2023, the alarming downturn of these crafts in the UK was explored and discussed during a conference held at Edinburgh College of Art (ECA), entitled Edo-Kiriko: The Art of Japanese Cut Crystal. This event explored the cross-cultural connection and exchange that exists between Scotland and Japan, drawing upon a rich historical exchange that saw the transmission of Western-style glassmaking from Scotland to Japan in the 1870s–1880s. It also details the more recent exchange that has been in place between Edinburgh College of Art (ECA) and the Horiguchi Kiriko glass studio in Tokyo, Japan. This modern-day exchange has seen the recent transmission of glass-cutting skills through a masterclass led by Toru Horiguchi at ECA. This paper presents this conference, introducing the invited speakers and creating a commentary on the proceedings and the plenary discussions that unfolded. Focus and discussion will be given to the factors that have contributed to the current decline of cut and engraved glassmaking in the UK and the possible measures that could be taken to support and safeguard this field. The final part of this paper will offer a reflection on the conference proceedings and will conclude by making an urgent call for the future of cut and engraved glass craftsmanship in the UK. It is hoped this paper will draw attention to the urgent need for support from education and funding bodies, to safeguard and protect these vital heritage crafts, which boast a rich history in the UK. Full article

Strong winds or typhoon disasters pose significant risks to historical buildings in many countries and regions. Although numerous researchers have discussed the damage caused by natural wind disasters, little attention has been paid to the potential impact of renovation and adaptive reuse strategies on the wind resistance performance of historical buildings—an avoidable human-induced factor. This study selected the representative ancestral hall building in Guangzhou, namely Lujiang Academy, for on-site investigation and Computational Fluid Dynamics (CFD) simulation analysis. It examined two renovation approaches: installing glass curtain walls around the courtyard and enclosing the top of the courtyard with a glass canopy. This study also assessed the roof wind pressure distribution in its unaltered state to evaluate the impact of different renovation strategies on roof wind load distribution. The results showed that installing glass curtain walls can effectively reduce the upward suction effect on the main hall roof, thereby improving its wind resistance performance. Conversely, enclosing the courtyard with a glass canopy may increase negative pressure on areas such as the eaves and corridor roofs, raising the risk of roof damage. This study systematically evaluated the renovation strategies for historical buildings, detailing the specific impacts of different retrofit measures on the wind resistance performance of building roofs. The methods and findings are significant not only for the renovation of ancestral hall heritage buildings in Guangzhou but also for providing practical scientific methods and technical strategies for the conservation and renovation of similar historical structures. This research demonstrates an effective approach to enhancing wind resistance and preventive protection for historical buildings. Full article

Cases of historical and contemporary social movements suggest that among activists, reading texts together is a valuable learning experience. However, less research exists on the specific texts youth activists seek out in their work and the role these texts play in shaping their understanding of themselves as activists. Drawing on Rudine Sims Bishop’s classic formulation of books as mirrors, windows, and sliding glass doors, this study explores the under-appreciated role texts may play in drawing young people to activism and shaping their identities as activists. Coupled with interview data from six youth activists engaged in the climate justice movement, survey data from 237 self-identifying youth activists suggest that the texts youth activists name as influential serve a “through the looking glass” function: they often reflect problematic aspects of the social world and one’s place within it, while also revealing new and aspirational roles readers might take on to address social problems. The texts the youth identified as influential were diverse; there were few commonalities among titles, underscoring the importance of ongoing access to a broad range of reading materials. Ultimately, findings suggest that texts work to bind together the various internal and external, micro, meso, and macro influences that collectively shape youth activists’ narratives of becoming. Full article