Ancient Bronze Research Articles

The study of ancient bronze statue by physical methods

Antique bronze statue is an engineering and cultural construction that corresponds to the level of craftsmanship in modeling, molding, casting, joining methods, surface finishing, and influencing the audience. Some study can be done by physical methods but with historical conclusions. These conclusions may or may not be reliable for a variety of reasons.

Scanning electron microscopy and energy dispersive spectrometry analyses of ancient bronze artefacts of the Urartian period from Yegheghnadzor region, Armenia.

The results of the analysis on some fragments of bronze belts and a bowl discovered from southwestern Armenia, Yegheghnadzor archaeological site, are discussed. The samples are dated to the 7 and 6 BCE from the Urartian period. The artefacts were corroded, and a multilayer structure was formed. To study the stratigraphy of layers and their composition, the samples were analysed using scanning electron microscopy and energy dispersive spectrometry (scanning electron microscopy (SEM)-EDS) and optical microscopy techniques. The bronze finds appear with the typical incrustations, rich in alloy alteration compounds. Concentrations of copper and tin in the alloys were quantified by SEM-EDS: The pattern and the percentage of the alloy are the same for the belts. Regarding the bowl sample, it is constituted by two foils, perfectly in contact but different in colour, thickness and composition. The results evidenced that only two elements participate in forming alloy composition in the samples: Cu and Sn. The tin content is variable from 7.75% to 13.56%. Other elements such as Ag, As, Fe, Ni, P, Pb, Sb and Zn are lower and more than 1% and can be considered as impurities.

Study on the Middle Bronze Age Disc-Butted Axe Ornament from Archaeometallurgical Point of View

Our research was conducted on a copper disc-butted axe, with a surface decoration made of a tin-based alloy, which was found east of the Carpathian Mountains in the Moldavian Plateau. This unique piece is thought to belong to the Middle Bronze Age in the Western Carpathians—Wietenberg, Suciu de Sus and Otomani–Füzesabony cultures. In order to evaluate the application process and the origin of the ores used, the surface and volume phase variation of the concentration of the metal components of the basic alloy (copper) and of the ornament was analysed using optical microscopy (OM), stereomicroscopy (SM) and SEM-EDX. The archaeometric features, formed both during its use and during its lying in the archaeological site, were identified and later used in archaeometallurgical evaluations and in determining the preservation condition of the two components (axe and ornament) on the surface, interface and in stratigraphic section. Experimental data revealed that, after its casting in porous silicon stone moulds, the object was coated with a thin film by immersion in an easily fusible tin alloy, which included copper as the major alloying component and arsenic and iron as minor components. After finishing the shiny white coat, a beautiful decoration was applied by incision and engraving. Used as a battle axe, it also had a rank function, as it belonged to the community leaders. The data prove the ability of ancient craftsmen to design and process copper alloys to obtain authentic extremely beautiful artefacts, which provide new possibilities to reveal the social and symbolic function of certain ancient bronze objects.

Micro-Stratigraphical Investigation on Corrosion Layers in Ancient Bronze Artefacts of Urartian Period by Scanning Electron Microscopy, Energy-Dispersive Spectrometry, and Optical Microscopy

The results of the analysis on some fragments of bronze belts and a bowl discovered from southwestern Armenia at the Yegheghnadzor archaeological site are discussed. The samples are dated to the 7–6th millennium BCE from the Urartian period. The artefacts were corroded, and a multilayer structure was formed. To study the stratigraphy of layers and their composition, the samples have been analyzed using SEM-EDS (Scanning Electron Microscopy, Energy-Dispersive Spectrometry) and OM (Optical Microscopy) techniques. The bronze finds appear with the typical incrustations rich in alloy alteration compounds. Concentrations of copper and tin in the alloys were quantified by SEM-EDS: the pattern and the percentage of the alloy are the same for the belts. Regarding the bowl sample, it is constituted by two foils perfectly in contact but different in color, thickness, and composition. The results evidenced that only two elements participate in forming the alloy composition in the samples: Cu and Sn. The tin content is variable from 7.75% to 13.56%. Other elements such as Ag, As, Fe, Ni, P, Pb, Sb, and Zn make up less than 1% and can be considered as impurities.

Color in Ancient Chinese Bronzes

Color in Ancient Chinese Bronzes

Guidelines for Topology Optimization as Concept Design Tool and Their Application for the Mechanical Design of the Inner Frame to Support an Ancient Bronze Statue

For the past few decades, topology optimization (TO) has been used as a structural design optimization tool. With the passage of time, this kind of usage of TO has been extended to many application fields and branches, thanks to a better understanding of how manufacturing constraints can achieve a practical design solution. In addition, the advent of additive manufacturing and its subsequent advancements have further increased the applications of TO, raising the chance of competitive manufacturing. Design for additive manufacturing has also promoted the adoption of TO as a concept design tool of structural components. Nevertheless, the most frequent applications are related to lightweight design with or without design for assembly. A general approach to integrate TO in concept designs is still missing. This paper aims to close this gap by proposing guidelines to translate design requirements into TO inputs and to include topology and structural concerns at the early stage of design activity. Guidelines have been applied for the concept design of an inner supporting frame of an ancient bronze statue, with several constraints related to different general design requirements, i.e., lightweight design, minimum displacement, and protection of the statue’s structural weak zones to preserve its structural integrity. Starting from the critical analysis of the list of requirements, a set of concepts is defined through the application of TO with different set-ups (loads, boundary conditions, design and non-design space) and ranked by the main requirements. Finally, a validation of the proposed approach is discussed comparing the achieved results with the ones carried out through a standard iterative concept design.

Archaeometallurgy of Copper and Silver Alloys in the Old World

Abstract The production and processing of advanced materials, namely metals and alloys, began in the Old World about 8000 years ago and developed over many millennia, providing a lasting legacy for modern civilizations. This article gives a brief overview of the production and processing of ancient bronzes and silver in the Old World, and also mentions post-processing problems including corrosion and embrittlement, owing to long-term burial before archaeological recovery.

유리건판으로 보는 북한 지역의 조선 후기 범종과 향로

Gelatin dry plates produced in Korea during the colonial era by the Japanese Government-General show some late-Joseon Buddhist craftworks at temples currently in North Korea, such as Buddhist temple bells and incense burners. These include five bells from the seventeenth century, one from the eighteenth century, another from the nineteenth century, and the Jade Gui-shaped Incense Burner and Gilt-bronze Ding-shaped Incense Burner at Yujeomsa Temple.<BR> Among the late-Joseon Buddhist temple bells depicted in gelatin dry plates are the Bell with Inscription of the Sixth Year (1633) of the Reign of Emperor Chongzhen and Bell with Inscription of the Fifth Year of the Reign of Emperor Shunzhi at Seokwangsa Temple; Bell with Inscription of the Tenth Year of the Reign of Emperor Kangxi and another bell from the late seventeenth century at Gwijusa Temple; the Bell with Inscription of the Thirtieth Year(1691) of the Reign of Emperor Kangxi at Seongbulsa Temple; Bell with Inscription of the Forty-seventh Year (1708) of the Reign of Emperor Kangxi at Jangansa Temple; and Bell with Inscription of the Tenth Year (1830 or Gyeongin Year) of the Reign of Emperor Daoguang. The artisans who produced them can be identified based on the inscriptions and styles of these bells. For example, Cheonbo (天宝) participated in the production of the Bell with Inscription of the Sixth Year of the Reign of Emperor Chongzhen at Seokwangsa Temple; Jijun (智俊) and Taehaeng (太行) worked on the Bell with Inscription of the Thirtieth Year of the Reign of Emperor Kangxi at Seongbulsa Temple; Sain (思印) was involved in the creation of the bell from the late seventeenth century at Gwijusa Temple; Yi Hae-jun (李海俊) and Keukryeon (剋連) created the Bell with Inscription of the Forty-seventh Year of the Reign of Emperor Kangxi at Jangansa Temple; and Yi Man-uk (李萬郁) and Jang Min-cheol (張敏喆) were connected to the Bell with Inscription of the Tenth Year of the Reign of Emperor Daoguang.<BR> As for other bells whose inscriptions do not include the names of the artisans involved, stylistic characteristics can be applied to suggest artisans who might have participated in their production. The creation of the Bell with Inscription of the Fifth Year of the Reign of Emperor Shunzhi at Seokwangsa Temple is likely connected to Jeongu (淨祐), Sinwon (信元), Woneung (元應), and Jijun, all of whom were active in the early and mid-seventeenth century. In the case of the Bell with Inscription of the Tenth Year of the Reign of Emperor Kangxi at Gwijusa Temple, Daehwasa Chwicheong (大化士 醉淸) is presumed to have participated in its production. According to the “List of Properties in Gwijusa Temple Based on the Revised Temple Law,” Chwicheong is recorded as the maker of its bell. However, whether or not he was a monk artisan is unclear.<BR> The gelatin dry plates of these Buddhist temple bells are significant in that they reveal that many seventeenth-century bell-casting artisans, including Cheonbo, Jijun, Taehaeng, and Sain, were active in a broader area than had been previously known as they participated in the creation of bells for temples in both present-day South and North Korea. It is also meaningful that works by these artisans have been identified beyond those known from written historical records.<BR> The gelatin dry plates from North Korean regions show only two incense burners: the Jade Gui-shaped Incense Burner and the Gilt-bronze Ding-shaped Incense Burner. Both were used at Yujeomsa Temple. The late-Joseon royal court imported these Ming and Qing copies of Chinese ancient bronze or jade vessels and bestowed them on the royal temple Yujeomsa. The Ding-shaped Incense Burner that King Jeongjo bestowed upon Yongjusa Temple is a classic example of the offerings given by the royal court to its temples during the late Joseon period. These two incense burners at Yujeomsa Temple are also noteworthy in that they demonstrate the use of copies of ancient Chinese bronze or jade vessel imported by the Joseon royal court before the reign of King Jeongjo.

Pitfalls and Possibilities of Patinated Bronze: The Analysis of Pre-Roman Italian Armour Using pXRF

Despite the importance of weapons and armour as part of material culture in the Mediterranean during the first millennium BCE, such objects have generally not been studied beyond stylistic analyses. Bronze was extensively used in the construction of these materials; however, its characterisation is complicated due to patination and the different manufacturing techniques used. We used portable XRF (pXRF) to non-destructively characterise bronze material in a way that mitigates the distorting effects of patina. Analysis was conducted on 23 pieces of pre-Roman Italian bronze armour. Assays were taken using two different techniques; ‘single point’ assays and ‘cluster’ assays. There is variability visible across assays both on and between items, grouped both geographically and chronologically. We highlight significant trends visible in the results over time and different object types and discuss the utility of pXRF on ancient bronze with recommendations for best practice.

A new application of Fiber optics reflection spectroscopy (FORS): Identification of “bronze disease” induced corrosion products on ancient bronzes

Fiber Optics Reflectance Spectroscopy (FORS) has been widely used in the field of cultural heritage for material identification. Nevertheless, it had been rarely applied in the study of bronze corrosion products. This paper aims at exploring the potential of FORS on corrosion products analysis, proposing it as an innovative non-destructive technique for the condition assessment of bronze artefacts in museum collections. A gilded bronze statue “Vajrasattva Bodhisattva” dated to the Ming dynasty (A. D. 1368-1644) from National Museum of China was investigated. The in-situ FORS analysis was conducted on 36 points, revealing copper trihydroxychloride (atacamite/clinoatacamite) and chalconatronite as two major types of corrosion products. This result was double-confirmed by Raman and XRD analyses of 10 samples taken from these points. It proves that FORS is a very promising technique for non-destructive in-situ detection of chloride-bearing bronze corrosions. It may revolutionize the way of screening artefacts with bronze disease, helping conservators get the distribution “map” of different bronze corrosion quickly and comprehensively, and making appropriate treatment proposals accordingly.

An Investigation of the Production Technique of the Copper Drum as a Percussion Instrument

A copper drum evolved as a percussion instrument from an ancient bronze drum. It inherits the fine casting technology of a copper drum and gives the law of copper drum to form. In the 1980s, influenced by the successful reproduction of Chinesisches Glockenspiel, Huang Zhongyu and Zhang Yingzhong improved the sound of copper drums by combining with the customized beating of bronze drums in the Zhuang region of Guangxi and developed the first generation of fixed tone bronze drums capable of producing modern scales. Out of their love for the bronze drum culture, Tan Anyi and Ya Yunyong, from Donglan Middle School in Guangxi,devoted themselves to seek the sound of bronze drums that modern people could understand. After several experiments, they independently developed a musical bronze drum capable of producing an octave in 2009. The twelve-uniformized tone of the bronze drum could be better integrated with modern stage performance. This would make it possible to present the drum as a percussion instrument as well as reveal its production techniques to audiences, which is the best way to investigate and record its production techniques and analyze its tuning principle.

Предмет восточной торевтики из Новосибирска

Purpose. The article dwells upon the description and interpretation of a unique anthropomorphic Eastern toreutics item that was discovered by accident on the territory of Novosibirsk. This item comes from the traditional Ob river crossing site where a cult place with References to the Early Iron Age has already been identified. The study is aimed at attributing the imported item in terms of historical and cultural as well as material science aspects and establishing its relative chronology and possible intended purpose. Results. The functional purpose of the artifact is considered in terms of both its initial origin and possible use in the local environment. The structure and origin of the clothes depicted on the toreutics item are analyzed as being one of the most insightful elements of the cultural background of the product. Based on these data, an assumption concerning an image of silk clothes on the figure was made. Special attention was given to characteristics of a dynamic nature evoked by a volumetric depiction of the tiny sculpture that is likely to correspond to a ritual dance. The established direct and indirect analogies for the toreutics item from Novosibirsk allow state its Eastern origin related to the consequences of the impact of the ancient culture on the vast Eurasian territories. The anthropomorphic product has obvious features of a Buddhistic background represented by an image of the point on the figure's forehead. The energy-dispersive analysis of the metal product allowed determine an alloy composition. It comprised of 62.1 % copper, 15.3 % tin, 15.2 % lead, and 7.4 % zinc. Conclusion. The share of tin in the alloy allows it to be identified as a ‘classic’ bronze piece. An extensive share of copper in the metal product brings it closer to the formula of ancient bronze. The item dates back to the turn of the epoch and is likely to be related to the Indian and Greek cultural tradition.

Retrospect and Reflection on the Study of Early Bronze Drums in China and Vietnam

Bronze drum research is the focus of ancient bronze culture research in southern China and Southeast Asia. Due to different archaeological excavations and academic research traditions, Chinese and Vietnamese scholars have formed completely different views on the development and evolution of early bronze drums. In recent years, reflections on the methods haven been conducted. Some scholars have tried to put the development and evolution of bronze drums in the overall framework of the bronze cultures in China and Southeast Asia, and have obtained some new understandings. Of course, in addition to the change of research paradigm, we also need to strengthen the scientific detection of early bronze drums and the employment of various theories, in order to further expand the breadth and depth of the bronze drum research, and promote it into a new stage.

A Group of Late Antique Bronze Coins Found at Carthage (Sidi Daoud) in the Early 1800s

An ensemble of 29 Roman, Vandalic, and Byzantine coins described by J. E. Humbert in a manuscript written between 1815 and 1819 and preserved in C. J. C. Reuvens’ Archives in Leiden’s Rijksmuseum van Oudheden is discussed. According to Humbert, the coins were contained in a fragmented Hellenistic unguentarium that was said to have been found beneath an inscribed Christian tombstone at Sidi Daoud, in the environs of ancient Carthage. The most recent coin is a rare nummus of Maurice Tiberius that probably was minted at Carthage. It is unlikely that this group of coins is a funerary deposit, because the tombstone is at least a century earlier than the coins ; it is also uncertain whether they represent a hoard, although similar assemblages of coins have been found in controlled excavations.

A preliminary approach on point cloud reconstruction of bronze statues through oriented photogrammetry: the “Principe Ellenistico” case

Close-Range Photogrammetry is a widespread and efficient technique in the 3D acquisition of artefacts, particularly in fields like Cultural Heritage. Despite this wide usage, also due to a convenient quality/cost ratio, it shows some limitations due to light conditions as well as the artefact surface finishing. In this paper, we would like to report the assessment of a photogrammetry approach to 3D capture metal reflective surfaces, such as bronze, which is a widely used material in ancient statues. To this aim, we propose a photogrammetry workflow based on systematic steps capable of overcome some of the main issues of reflective surfaces. To validate this approach, the developed 3D model is compared to a more accurate model of the same artefact, obtained with a 3D scanner. As a case study, we selected the Principe Ellenistico, an ancient bronze statue conserved in the Museo Nazionale Romano (Rome, Italy), of which a photogrammetric model is firstly developed and then compared to the scanned one.

The Copper-Arsenic Eutectic and the Cu&lt;sub&gt;3&lt;/sub&gt;As Phase

In ancient bronze ingots Cu3As was observed beside other impurities like Sb. Moreover, the Cu-As bronzes were studied concerning the decrease in As during melting respectively remelting. To verify the microstructure and hardness of the eutectic and Cu3As phase appropriate mixtures were produced by melting pure Cu and As. The eutectic point in the Cu-As system is at 685 °C and 20.8 wt. % As and the Cu3As phase with 29.56 wt. % As melts at 827 °C. In the sample´s core the microstructure is a homogeneous eutectic, but near the surface it becomes hypoeutectic, i.e. an As loss took place. The lamella thickness of the eutectic was in the range of about 1 µm. The sample with a Cu3As composition showed a proeutectic microstructure with mainly Cu3As and a small amount of eutectic. In the large Cu3As crystals twin lamellae were observed. Additionally, by Vickers indents new twins were introduced. The microhardness of the Cu-As solid solution is 78 HV0.025, of the eutectic 125 HV0.025 and of the Cu3As phase 158 HV0.025. On some surfaces of the Cu3As sample a Cu-rich phase was observed. We are not able to explain this phenomenon, but it is definitively no “inverse segregation”.

The Group Photograph as an Imbricated Ritualistic Event: Duanfang and His Altar Bronzes in Late Qing Antiquarian Praxis

Conceptualising an alternative to the Rieglian analyses of the correlation between power and composition in group portraiture, this article proposes a ritualistic approach to understanding the group photograph and its commemorative purpose. The proposal is raised through a case study of the photograph of Tohoro Duanfang (1861–1911) and an assembly of scholarly officials with the altar bronzes in his collection. Despite the uncertainty about its date and location, the photograph has been widely published in books on Chinese ancient bronzes and the culture of collecting. This article dates, decodes and contextualises this image within the imperial tradition of reinstating ancient bronzes in Confucius worship. It also discusses photography’s primacy in the late Qing antiquarian praxis of studying, cataloguing and displaying bronzes. This study demonstrates that the process of taking a group photograph consists of a composite ritualistic event in which a ‘pro-photographic’ event is imbricated with a ‘photographic event’. This imbricated flow of event and ritual may shed light on understandings of group photographs with an intelligibility that is not only visual, but also temporal.

Micro-slag and “invisible” copper processing activities at a Middle-Shang period (14th-13th century BC) bronze casting workshop

Micro-slag artefacts from ancient bronze casting workshops were largely ignored in previous research despite their rich information potential. Current research demonstrates they could significantly enhance our understanding about past metallurgical activities but their identification requires careful in-situ analysis and a well-designed sampling strategy. Here we present an innovative methodology combining in-situ geochemical survey, wet-sieving of soil samples and detailed microscopic study, employed to investigate an important Middle-Shang site, Taijiasi, in the Huaihe River valley. The micro-slags from this site revealed that in addition to bronze alloying and casting, raw copper refining was also practiced. Material evidence for the refining process was not immediately visible in the archaeological excavation since most slag was mechanically crushed to retrieve any copper trapped in them, leaving only micro-slag fragments typically smaller than 3000 μm (3 mm). The fact that most micro-slag was recovered from one sector (H234) of a small building (F16) located on the same platform as the elites’ long houses suggests that mechanical processing of refining slag was conducted in a confined area and closely supervised. It might reflect people of this site valuing copper as a highly precious material and making all effort to recover copper otherwise lost in slag. This find will potentially shed new light on a range of important issues of Shang archaeology, including the regional variation of Shang metallurgical styles and the provenance of copper in the Shang period. This research also encourages researchers to look into archaeological soil samples with abnormally high copper content and understand the particles in them causing these high readings.

Spontaneous Symmetry-Breaking in the Corrosion Transformation of Ancient Bronzes

In general, during long-term museum conservation, ancient bronzes will generate new corrosion products also called the “secondary corrosion” on the surface of the unearthed “primary corrosion” products due to various environmental conditions. In this paper, the corrosion stages of several ancient Chinese bronzes are characterized by using optical microscope (OM), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and Raman spectrometer (Raman). It is found that there exist phase transformation relationships in between the “primary corrosion” and the “secondary corrosion” stages (i.e., (1) the crystal lattice type tends to transform from a high symmetry system to a low symmetry system; (2) in case of the same crystal lattice type, the corrosions exhibit an inter-transformation or symbiosis). It is interesting to note that these transformation rules are very consistent with the well-known physical law of “spontaneous symmetry-breaking”, which won the 2008 Nobel Prize in Physics and also has been considered to be general law of nature, in addition to the principle of Gibbs free energy reduction. The significance of this discovery allows us to achieve the predictability and controllability of the bronze corrosion products (i.e., to predict the corrosive trends in advance and control the “second corrosion” by adjusting the conservation conditions. This research provides a novel conservation concept of ancient bronzes.

“Inward Growth” Corrosion and Its Growth Mechanism in Ancient Chinese Bronzes

ABSTRACTWe divide the corrosion products on ancient bronzes into two categories, i.e., "inward growth" and “outward growth” corrosions. Several selected Chinese ancient bronzes with the "inward growth” corrosion are studied; and their chemical compositions, microstructures and morphologies are characterized systematically. According to the results, it is found that the “inward growth” corrosion can be further divided into three types, i.e., "noble patina", "noble-like patina" and "lamellar peeling patina". We propose that the growth mechanism of the “inward growth” corrosion is that the corrosion initiates at and develops along α-Cu phase. Furthermore, the effect of alloy Sn content on the “inward growth” corrosion is also studied.