Governance under the shadow of the law: trading high value fine art

The market for paintings by well-known artists is booming despite widespread concern about art crime and difficulties in establishing provenance. Public law enforcement is imperfect, and court cases often are deemed problematic. So how is the thriving art market governed in practice? We analyze the protocols used by the top auction houses to identify and resolve problems of illicit supply—fakes, forgeries and items with defective legal titles—through the lens of institutional analysis. We uncover a polycentric private governance system in which different actors govern distinct but overlapping issue areas, motivated by profit, prestige, or the search for truth. When the financial stakes rise, opportunistic behavior undermines the credibility of private governance. We argue that as litigious, super-rich investors entered the art market, the interaction between public law and the traditional private governance system restricted the supply of “blue chip” art, driving the escalation of prices

Glass: Lapis Lazuli from the Kiln

e-NewsletterToday glass is all around us, it is familiar to us all in windows, vessels, spectacles, a myriad of uses. However, when glass was first made in the Late Bronze Age (LBA) around 1500 BCE it was very different

European cobalt sources identified in the production of Chinese Famille Rose porcelain

The blue pigments on 112 fragments or small objects of Qing Dynasty Chinese, 95 of underglaze blue and white and 17 overglaze enamelled porcelains were analysed by LA-ICPMS. The underglaze blues on both blue and white and polychrome objects were created with a cobalt pigment that was rich in manganese with lesser nickel and zinc. This suite of accessory elements is generally considered to be characteristic of local, Chinese, sources of pigments. However, the blue enamels were very different. The cobalt pigment here has low levels of manganese and instead is rich in nickel, zinc, arsenic and bismuth. No Chinese source of cobalt with these characteristics is known, but they closely match the elements found in the contemporary cobalt source at Erzgebirge in Germany. Textual evidence has been interpreted to suggest that some enamel pigment technologies were transferred from Europe to China, but this is the first analytical evidence to be found that an enamel pigment itself was imported. It is possible that this pigment was imported in the form of cobalt coloured glass, or smalt, which might account for its use in enamels, but not in an underglaze, where the colour might be susceptible to running. Furthermore, the European cobalt would have given a purer shade of blue than the manganese-rich Chinese cobalt

High-resolution X-ray diffraction with no sample preparation

It is shown that energy-dispersive X-ray diffraction (EDXRD) implemented in a back-reflection geometry is extremely insensitive to sample morphology and positioning even in a high-resolution configuration. This technique allows high quality X-ray diffraction analysis of samples that have not been prepared and is therefore completely non-destructive. The experimental technique was implemented on beamline B18 at the Diamond Light Source synchrotron in Oxfordshire, UK. The majority of the experiments in this study were performed with pre-characterized geological materials in order to elucidate the characteristics of this novel technique and to develop the analysis methods. Results are presented that demonstrate phase identification, the derivation of precise unit-cell parameters and extraction of microstructural information on unprepared rock samples and other sample types. A particular highlight was the identification of a specific polytype of a muscovite in an unprepared mica schist sample, avoiding the time-consuming and difficult preparation steps normally required to make this type of identification. The technique was also demonstrated in application to a small number of fossil and archaeological samples. Back-reflection EDXRD implemented in a high-resolution configuration shows great potential in the crystallographic analysis of cultural heritage artefacts for the purposes of scientific research such as provenancing, as well as contributing to the formulation of conservation strategies. Possibilities for moving the technique from the synchrotron into museums are discussed. The avoidance of the need to extract samples from high-value and rare objects is a highly significant advantage, applicable also in other potential research areas such as palaeontology, and the study of meteorites and planetary materials brought to Earth by sample-return missions

Ancient Biographies: Trace element analysis to investigate provenance and transportation mechanism of Late Bronze Age glass

Volume 1, Issue 2 (2017), delayed publication 2019LA-ICPMS analysis was carried out on a scaraboid blue glass bead (Hunterian Museum Glasgow, D.1921.39) excavated from Tomb 27 in Gurob, in the Southern Fayum region of Egypt. Gurob is known to have been the site of a ‘harem palace’ established in the reign of Tuthmosis III (1479-1425 BC). The tomb was located at the northernmost point of the New Kingdom cemetery and was undisturbed, containing the remains of seven females and two children, and was dated by the excavators to between the reigns of Amenophis I (1525-1504 BC) and Tuthmosis III. The glass scarab was coloured by copper and trace element values of La, Cr, Ti and Zr exhibited compositional consistency with glasses from Mesopotamia, rather than from Egypt. Therefore, the glass scarab represents a rare example of Mesopotamian glass to be discovered in Egypt, in addition to being some of the earliest glass found. The finds support iconographic references in the Hall of the Annals at Karnak to the import of early glass into Egypt. The implication is that these beads represent luxury items transported into Egypt by high-ranking foreign women perhaps in connection with the Gurob harem palace

Technological connections in the development of 18th and 19th century Chinese painted enamels

Chinese painted enamel is an artistic tradition of enamelled copperwares developed during the Kangxi period (1662–1722), commonly referred to as Canton enamel after the Wade-Giles spelling of Guangzhou. In this study, enamel fragments from areas of damage in the decorated surface of ten Chinese painted enamel objects dating to the 18th and early 19th century in the collections of the Ashmolean and Fitzwilliam Museums were non-destructively analysed with ESEM-EDX (Environmental Scanning Electron Microscopy - Energy Dispersive X-Ray Spectroscopy). After analysis, the enamel fragments were reattached to the objects using a conservation grade adhesive. Quantitative EDX elemental analysis is presented for the white enamel, underdrawings, eight painted enamel colours, outlines, and gilding. The enamel-glass composition, opacifier and colourants are discussed and compared to ceramic, glass, and enamelled metal technologies in use during the Ming Dynasty (1368–1644). The results show that Chinese painted enamels combine Chinese and European technology to create a new and distinct art form

The dating and provenance of glass fragments from the site of Serabit el-Khâdim, Sinai

Serabit el-Khâdim, 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. 1550–1136 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 (1143–1136 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 1905–6 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

Early medieval garnet-inlaid metalwork: a comparative analysis of disc brooches from early Wessex

Garnet-inlaid metalwork was an emblem of elite culture in the early medieval North Sea world. This study compares three Anglo-Saxon garnet-inlaid brooches that are exceptionally similar in design and appearance. All three date to the seventh century, a period that saw the emergence of leading families that used such deluxe dress items to enhance their political position. The central hypothesis explored here is that the brooches were produced by the same, or by closely linked, goldsmiths working under the patronage of such a family. Integrated analysis was conducted using microscopy, CT scans, XRF and XRD, in part to establish whether the garnets used came from the same or different sources

Radiocarbon dating of Early Egyptian pot residues

A number of absolute dating techniques are now used in archaeology, from dendrochronology to a variety of luminescence and radiometric methods.1 However, radiocarbon dating remains the most effective approach for the early historic periods. This is largely because of the levels of precision achievable, but also due to the diversity of materials that can be dated, and the ease with which radiocarbon dates can be connected to specific events in the past. Radiocarbon dating can be employed on all carbon-containing materials that are biogenic in origin. Common sample types include items fashioned from plant material, such as textiles and basketry, and the remains of animal and human tissue. Radiocarbon estimates denote the time elapsed since the antecedent organism ceased exchanging carbon with its environment. For human and animal remains this is invariably taken to be the time of death, and for plants it is most commonly the time at which the material was harvested or felled. With the advent of accelerator mass spectrometry (AMS) in the 1980s, it became possible to conduct radiocarbon analysis on samples several orders of magnitude smaller than preceding techniques.2 Typically, AMS can produce reliable dates on as little as 10 mg of plant material and just 250 mg of whole bone powder. As a result, AMS accounts for a large proportion of the dates made on archaeological samples. No form of radiocarbon dating can, however, provide direct estimates for the age of lithic or ceramic artefacts. The principle difficulty lies in relating any datable material obtained to the manufacture or use of the object in question. In fact, carbonaceous inclusions in such materials are likely to be of geological age, and therefore beyond the 50,000 year detection limit of the technique. Consequently, there remains a disjunction between radiocarbon results and dates based on ceramic seriation. One possibility at bridging this divide comes from the radiocarbon dating of organic residues adhered to specific ceramic types. This prospect was investigated for Early Egypt by an interdisciplinary research team from the University of Oxford, University College London and Cranfield University