32 research outputs found
The influence of Qing glass technology on Qianlong and Jiaqing painted enamel copperwares
The white enamel surfaces of ten Chinese painted enamels dating to the Qianlong and Jiaqing periods (1736â1820) were studied with Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICPMS). These enamels are opacified with lead arsenate, a dramatic change in technology from fluorite and lead stannite opacification used in Chinese and European enamels before the 18th century. The primary goal of this project was to test the hypothesis that boron is a significant component in Chinese painted enamels. Borax (Naâ[BâOâ
(OH)â]·8HâO) was used by glassmakers working in the imperial workshops in Beijing in the mid-18th century, and boron has been detected in some examples of Qing glass and enamels. Quantitative analyses of major, minor, and trace level elements were carried out with LA-ICPMS. Three compositional groups were identified by the amount of borax in the enamel: high borax (at 6.7% B2O3), low borax (up to 1.3% B2O3), and borax free. The results show that it is possible to distinguish between objects made in Beijing and Guangzhou through elemental analysis, and that there are two distinct compositional groups of Chinese painted enamel produced in Guangzhou during this period
Amphores vinaires Gauloise 4 de Narbonnaise (France) exportées à CarthagÚne (Espagne) ? Analyse statistique exploratoire multidimensionnelle de données géochimiques
La vaste distribution des amphores de type Gauloise 4 dans le monde mĂ©diterranĂ©en durant le Haut-Empire tĂ©moigne de lâintense activitĂ© du commerce vinaire de la Narbonnaise durant cette pĂ©riode. La diffusion de ce type dâamphore dans la PĂ©ninsule ibĂ©rique, attestĂ©e par quelques amphores, demeure encore mal connue. La rĂ©cente dĂ©couverte Ă CarthagĂšne de plusieurs fragments de Gauloise 4 prĂ©sentant de fortes ressemblances avec les productions de Narbonnaise nous a conduits Ă rĂ©aliser une sĂ©rie dâanalyses chimiques afin de nous assurer de leur provenance. Ainsi, huit amphores ont Ă©tĂ© analysĂ©es par fluorescence de rayons-X et comparĂ©es Ă la base de donnĂ©es de la Maison de lâOrient de la MĂ©diterranĂ©e, riche de plus de 700 rĂ©sultats dâanalyses dâamphores produites dans le sud de la France. Les donnĂ©es ont ensuite Ă©tĂ© traitĂ©es en utilisant une mĂ©thode statistique de partitionnement mixte combinant lâAnalyse en composante principale et lâalgorithme des NuĂ©es dynamiques (dĂ©rivĂ© de la mĂ©thode K-means). Les rĂ©sultats ont ensuite Ă©tĂ© validĂ©s par une analyse factorielle discriminante associĂ©e Ă une validation croisĂ©e. Les probabilitĂ©s dâattributions obtenues nous ont permis de conclure quâau moins cinq des huit Ă©chantillons ont Ă©tĂ© fabriquĂ©s dans les ateliers de Narbonnaise.Strength of wine trade during early Roman Empire is evidenced by the wide geographical distribution of Gauloise 4 amphorae crafted in Narbonnensis area. Extension of that trade to Iberian Peninsula has previously been recorded, but remains very poorly understood. Recent discovery in Cartagena of several pottery sherds closely similar to Gaulish productions led us to investigate their provenance. Eight different amphorae sherds were analyzed using X-ray fluorescence and compared to a solid database of more than 700 amphorae samples produced in south of France. Data was then analyzed by a hybrid clustering method combining Principal component analysis and Dynamic cloud algorithms derived from K-means method. Results were subsequently validated with a Factorial discriminant analysis associated to a cross-validation method. The very high probability of attribution we obtained allowed us to conclude that at least five of the eight samples were produced in workshops located in the Narbonnensis area
The dating and provenance of glass fragments from the site of Serabit el-KhĂądim, Sinai
Serabit el-KhĂądim, located on the western coast of the Sinai Peninsula, is the site of an ancient turquoise mine established in the early 12th Dynasty (c. 1985 BCE) and active between the 18th and 20th Dynasties (c. 1550â1136 BCE). The temple dedicated to Hathor at Serabit detail the number of offerings made, thereby recording the level of activity at Serabit during each reign. The last offerings were made by Rameses VI (1143â1136 BCE) corresponding with the collapse of the Late Bronze Age before the site was abandoned. 976 glass fragments were given to the Ashmolean Museum by Flinders Petrie following his 1905â6 excavations. 41 fragments from the collection were selected for LA-ICP-MS analysis with the aim of provenancing and dating an unknown collection of glass using composition and available stylistic features to further narrow the date of manufacture and therefore indicate the possible workshop of origin. The analysis showed that all 41 fragments are of Egyptian provenance and of standard Late Bronze Age high magnesia plant ash glass, except one fragment which is a unique example of natron blue glass applied as decoration to a white plant ash vessel body. Subtle compositional differences show that 18th Dynasty plant ash glass, plant ash Ramesside glass and natron Ramesside glass are all present, therefore corresponding with the known Egyptian activity at Serabit
Characterising Chinese Ru ware in the Sir Percival David collection at the British Museum using handheld XRF analysis
Ru ware is a very rare and highly prized stoneware from the end of the Northern Song period of China (960â1127 CE). Stylistic and art historical work by Regina Krahl (2021) suggests that a brush washer in the Sir Percival David Collection, housed in the British Museum, might be Ru rather than Korean Goryeo ware as previously thought. This paper reports the analysis of the glaze of this piece by handheld XRF in comparison with 10 pieces of Ru and 10 pieces of Goryeo ware. Despite the compositional similarity of the glazes, the analysis was able to show conclusively that the piece is Ru ware. The work has implications for the analysis of Chinese stoneware and beyond, showing that it may be possible (under the right conditions) to distinguish different productions relatively quickly and easily
Analyses of the brown stain on the Parthenon Centaur head in Denmark
In 1688 two sculptural fragments, a head of bearded man and a head of an unbearded youth, arrived in Copenhagen, sent from Athens as a gift to King Christian 5. They were placed in the Royal Kunstkammer, their provenance given as the Temple of Artemis in Ephesos, one of the Seven Wonders of the World. Almost a hundred and fifty years later, in the early 1820âs they were noticed and studied by two scholars independently visiting the Kunstkammer. However, both concluded that the two heads belonged to one of the metopes decorating the south side of the Parthenon temple on the Acropolis in Athens, showing fighting between Greeks and the mythical Centaurs, part man and part horse. In the 1830âs another sculptural fragment, a horseâs hoof, obtained through the German archaeologist and state antiquary of Greece, Ludwig Ross, reached Copenhagen. It was forwarded by the Danish consul to Athens, C.T. Falbe, as a gift to King Christian 8. The inventory reads: â⊠was found on the Acropolis near the Parthenon temple and is supposed to belong to one the Centaurs on the metopes.â The present paper focuses solely on the head of the Centaur.
A brown stain was noticed on the Parthenon marbles as early as 1830 by the British Museum and has ever since eluded a deeper understanding of its genesis despite many investigations and attempts of analyses. A quite similar brown stain can be observed on the Centaurâs head in Copenhagen as well.
The present study reports analyses by LA-ICP-MS, SEMâEDX, ”XRD, GCâMS, and LCâMS-MS, as well as optical microscopy of five small samples sequestered in 1999 from the Centaur head curated by the National Museum of Denmark. Our analyses show that the brown stain consists of two consecutively added surficial layers of the calcium oxalate minerals whewellite and weddellite. Despite a thorough search using proteomics, we have found no viable organic precursor material for the oxalates. Our results do not solve the mystery of the formation of the brown stain, but they do further qualify the structure and characterization of the brown stain
Indurated soil nodules: a vestige of ancient agricultural practices?
The identification of controlled fires in ancient agricultural systems is important for understanding how past societies managed the landscape. Although the use of fire in agriculture is documented in recent historical records, and combustion markers can persist in soils over a long time scale, this is a complex issue because combustion traits in general are ubiquitous. Archaeopedological surveys undertaken in an ancient forest in Burgundy (France) have led to the recovery of several red indurated nodules scattered in the soils. Gallo-Roman housing structures and parcels were recognized using light detection and ranging mapping, stimulating questions about the understanding of the nature of these nodules. Elemental and structural analyses by X-ray fluorescence and X-ray diffraction (XRD) confirmed the local origin of these features by comparing their composition with on-site sediments, and thermoluminescence dating placed the samples in the Medieval period. The results cast light on the nature of the nodules and how they can be related to controlled fires used in agricultural practices. Even though questions remain about which processes lead to the formation of the nodules, the firing temperature estimated via XRD analysis seems to be in agreement with that used in the âparing-and-burningâ technique. The present study provides new information about medieval agriculture practices from the 10th to the 12th centuries CE and shows how past societies managed the opening and maintenance of agricultural fields using natural resources and âarchaeologicalâ remains from the antique period
Materials and technology of mosaics from the House of Charidemos at Halikarnassos (Bodrum, Turkey)
An excavation in 1856 by Charles T. Newton and a re-excavation in 1990â93 by a joint Danish-Turkish team revealed several mosaic floors in a late-antique domus from the fifth century CE, now called the House of Charidemos. Nineteen tesserae from the floor have been analysed by laser ablation inductively coupled plasma mass spectrometry, Raman micro-spectroscopy, scanning electron microscopy with energy dispersive X-ray analysis, and X-ray diffraction. Seven tesserae were made of opaque glass, eleven from various rock/lithic materials, while one of them was a ceramic fragment. This case-study reports the first analyses undertaken of tesserae from late-antique Halikarnassos. The results show the use of recycled SbâMn decoloured glass and two types of red glass. A comparison with tesserae from other sites in Anatolia from the same period shows similarities in the base glass composition, but also some particularities of the colouring and opacifying agents used for the mosaic of the House of Charidemos. The characterisation of the stone tesserae shows a homogeneity in the choice of the materials of the same colours, but no certain provenance has been established in the present work mainly due to the lack of comparative materials
Correction to: Investigations of the relics and altar materials relating to the apostles St James and St Philip at the Basilica dei Santi XII Apostoli in Rome
Following publication of the original article [1], the authors identified an error in an authorâs name. The incorrect name was: Erika Ribercini. The correct author name is: Erika Ribechini. The author group has been updated above and the original article [1] has been corrected
Thermoluminescence and radiocarbon dating of pre-colonial ceramics and organic midden material from the US Virgin Islands: outline for a revised chronology
A sample of 128 pottery shards curated by the National Museum of Denmark, from seven archaeological sites in the US Virgin Islands, has been dated using the thermoluminescence dating (TL) technique with the purpose of refining local pre-colonial pottery chronology. The results of the TL-dating generally confirm chronologies offered by Wild for St. John and there is considerable variation identified in traditional frameworks due to overlap in distributions of various pottery styles. The results of this study show that the Virgin Islands offer a viable space for the application of TL-dating, and that TL-dating offer a reliable addition to the traditional radiometric radiocarbon technique in pre-colonial midden contexts. Using the TL-technique for dating of pottery assemblages allows for a nuanced chronology and better understanding of settlement timing, socio-cultural interaction, and information transmission
Release of lead from Renaissance lead-glazed ceramics from southern Denmark and northern Germany: Implications from acetic acid etching
Lead-glazed potsherds from archaeological excavations at six Renaissance (1536â1660 CE) sites in southern Denmark and northern Germany have been subjected to etching experiments using 4 wt% acetic acid. The extracts of 45 sherds were analysed by Inductively Coupled Plasma Mass Spectrometry. At one site, the ducal hunting castle of GrĂžngaard, Pb levels in acid extracts from glazed dishes were so high (up to 29,000 ”g Pb cmâ2 dayâ1) that acute toxic effects likely occurred if the dishes were used for serving food containing vinegar. More moderate acid-etching Pb levels were found in dishes from other sites, but they still exceed the WHO critical level if used daily. Acetic acid etching experiments performed on pipkins (three-legged cooking pots with a handle) yielded somewhat lower Pb extract values, averaging ca. 25 ”g Pb cmâ2 dayâ1. Taking into account the widespread use of pipkins for cooking, they might easily have led to a higher weekly Pb intake than the use of the moderate-level dishes. The question remains whether such high levels of Pb exposure during meals led to injurious Pb intake. Prior skeletal analyses have shown that medieval to early modern individuals from the area, especially in towns, were exposed to Pb. While exposure could have come from various sources other than lead-glazed ceramics, such as cosmetics, paint, antibacterial ointments, and lead water pipes, widely distributed lead-glazed ceramics had the potential of being a main source of Pb. How the pottery was actually used is uncertain, and it certainly was not evenly distributed across all segments of society, but the etching experiment results suggest that severe poisonous effects could have resulted from the use of lead-glazed Renaissance ceramics