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Patina formed on ancient glass holds potential to be a useful tool in determining the age of patina and to interpreting its formative environment climatically, pedogenically, hydrochemically and biologically. To date, its usefulness in this regard appears to have been underestimated. However, if patina is to be used as a reliable indicator of age and the environmental conditions underpinning its formation, there needs to be a systematic examination and understanding of its development under controlled laboratory conditions using various types of glass and with various climate types and soil types. As such, to calibrate and interpret the age of patina, processes of its development and products of its formation, we believe that it is useful to produce patina under varying experimental conditions in the laboratory. This paper focuses on the successful experimental development of patina on glass under controlled laboratory conditions and paves the way for further exploration of the rich resource of information that can result from such experimentation. We cannot produce in detail the full range of long‐term products of patination. [ABSTRACT FROM AUTHOR]

This study compares the surface patina of ancient tin rich bronze with pure hydrothermally synthesized SnO2 nanoparticles using various analytical techniques, including metallographic microscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and high-angle annular dark-field scanning transmission electron microscopy. The primary crystalline component of the patina consists of approximately 5 nm SnO2 nanoparticles, which closely resemble pure SnO2, indicating their comparability. Cu was also detected in the patina; however, it did not form crystalline structures. The X-ray diffraction results showed a shift in the patina's peak, suggesting the infiltration of Cu into the SnO2 lattice, which compromises its crystallinity. In comparison to synthetic SnO2, the X-ray photoelectron spectroscopy spectra of the patina revealed novel peaks corresponding to both Cu and O, indicating the presence of Cu−O−Sn bonding—a characteristic feature of type-I patina. This suggests that the primary structure of type-I patina consists of crystalline SnO2 nanoparticles, with a limited amount of Cu integrated into its lattice configuration. The concentration of Cu within the SnO2 crystal units is restricted, leading primarily to the formation of amorphous Cu2O in conjunction with Sn. The presence of Sn enhances the structural stability of Cu2O, facilitating its incorporation while inhibiting the crystallization of Cu2O. However, when the Sn concentration is insufficient, an inadequate Cu–O−Sn amorphous phase may form, allowing for the potential crystallization of Cu2O. [ABSTRACT FROM AUTHOR]

Abstract This study compares the surface patina of ancient tin rich bronze with pure hydrothermally synthesized SnO2 nanoparticles using various analytical techniques, including metallographic microscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and high-angle annular dark-field scanning transmission electron microscopy. The primary crystalline component of the patina consists of approximately 5 nm SnO2 nanoparticles, which closely resemble pure SnO2, indicating their comparability. Cu was also detected in the patina; however, it did not form crystalline structures. The X-ray diffraction results showed a shift in the patina’s peak, suggesting the infiltration of Cu into the SnO2 lattice, which compromises its crystallinity. In comparison to synthetic SnO2, the X-ray photoelectron spectroscopy spectra of the patina revealed novel peaks corresponding to both Cu and O, indicating the presence of Cu−O−Sn bonding—a characteristic feature of type-I patina. This suggests that the primary structure of type-I patina consists of crystalline SnO2 nanoparticles, with a limited amount of Cu integrated into its lattice configuration. The concentration of Cu within the SnO2 crystal units is restricted, leading primarily to the formation of amorphous Cu2O in conjunction with Sn. The presence of Sn enhances the structural stability of Cu2O, facilitating its incorporation while inhibiting the crystallization of Cu2O. However, when the Sn concentration is insufficient, an inadequate Cu–O−Sn amorphous phase may form, allowing for the potential crystallization of Cu2O.

AbstractThis research explores the detailed methods of upcycling, contrasting them with traditional linear design processes through autoethnographic documentation. By centering on a material-oriented view of reuse, the study uncovers how upcycling actively interacts with a material’s past, encompassing human imprints, temporality, fragmentation, and signs of aging. While commonly acknowledged as reuse of worn garments, upcycling can entail intricate interactions with historical remnants and weathered materials, including the challenges posed by aged material patina and its transient nature. The research challenges the prevailing upcycling literature’s limited dialogue of the nuanced complexities associated with working with aging materials, which instead often prioritizes consumer-driven goals within a circular remanufacturing context. Through practices like upcycling, which center on physical making and materials, we uncover insights and opportunities for impactful change often overlooked in traditional material processes, design planning, and manufacturing processes. [ABSTRACT FROM AUTHOR]

This work aims to illustrate difficulties in conservation and intervention with regard to Carlo Scarpa’s exposed reinforced concrete, which is characterised by unique formal features. The case study of the Brion Tomb (1969-78), designed by Carlo Scarpa (1906-1978), is exceptional for its monumental character, along with its designer’s desire to envisage its ageing, but not its deterioration, over time. In this sense, the almost exclusive use of reinforced concrete for the building and the choice of certain experimental technical solutions place this architectural complex within the general context of problems related to the restoration of contemporary architecture, due to the theoretical and operational difficulties in defining interventions for its conservation. The restoration of this complex, which was completed in 2020, was an extraordinary opportunity to reflect on the methods and limits of conservation work, and to update technical capabilities to the current state of the art.

Abstract Indoor investigations are commonly used to assess the causes and extent of damage to bronze artwork and cultural heritage items; however, these methods typically involve destructive sampling and outdoor bronze sculptures are typically heavy and large, hindering their transport. In this study, 16 contemporary bronze sculptures exposed to outdoor environments for a period exceeding 20 years were evaluated in-situ to develop a non-destructive prediction model that can identify types of corrosion and quantify the amount of corrosion on bronze sculptures that cannot be easily transported. The sculptures were classified into three groups according to their patina chromaticity, reflectivity, and chemical composition. The corrosion characteristics were found to be copper oxide and sulfide patinas. Chromaticity and reflectivity investigations revealed that the chemical composition changes of the patinas corresponded to the formation of corrosion products, thus showing a high potential for the identification of the type of corrosion. Portable XRF spectroscopy showed that the low error rate of Cu make its compositional behavior a good indicator in identifying the type of corrosion of sulfide and chloride patinas. Portable Raman spectroscopy was able to detect basic sulfides such as brochantite, antlerite, and cuprite. The corrosion types and corrosion products on the bronze sculptures could be identified using chromaticity and reflectivity, portable X-ray fluorescence, and portable Raman spectroscopy. The rapid insitu diagnosis of these corrosion attributes is expected to contribute to establishing conservation treatment plans in the future.

Indoor investigations are commonly used to assess the causes and extent of damage to bronze artwork and cultural heritage items; however, these methods typically involve destructive sampling and outdoor bronze sculptures are typically heavy and large, hindering their transport. In this study, 16 contemporary bronze sculptures exposed to outdoor environments for a period exceeding 20 years were evaluated in-situ to develop a non-destructive prediction model that can identify types of corrosion and quantify the amount of corrosion on bronze sculptures that cannot be easily transported. The sculptures were classified into three groups according to their patina chromaticity, reflectivity, and chemical composition. The corrosion characteristics were found to be copper oxide and sulfide patinas. Chromaticity and reflectivity investigations revealed that the chemical composition changes of the patinas corresponded to the formation of corrosion products, thus showing a high potential for the identification of the type of corrosion. Portable XRF spectroscopy showed that the low error rate of Cu make its compositional behavior a good indicator in identifying the type of corrosion of sulfide and chloride patinas. Portable Raman spectroscopy was able to detect basic sulfides such as brochantite, antlerite, and cuprite. The corrosion types and corrosion products on the bronze sculptures could be identified using chromaticity and reflectivity, portable X-ray fluorescence, and portable Raman spectroscopy. The rapid insitu diagnosis of these corrosion attributes is expected to contribute to establishing conservation treatment plans in the future. [ABSTRACT FROM AUTHOR]

Atmospheric pollutants in the air form acid rain which interacts with bronze surfaces exposed in urban outdoor environment. In this study, different types of patinas on bronze were investigated during and after 9 years of exposure to urban environment in moderately polluted continental city. Natural bronze patina and artificial brown sulphide, green chloride, and green–blue nitrate patinas were investigated. Visual assessment was carried out at defined periods. After 9 years of exposure, an electrochemical study was performed to investigate the electrochemical activity of the patinas in artificial urban rain. Additionally, the patinas were characterised using a variety of techniques, including metallographic examination, scanning electron microscopy/energy dispersive X-ray spectroscopy, Raman spectroscopy, X-ray diffraction analysis, X-ray-photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry to analyse the surface morphology, chemical composition, and stratigraphic features of the patinas. Evolution of the patinas was shown to be a result of both, the composition of the acid rain and the hydrophobicity of the patinated surfaces. [ABSTRACT FROM AUTHOR]

ÖZ: Arkeolojik sahtecilik, araştırmacıları, koleksiyoncuları veya kamuyu aldatmak amacıyla yapılan sahte eserler, yazıtlar veya diğer arkeolojik materyalleri ifade etmektedir. Sahtecilik, arkeoloji ve sanat tarihi dünyasında uzun süredir devam etmektedir. Sahte eserlerin tespit edilebilmesi arkeologlar, sanat tarihçileri, malzeme bilimcileri, dil bilimciler ve diğer uzmanlar arasındaki iş birliğini içeren çok disiplinli bir yaklaşım gerektirmektedir. Bu çalışmada eserlerin otantisitesi araştırmalarında uygulanacak malzeme karakterizasyonu ile ilişkili inceleme süreci önerilmektedir. Eserin tanımlanması farklı malzemelerin işlem/üretim zinciri (chaîne opératoire) içerisinde ve arkeolojik bilgi birikimi kapsamında değerlendirilmektedir. Arkeolojik buluntuların bu zincir içinde tanımlanması fiziksel, kimyasal, biçimsel ve estetik özelliklerinin daha iyi sınıflandırılmasını sağlamaktadır. Çalışmada, taş, pişmiş toprak ve metal hammaddeden yapılan arkeolojik eserlerin işlem zinciri bağlamında incelenmesinde kullanılan malzeme karakterizasyonu yöntemlerinden bahsedilmiştir. Ayrıca gerçekliği incelenen eserlerin patina tabakasının analizlerinin, bu tabakanın doğal ya da yapay olarak oluşması ile ilgili bilgi verdiği belirtirmiştir. Sonuç olarak arkeolojik buluntuların malzeme analizlerinin detaylı olarak değerlendirilmesinin, sahte eserlerin belirlenmesi sırasında karşılaştırma için veri sağlaması bakımından önemi vurgulanmıştır. Ayrıca çalışmada RGB ve CIE XYZ renk analizi yöntemleri ile gerçek eserlerden elde edilen ölçümler ile oluşturulacak bir veri bankası ileride çok daha kısa zamanda ve az maliyetli olarak ön değerlendirme yapılmasına olanak sağlayacağı önerilmiştir. ABSTRACT: Archaeological forgery refers to forged artifacts, inscriptions, or other archaeological material made with the intent to deceive researchers, collectors, or the public. Forgery has long existed in the world of archeology and art history. Identifying counterfeit artifacts requires a multidisciplinary approach that includes collaboration between archaeologists, art historians, materials scientists, linguists, and other experts. In this study, a process related to the material characterization to be applied in the research of the authenticity of the works is suggested. The identification of the artifact is evaluated within the chaîne opératoire of various materials. The identification of archaeological finds in this chain provides a better classification of their physical, chemical, formal, and aesthetic features. In the study, material characterization methods used in the analysis of archaeological artifacts made of stone, terracotta, and metal raw materials in the context of the process chain are mentioned. It is also stated that the analysis of the patina layer of the works whose authenticity was examined gives information about the natural or artificial formation of this layer. As a result, the importance of detailed evaluation of material analysis of archaeological finds is emphasized in terms of providing data for comparison during the identification of counterfeit artifacts. In addition, it has been suggested in the study that a database to be created with measurements obtained from real works with RGB and CIE XYZ color analysis methods will allow preliminary evaluation in a much shorter time and with less cost in the future.

Chinese ancient bronze fragments from three periods of history were investigated in terms of the characteristics of substrate and patina. The non-destructive protective effect of menthol coating was verified. Patinas on the fragments of the Spring and Autumn period, Warring State period, and Han Dynasty all contain the major components CuCl2·3Cu(OH)2 and Cu2(OH)2CO3. The residual components, some oxides and chlorides of Pb and Sn, show no evident distribution trend in the patinas except PbCl2 is segregated beneath the patina of the Han dynasty fragment. Menthol coating shows a consistently protective ability for these patinated fragments. However, its sublimation is strongly affected by ambient temperature and relative humidity (RH). Menthol coating with an initial thickness of ∼500 µm could effectively protect the fragments for 328 h under 23 ℃ with 54% RH while for only 42 and 2 h respectively under 25 ℃with 100% RH and 35 ℃ with 100% RH.

Paolo Marconi no fue el primero en señalar la importancia de recuperar el uso de las técnicas y materiales tradicionales en la restauración, pero sí uno de sus mejores y más coherentes defensores. A lo largo de una dilatada trayectoria profesional las fue estudiando y empleando con creciente conocimiento de causa. Se valió para ello del trabajo a pie de obra, del diálogo con los artífices y de la investigación documental. De su largo proceso de aprendizaje no solo dejó constancia en sus libros y artículos, sino también en obras colectivas como los manuali del recupero de Roma y Palermo, los cuales constituyen una apuesta por recuperar y transmitir el conocimiento constructivo peculiar de cada región o ciudad de Italia.

The article deals with a small bulla of unknown provenance that was purchased some forty years ago in the Bedouin market of Beʾer Sheva. The bulla was stamped with a seal depicting a roaring lion, above which the letters (LSM[Ꜥ]) were straightforwardly identified; it closely resembles the famous 'ShemaꜤ servant of Jeroboam' seal from Megiddo. Significantly, this unique bulla represents, to date, the first example of an ancient bulla stamped with a scaled-down authentic seal of a known master-seal of the Iron Age in Israel. The authenticity of the bulla was confirmed by meticulous laboratory tests, verifying both that it is genuine and that its date coincides with that of the ShemaꜤ seal from Megiddo. [ABSTRACT FROM AUTHOR]

Archaeological forgery refers to forged artifacts, inscriptions, or other archaeological material made with the intent to deceive researchers, collectors, or the public. Forgery has long existed in the world of archeology and art history. Identifying counterfeit artifacts requires a multidisciplinary approach that includes collaboration between archaeologists, art historians, materials scientists, linguists, and other experts. In this study, a process related to the material characterization to be applied in the research of the authenticity of the works is suggested. The identification of the artifact is evaluated within the chaîne opératoire of various materials. The identification of archaeological finds in this chain provides a better classification of their physical, chemical, formal, and aesthetic features. In the study, material characterization methods used in the analysis of archaeological artifacts made of stone, terracotta, and metal raw materials in the context of the process chain are mentioned. It is also stated that the analysis of the patina layer of the works whose authenticity was examined gives information about the natural or artificial formation of this layer. As a result, the importance of detailed evaluation of material analysis of archaeological finds is emphasized in terms of providing data for comparison during the identification of counterfeit artifacts. In addition, it has been suggested in the study that a database to be created with measurements obtained from real works with RGB and CIE XYZ color analysis methods will allow preliminary evaluation in a much shorter time and with less cost in the future. [ABSTRACT FROM AUTHOR]

The growth of patinas on artistic or archeological copper alloys is a determining stage to reproduce similar surface conditions such as corrosion protection of cultural heritage materials. In this work, the kinetic growth and protective properties of the corrosion products layer of a quaternary copper alloy have been characterized using linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy‐EDS, atomic force microscopy, X‐ray diffraction, and Raman spectroscopy. The results of LSV show that the patina formation is a mixed process consisting of dissolution and direct film formation. EIS results show that the kinetic formation modifies the characteristics of the corrosion layer allowing a Warburg‐like diffusive mechanism or the response of a porous oxide layer without diffusive phenomena. The roughness and thickness of the patina enhance with the decrease in the scan rate. The patina is mainly composed of copper and tin corrosion products. [ABSTRACT FROM AUTHOR]

Copper trihydroxychlorides, which are known as "bronze disease", are dangerous corrosion products that compromise the stability and conservation of bronze sculptures. Here, we performed artificial patina corrosion experiments on quaternary bronze (Cu-Zn-Sn-Pb) to examine the corrosion behavior of the chloride patina commonly found in bronze objects in marine environments. The chromaticity and reflectance of the patina in the context of the corrosion products indicate that copper trihydroxychloride, which is commonly found in a single color in marine environments, was produced early in the corrosion experiment. Furthermore, the corrosion of bronze had different effects on the alloying elements, contrary to pure copper corrosion. The chloride patina formed a single patina layer of copper trihydroxychlorides. This patina layer was divided into the outer porous powder and inner uniform layers. Furthermore, the interaction of oxygen in the atmosphere with the corrosion layer and internal oxidation of tin in the alloy promoted powdering. These results provide important basic data for research on sculpture conservation and corrosion characteristics, such as changes in color, chemical composition, and corrosion products on the patina surfaces of outdoor bronze sculptures. [ABSTRACT FROM AUTHOR]

This work examines the possibility of acrylic waterborne coating application in the protection of bronze cultural heritage. In order to enhance the coating protective properties, the surface pretreatment with long-chain phosphonic acid is investigated. Studies are conducted on bronze, either bare or covered by two types of patina, by using polarization measurements and electrochemical impedance spectroscopy during 3 weeks of continuous immersion in simulated urban acid rain solution. The role of 12-aminododecylphosphonic acid as corrosion inhibitor and adhesion promoter is studied. The results obtained within this research show that the corrosion protection by the waterborne coating increases in time in all cases and it is enhanced by the phosphonic acid pretreatment. The greatest impact of studied pretreatment on the overall corrosion protection level is observed on bare bronze substrate. [ABSTRACT FROM AUTHOR]

Yellow patina formed on the stone surfaces of historical buildings, monuments, and archaeological structures due to weathering is considered a value of the building in the conservation of cultural heritage studies. Although yellow patina layers can be easily distinguished on white marble surfaces, it is not possible to distinguish them on the yellow travertine surfaces with the naked eye. It should be taken into account in yellow travertines as well as marble surfaces before conservation treatments of the stone. In this study, mineralogical and chemical compositions and the thicknesses of yellow patina layers formed on yellow travertine and marble surfaces in Aizanoi, Aphrodisias, and Hierapolis archaeological sites in Turkey were analyzed in order to constitute a conservation approach in the archaeological sites. In this respect, XRD, FT-IR, SEM-EDX, and LIBS were used in the determination of compositions and thicknesses of yellow patina. Although LIBS analysis is a more convenient method to investigate patina layers on stone surfaces, this technique is not as well known as the others. Yellow patina layers contained calcium oxalate in the form of whewellite (CaC2O4.H2O). Their thicknesses were between 15 and 100 μm and should be protective against weathering on travertine and marble surfaces. LIBS analysis seems to be the most convenient micro-destructive method to estimate the thickness of the yellow patina layers on the marble and yellow travertine surfaces. The determination of the thickness of the yellow patina is critical to keep irreversible cleaning interventions, especially for the yellow travertines due to their similar colors. Yellow patina is mainly composed of calcium oxalate with clay minerals and organic compounds. [ABSTRACT FROM AUTHOR]

This work describes experimental results concerning the chemical composition of the alloy patina and inlays from the medieval copper alloy door of the cathedral of Troia (southern Italy), dating back to 1127 CE. The analyses were conducted in situ with no sampling or sample preparation required, using a portable energy-dispersive X-ray fluorescence (ED-XRF) instrument. The compositional results show that the two door leaves were made using a binary alloy of copper and lead, while the nails, lion protomes, and handles have a different chemical composition. Moreover, the analyses revealed uniform concentrations of chlorine, probably due to cleaning treatments during the restoration. It is important to emphasise that the obtained results are the only ones related to this valuable masterpiece analysed.

Copper alloys interact with air pollutants to form corrosion products and, consequently, a patina on outdoor bronze sculptures. In this study, corrosion experiments were conducted to clarify the corrosion behaviors of artificial sulfide patina in an urban–industrial environment on a quaternary bronze alloy (Cu–Zn–Sn–Pb) with a composition and metallurgical properties similar to those of outdoor bronze sculptures. The correlation between the chromaticity and reflectance of the patina revealed increasing brochantite with the corrosion of the patina and an association between the chromaticity a* and patina growth. Cuprite and brochantite were distinguished, and the point at which brochantite covered the patina surface was determined. The quantitative changes in brochantite were mainly influenced by physical causes such as the crystal size and patina layer thickness as well as by Cu2+ ions working as color formation ions moving to the outermost layer. Atmospheric corrosion of the alloy resulted in reduced Cu and Zn contents and increased Sn and Pb contents. The patina consisted of brochantite in the outermost layer and cuprite and cassiterite in the inner layers. These findings should clarify corrosion characteristics such as the surface color, composition, and changes in corrosion products of outdoor bronze sculptures and contribute toward their preservation. [ABSTRACT FROM AUTHOR]

This work describes experimental results concerning the chemical composition of the alloy patina and inlays from the medieval copper alloy door of the cathedral of Troia (southern Italy), dating back to 1127 CE. The analyses were conducted in situ with no sampling or sample preparation required, using a portable energy-dispersive X-ray fluorescence (ED-XRF) instrument. The compositional results show that the two door leaves were made using a binary alloy of copper and lead, while the nails, lion protomes, and handles have a different chemical composition. Moreover, the analyses revealed uniform concentrations of chlorine, probably due to cleaning treatments during the restoration. It is important to emphasise that the obtained results are the only ones related to this valuable masterpiece analysed. [ABSTRACT FROM AUTHOR]

Microscopic observation correlated with chemical–mineralogical characterization was performed on pigment samples from "Abrigo del Lince" rock art site (V-IV millennium BC), in order to provide contributions to the study of prehistoric schematic art on granite in the province of Badajoz (Spain). The research objectives include the understanding of technological and cultural aspects, as well as of conservation and deterioration issues related to the pictographs. The multi-analytical approach encompasses the integration of microscopic observation, SEM–EDS analysis, micro-Raman spectroscopy, and ATR-FTIR and allowed to achieve a multispectral overview of the samples and to describe their varied composition and the alteration pattern which connects them. The main phases overlying the granitic bedrock and involved in this sequence are as follows: hematite, whewellite, and gypsum. While hematite could be stratigraphically considered the most ancient layer and assigned to the use of red ochre as a pigment, whewellite and gypsum are the main constituent of the alteration layer which forms a patina over the pictographs, due to weathering processes. Finally, the role of biofilms in rock art conservation is discussed, suggesting that, especially for what concern thin and homogenous layers of oxalates, their presence should not be necessarily considered an issue. [ABSTRACT FROM AUTHOR]

The bronze patina is aesthetically pleasing and enhances the corrosion resistance of the metallic object. This corrosion product layer can develop naturally, through aging or artificially. However, artificial methods require substances that are hazardous to human health and the environment. In this study, a sustainable approach to patina development, based on the anodic polarization of a 85.5Cu-4.2Pb-4.5Sn-5.7Zn copper alloy immersed in 0.1 M NaCl + 0.01 M NaHCO3 were characterized using polarization curves, chronoamperometry, electrochemical impedance spectroscopy, electrochemical noise measurements, X-ray diffraction, and scanning electron microscopy. The results indicate that the anodic potential modifies the current density as well as the diffusion coefficient of oxygen associated with a thicker corrosion product layer. Electrochemical Impedance spectroscopy and electrochemical noise show that the porous behaviour and corrosion resistance increases as the potential becomes more anodic due to the formation of a protective layer. This behaviour corresponded with the results acquired by chronoamperometry. The surface characterization shows that the potential applied changes the surface morphology and composition of the corrosion products, being identified the crystalline phases of nantokite and atacamite although Cu, Cl, O, Zn, and Pb elements were also detected. [ABSTRACT FROM AUTHOR]

Abstract Murujuga in Western Australia has the largest concentration of ancient rock engravings (petroglyphs) in the world. However, the Murujuga rock art is potentially threatened by local industrial air pollution, in particular by acid rain, but unambiguous scientific evidence is still missing. Here, we report on results of an accelerated weathering experiment, simulating Murujuga weather and climate conditions that was designed and performed to test whether the expected small changes in chemical, mineralogical, and physical characteristics of the rock surface can be detected and reliably quantified by various analytical means. Locally acquired Murujuga granophyre and gabbro samples with natural varnish were artificially weathered for up to four months in a climate chamber under conditions that simulated 2 years of natural weathering. Mineralogical, chemical, and physical changes were qualitatively monitored by X-ray diffraction and confocal Raman spectroscopy, and quantified by colorimetry, portable X-ray fluorescence spectrometry, and micro-computed tomography. In addition, artificial rainwater that was sprinkled over the rock samples was collected and analysed by inductively-coupled plasma mass spectrometry. The results show significant chemical and physical changes of the surfaces of the rock varnish after 1 month of artificial weathering. The analytical results demonstrate that it is possible to quantitatively monitor small changes caused by the weathering of gabbro and granophyre. Therefore, such a semi-actualistic experimental approach, when carefully designed, potentially allows testing the hypothesis that the weathering rate of the Murujuga petroglyphs is increased by local industrial air pollution. Further experimental work is currently under way.

This study assessed the atmospheric corrosion resistance of seven steel alloys, four custom-made and three commercially available, installed on a sheltered location on a bridge in Ontario-Canada. Visual inspection, SEM/EDS, thickness and weight gain measurement and electrochemical techniques were employed to investigate the protectiveness of patina. Results showed that small quantities of Cr, Mo, and P did not significantly improve the patina. Ni was effective, but the combination of Nb and B was crucial for enhancing it. Additionally, a linear correlation of average patina thickness and weight gain was observed for the alloys in this study. • Corrosion resistance of seven steel alloys, installed on a sheltered location on a bridge in Ontario, Canada, were studied after 10 years. • Cr, Mo, and P in small quantities did not significantly enhance the patina, Ni was effective. Combination of Nb and B improved patina's performance. • For sheltered locations, a linear correlation between patina thickness and corrosion weight gain was observed. [ABSTRACT FROM AUTHOR]

The corrosion behaviors of four ternary Cu-Sn-Pb alloys with varying tin contents were investigated to determine the impact of tin content on the photo-induced corrosion of bronze. Photo-induced passivation, which effectively inhibits corrosion, was observed in all the investigated Cu-Sn-Pb alloys, even those with relatively low tin content, and a possible mechanism was proposed. Based on these findings, photo-induced passivation treatment was applied to two types of artificially patinated bronzes, achieving inhibition efficiencies of up to 82 % and 93 %. This method offers a novel corrosion mitigation strategy for bronze artifacts, capable of avoiding contamination of archaeological artifacts by foreign substances. • UV illumination inhibits bronze corrosion across varying tin contents by promoting the formation of a compact SnO 2 layer. • A substantial Sn enrichment within the patina layer favors the formation of this compact oxide film more readily. • The oxide films on high-tin bronzes exhibit greater photostability compared with low-tin bronzes. • Photo-induced passivation treatment can mitigate the corrosion of patinated bronzes without introducing foreign substances. [ABSTRACT FROM AUTHOR]

The aim of this work was to examine corrosion behaviour of bare and artificial patinated bronzes during exposure to urban outdoor atmosphere. Studies were conducted on copper and two different bronzes in order to evaluate the influence of substrate composition on patina composition and electrochemical behaviour. Additionally, two different patination methods were compared. Corrosion behaviour was examined using electrochemical impedance spectroscopy with gel-electrolyte electrochemical cell. The composition of patina was determined by ATR-FTIR spectroscopy. The obtained results showed that all studied artificial patinas initially decrease the corrosion resistance of copper and bronzes but in time their corrosion resistance improves, and even for certain combinations, artificial patina-bronze corrosion resistance is higher than that of naturally patinated bronze.

Copper alloys interact with air pollutants to form corrosion products and, consequently, a patina on outdoor bronze sculptures. In this study, corrosion experiments were conducted to clarify the corrosion behaviors of artificial sulfide patina in an urban–industrial environment on a quaternary bronze alloy (Cu–Zn–Sn–Pb) with a composition and metallurgical properties similar to those of outdoor bronze sculptures. The correlation between the chromaticity and reflectance of the patina revealed increasing brochantite with the corrosion of the patina and an association between the chromaticity a* and patina growth. Cuprite and brochantite were distinguished, and the point at which brochantite covered the patina surface was determined. The quantitative changes in brochantite were mainly influenced by physical causes such as the crystal size and patina layer thickness as well as by Cu2+ ions working as color formation ions moving to the outermost layer. Atmospheric corrosion of the alloy resulted in reduced Cu and Zn contents and increased Sn and Pb contents. The patina consisted of brochantite in the outermost layer and cuprite and cassiterite in the inner layers. These findings should clarify corrosion characteristics such as the surface color, composition, and changes in corrosion products of outdoor bronze sculptures and contribute toward their preservation.

Murujuga in Western Australia has the largest concentration of ancient rock engravings (petroglyphs) in the world. However, the Murujuga rock art is potentially threatened by local industrial air pollution, in particular by acid rain, but unambiguous scientific evidence is still missing. Here, we report on results of an accelerated weathering experiment, simulating Murujuga weather and climate conditions that was designed and performed to test whether the expected small changes in chemical, mineralogical, and physical characteristics of the rock surface can be detected and reliably quantified by various analytical means. Locally acquired Murujuga granophyre and gabbro samples with natural varnish were artificially weathered for up to four months in a climate chamber under conditions that simulated 2 years of natural weathering. Mineralogical, chemical, and physical changes were qualitatively monitored by X-ray diffraction and confocal Raman spectroscopy, and quantified by colorimetry, portable X-ray fluorescence spectrometry, and micro-computed tomography. In addition, artificial rainwater that was sprinkled over the rock samples was collected and analysed by inductively-coupled plasma mass spectrometry. The results show significant chemical and physical changes of the surfaces of the rock varnish after 1 month of artificial weathering. The analytical results demonstrate that it is possible to quantitatively monitor small changes caused by the weathering of gabbro and granophyre. Therefore, such a semi-actualistic experimental approach, when carefully designed, potentially allows testing the hypothesis that the weathering rate of the Murujuga petroglyphs is increased by local industrial air pollution. Further experimental work is currently under way. [ABSTRACT FROM AUTHOR]

Abstract A bronze kettle dating from the 1st to 2nd century was found in a riverbed of the Kupa river in Croatia. After excavation it spent another 50 years in a depot of a museum in atmospheric conditions prior to starting the conservation treatment and our studies. A study on the surface layers development was performed to determine the whereabouts of the object through its history. This study is a demonstration of how such analysis can be used to reconstruct what the object went through during its life span. Samples taken from the kettle were observed by optical and scanning electron microscopy (SEM), and analysed by X-ray fluorescence (XRF), X-ray energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR). It was determined that the kettle is made of low-tin bronze, with low amounts of iron, aluminium, calcium and nickel. While being in the riverbed malachite formed on the kettle. After longer exposure to the river Si-oxides and CaCO3 formed on the surface of the kettle, over malachite. It was shown that the kettle probably had a ferrous alloy handle which degraded and disappeared in time. After excavation, the kettle came again in an oxygen-enriched atmosphere and formed new surface layers over the malachite layer. As the museum the kettle has been kept in since excavation is set in a highly industrial area sulphur compounds have been formed on the surface.

In the present paper, we would like to discuss results of a preliminary field research in the vicinity of the chocolate flint outcrops in Iłża, Site 3, “Krzemieniec I” (Kielce Upland, southeastern Poland), including the discovered lithic finds – debitage products (flakes and blades), cores, and formal tools, such as bifacial knives. We made an attempt to infer the chronology of those lithic specimens which were found during the surface survey or in trenches without preserved stratigraphy. Based on their spatial distribution, as well as typological and technological analysis, we distinguished the oldest traces of occupational activities of prehistoric societies in the vicinity of Iłża related to the Middle and Upper Palaeolithic. Additionally, we conducted a microscopic analysis of the state of preservation of characteristic lithic artefacts. This showed possibilities of linking specific states of preservation of flint surfaces with a generalised chronology of the Stone Age and Bronze Age. [ABSTRACT FROM AUTHOR]

This article examines how notions of patina are conveyed by experts in the antiques trade. How do antiques experts convey perceptions of patina to their clients and audience? How do they explain, persuade, and put forward their standards of condition? Three examples are analysed, a conversation about a sundial from the Swedish Antiques Roadshow, a conversation about a toy car from the British Antiques Roadshow and a vintage watches collecting guide from Christie's auction house. Different persuasive strategies and styles used by the experts to convey their norms are identified. A change towards higher appreciation of patina can be discerned. Furthermore, the article analyses patina in regard to the relationship between surface and core of an object and in regard to use and usefulness. It is suggested that objects with patina are popular because we as humans feel an affinity with them. If things have a life trajectory, it will also involve ageing, and by surrounding ourselves with old, imperfect things we can come to terms with our own ageing process.

The aim of this work was to examine corrosion behaviour of bare and artificial patinated bronzes during exposure to urban outdoor atmosphere. Studies were conducted on copper and two different bronzes in order to evaluate the influence of substrate composition on patina composition and electrochemical behaviour. Additionally, two different patination methods were compared. Corrosion behaviour was examined using electrochemical impedance spectroscopy with gel-electrolyte electrochemical cell. The composition of patina was determined by ATR-FTIR spectroscopy. The obtained results showed that all studied artificial patinas initially decrease the corrosion resistance of copper and bronzes but in time their corrosion resistance improves, and even for certain combinations, artificial patina-bronze corrosion resistance is higher than that of naturally patinated bronze. [ABSTRACT FROM AUTHOR]

"The architecture of Markus Wespi, Jérôme de Meuron and Luca Romeo generally seeks a close connection to its surroundings and the local building culture; the architects look for clues in the existing culture and tradition. They are interested in the combination of traditional and modern elements, which together form a new unity and push the historical development forward. In their projects, they seek to achieve a certain timelessness; the combination of traditional materials with new elements creates a natural self-evidence that integrates the familiar and the new, thus being able to continue to develop and survive in the future. In mountainous and sloping locations, buildings have an enormous impact on the landscape and should therefore be integrated carefully with it in both form and materials, rather than simply benefitting from it thanks to large viewing windows. We like the concept of a new building which seems to have been there for a long time, whose natural materials have developed a patina which makes them even more beautiful. We are particularly fascinated by its atmosphere, light and shadow."

A bronze kettle dating from the 1st to 2nd century was found in a riverbed of the Kupa river in Croatia. After excavation it spent another 50 years in a depot of a museum in atmospheric conditions prior to starting the conservation treatment and our studies. A study on the surface layers development was performed to determine the whereabouts of the object through its history. This study is a demonstration of how such analysis can be used to reconstruct what the object went through during its life span. Samples taken from the kettle were observed by optical and scanning electron microscopy (SEM), and analysed by X-ray fluorescence (XRF), X-ray energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR). It was determined that the kettle is made of low-tin bronze, with low amounts of iron, aluminium, calcium and nickel. While being in the riverbed malachite formed on the kettle. After longer exposure to the river Si-oxides and CaCO3 formed on the surface of the kettle, over malachite. It was shown that the kettle probably had a ferrous alloy handle which degraded and disappeared in time. After excavation, the kettle came again in an oxygen-enriched atmosphere and formed new surface layers over the malachite layer. As the museum the kettle has been kept in since excavation is set in a highly industrial area sulphur compounds have been formed on the surface. [ABSTRACT FROM AUTHOR]

This article focuses on a case of failed consecration: the Egyptian obelisk in New York's Central Park, commonly known as Cleopatra's Needle. The obelisk arrived in New York from Alexandria in 1880, with great fanfare. For a brief period, it was the talk of the town: a tourist curiosity and star of advertising campaigns for consumer goods. After an initial surge in public visibility, the monument's prominence faded. Today, the obelisk is not on the list of New York's top cultural attractions, and no longer features in media campaigns or political rallies. I ask why the obelisk's initial popularity failed to crystallize into an enduring condition of consecration. To answer this question, I use archival data to chart the obelisk's transfer of ownership and planned move, through its Central Park début and subsequent decline in cultural salience. The obelisk met key criteria associated with successful cases of retrospective consecration. What weakened the obelisk's career were lack of consecrating institutions and inherently unstable material conditions. These mechanisms are symbiotically related: because no institution took responsibility for conserving and protecting the obelisk, its granite face rapidly deteriorated and frustrated attempts to attract potential consecrating institutions. The article makes a twofold contribution to the literature on retrospective consecration. First, by discussing a failed case, it highlights the linked efficacy of consecration formation mechanisms. Second, in focusing on an ancient monument, it demonstrates the role played by materials and the specific measures of consecration that obtain in the broader sphere of ancient monuments. [ABSTRACT FROM AUTHOR]

This article focuses on an antique wooden fragment from Easter Island engraved with a single rongorongo (RR) glyph. Based on our analysis, we conclude that the most likely hypothesis regarding this fragment is that it dates to pre-missionary times (prior to 1864) and was part of some type of weapon or fighting instrument, either of a functional or ritual nature. It may represent a portion of a handle for an obsidian-tipped spear or knife. The "bird"-like RR glyph on the fragment belongs in all probability to a category that has previously been connected in the scholarly literature on RR with "slumber", and hence "waning", "demise", and "death". Its presence on a hand-weapon or ceremonial warlike artifact suggests a meaningful real-world, "non-literary", context for this glyph. [ABSTRACT FROM AUTHOR]

There is a lack of research on people’s psychological perceptions to decay or patina that is part of the historic environment. Built heritage conservation doctrine and law are based on the assumption that all people have a similar, positive aesthetic perception to patina in the built environment, although there are very few empirical studies that have attempted to confirm or challenge this assumption. This study is based on the statistical analysis of survey data from 864 people in the United States who ranked 24 images of old, decayed building materials and 7 control images of new building materials based on aesthetic qualities, condition, and perceived age. The results indicate that people do not like decayed earthen building materials, concrete, or ferrous metals and have a neutral opinion of the aesthetic qualities of aged brick, preferring new brick as well as aged wood. While there are small differences based on race, ethnicity, and gender, the largest difference in responses is between people who work in the historic preservation/CRM field and those who do not. This finding appears to indicate that people who work in these fields have a different psychological response to decay/patina in the built environment than laypeople, which has important ramifications in terms of decision-making processes regarding interventions in the older built environment.

Designated to “stay” in time and to “contrast” time – the former referred to the chronological meaning, the latter to the meteorological one – the life of buildings sometimes addresses the relationship with their pre-existences through variations linked to time. The essay aims at unfolding this phenomenon in the architecture of Álvaro Siza Vieira, proving his special ability to control the metamorphoses of the built matter. Complementing critical research with the dialogue established with the Portuguese master, the analysis of the evolutive process of some of his works demonstrates how time – intended as “the other architect”, which overlaps and opposes its own action to the one carried out by the builder – does not seem to counteract the experience of Siza but rather enhances the embedding of architecture in the site.

Designated to "stay" in time and to "contrast" time - the former referred to the chronological meaning, the latter to the meteorological one - the life of buildings sometimes addresses the relationship with their pre-existences through variations linked to time. The essay aims at unfolding this phenomenon in the architecture of Alvaro Siza Vieira, proving his special ability to control the metamorphoses of the built matter. Complementing critical research with the dialogue established with the Portuguese master, the analysis of the evolutive process of some of his works demonstrates how time - intended as "the other architect", which overlaps and opposes its own action to the one carried out by the builder - does not seem to counteract the experience of Siza but rather enhances the embedding of architecture in the site. [ABSTRACT FROM AUTHOR]

Among the multitude of ceramic fragments, there occasionally appear handles of unusual shapes, or the remains of large dome-shaped lids. Such vessels were used for food preparation in kitchens with open hearths. Ever since prehistory, they have represented a kitchen appliance in daily use to the present day, and they appear in Roman kitchens as well. Various sources refer to this method of food preparation as sub testu. These vessels' segments have also been archaeologically confirmed on Roman sites in Pannonia Inferior and Moesia Superior. There is a type of dish called patina in Roman cuisine, similar to modern-day souffle, which was presumably prepared on plates with a flat bottom and curved, convex, or concave walls. [ABSTRACT FROM AUTHOR]

Abstract Bronze has been positioned as the medium par excellence for sculptural production bearing the aesthetic, symbolic and poetic values that have propitiated the construction of a metallurgical archetype, which has its genesis in its physicochemical, metallurgical and mechanical properties. Of these properties, the formation of the patina is the one that contributes most to the construction of its poetic image, since it is the one that, along with the form, suddenly appears before the spectators, directly affecting their perception of the work. To exemplify this, we analyze the patina of the sculpture La Piedad by Bernardo Vieco using SEM–EDX and XRD. The results show a non-protective patina that, added to the other factors of deterioration of the work, contribute to the drama of the scene that is represented, taking it from pain and impotence before the death of a loved one, to a state of hopelessness and apathy embodied in a bronze that deteriorates over time with environmental factors and neglect in the protection and conservation of the work. Graphical abstract Sculpture La Piedad of Bernardo Vieco and some of their samples evaluated.