'Boundary Objects' in Archaeological Finds and Environmental Research: Using Bowker and Star's Concept of the 'Boundary Object' to Analyse and Interpret Disparate Archaeological Legacy Data

Is a big data analytical approach viable using archaeological artefact and ecofact data? In particular is it possible to use Bowker and Star's (1999) concept of the 'boundary object' to manage the issues caused by data scale, complexity, diversity and variable information standards when attempting to carry out this kind of research? This paper reviews the theoretical and methodological debates around archaeological big data as they impact upon research into assemblages of artefacts and ecofacts and presents a methodology for the construction and use of a large archaeological database of legacy artefact and ecofact data created as part of the English Landscapes and Identities Project at the University of Oxford.

XANES at the Cl K-edge as a relevant technique to reveal the iron archaeological artefact dechlorination treatments

Degradation state evaluation, corrosion diagnosis methods' reliability, and also the development and improvement of conservation strategies are dramatically important to preserve iron archaeological objects.

CAULDRONS IN THE CULTURAL TRADITIONS OF THE OB UGRIANS AND SAMOYEDS: THE ARCHAEOLOGICAL ARTIFACT AND ‘LIVING’ TRADITION

The first part of the article published in this journal considers the archaeological context along with the func-tional, morphological and social aspects associated with cauldrons in the cultural traditions of the Ob Ugrians and Samoyeds of North-Western Siberia. In this work, the authors analyse field ethnographic materials collected from the Khanty (Synya, Voykar, Sob, Kunovat, Polui, Ob, Salym, Yugan, Pim, Tromyogan, Agan, Vakh, Polar Urals), Mansi (Northern Sosva, Lyapin and Lozva Rivers) and Nenets (Yamal Peninsula, Pur and Agan Rivers) in 1980–2018. The study of cauldrons in a ‘living’ culture along with analysing them as an archaeological artefact has greatly expanded the chronological range of the research from the 1st–4th centuries AD to the present time. The archaeological and ethnographic research is based on a structural and semiotic approach. A cauldron, as an ele-ment of material and spiritual culture, associated with the methods for obtaining and preserving energy, is directly related to the experience of using natural resources and to the development of life sustenance models for the Northern communities. Numerous archaeological discoveries of intact cauldrons, as well as their fragments and items made from their fragments in North-Western Siberia, indicate the archaism and the continued use of caul-drons as vessels for storage and cooking; fashionable, prestigious, high-status items; a receptacle for the soul; a divine attribute and a talisman, etc. It is not surprising that the cauldron, whose direct purpose consists in storage and preparation of food, is incredibly versatile in Ob-Ugric and Samoyedic cultures. The cauldron appears in the surviving toponyms and legends of the Nenets, Khanty and Mansi. It acts as a measure of volume and time. Cauldrons possess features and properties of a living organism; they contain the energy of fire and stone-iron. The ability of cauldrons to change their condition and position (full/empty, boiling/not boiling, upside-down/right-side-up) is manifested in their diverse duality making them mediators in the following juxtapositions: peace —enmity, familiar — alien, kinship — property, birth — death, wealth — poverty, happiness— trouble. А cauldron is a symbol of family unity, the source of the power for birth-recovery, as well as an attribute of shamanic rites and a border between the worlds. The high mythical and ritual status of the cauldron is emphasised by its celestial ori-gin.

Concealment and Revelation: The Pola Casket and the Visuality of Early Christian Relics

The archaeological artefact is typically unearthed. It comes to us marked by the depredations of time, tarnished by burial, reclaimed from loss. Yet the perspective of excavation, according to which all objects are disinterred and salvaged for the collection or the museum, with more or less of a contextual history arising from their unearthing, may risk simplifying or ignoring the conditions of their original interment. The differences between the kinds of burial, between the multiple processes at stake in the loss of objects to the earth in the past—insofar as they can be reconstructed—are interesting. For example, the amazingly well-preserved statue of Flavius Palmatus, Consular Governor of Caria and acting Vicar of Asiana at some point before 536 CE, was discovered toppled beside its inscribed base at the west colonnade of the square adjoining the theater of the city of Aphrodisias in Asia Minor, in the mid-twentieth century. It fell in the course of time, we have no idea when—probably as the result of an earthquake—in a city virtually abandoned after the seventh century and was subsequently covered by debris and soil until its excavation in modernity. By contrast, the Meroe head, an over-life-size bronze head of Augustus, which was excavated by the British in Sudan in the teens of the twentieth century, was probably cut from the statue of which it was part and buried by barbarian tribesmen beneath steps leading to the native temple of Victory in the Kushite capital of Meroe in the Sudan. Far from falling where it stood, it was the victim of deliberate iconoclasm and burial by the enemies of the Roman empire, probably shortly after its erection when the Kushites invaded Roman Egypt in 25 BCE. In its buried form it lay as a hidden trophy permanently trampled by the Kushites—a sign of independence from Rome, autonomy, and hatred of the Roman emperor even when the tribesmen had forgotten that it was hidden there. Other kinds of deliberate burial, however, were made by those who owned the objects interred, rather than thieves or rampagers.

REPRESENTATION OF SYNTHETIC SHADOWS ON 3D DIGITAL MODELS FOR THE VOLUMETRIC INTERPRETATION ON CONCAVE-CONVEX ARCHAEOLOGICAL ARTIFACTS

<p><strong>Abstract.</strong> The representation of archaeological artefacts aims for the graphic description of relevant information from the object, to allow for the proper interpretation of evidences from the past. Concavities and convexities are elements often difficult to represent through classical (analogical) representation techniques, especially when these geometrical characteristics are neither continue nor parameterizable. Digital techniques have advanced on the accurate reconstruction of 3D shapes, while attaching real colour to the geometry. However, the perception of concave/convex shapes from photorealistic true-orthoimages continues to be limited, especially when rich and homogeneous textures camouflage slight slope changes or volumetric deformations. In this paper we first critically review the current practice on the representation of solid-of-revolution artefacts with concave-convex predominance, and alternative photorealistic representations aiming at a better understanding of volume and colour. Given the limitation targeted, we then propose a workflow for the creation of true-orthometric maps enhanced by customized shadows. The work-flow integrates considerations on: (i) The orientation of archaeological artefact; (ii) the creation of accurate orthometric images based on Digital photogrammetry techniques; and (iii) the application of synthetic attached and cast shadows according the shape (information) to be represented. The workflow is demonstrated with a sample of plates retrieved from the Rua-das-Madres archaeological site, in Portugal.</p>

Laser cleaning of Cu-based artefacts: laser/corrosion products interaction

<p class="Abstract">This study aims to develop a low invasive and selective laser cleaning procedure for the removal of reactive corrosion products on Cu-based artefacts without damage the substrate. In a preliminary step, laser cleaning was performed on two typologies of artificially corroded copper reference samples. The effect of the variation of laser parameters as pulse duration and output power, was thus evaluated on an oxide layer, simulating a protective patina, and a hydroxychloride layer, simulating a reactive corrosion products layer to be removed. The optimized cleaning procedure was validated on an archaeological artefact, a bronze coin. Morphological, microchemical and microstructural characterizations were performed by means of optical microscopy, confocal microscopy, field emission scanning electron microscopy, X-Ray diffraction and Raman spectroscopy, before and after laser cleaning. The experimental findings show that laser cleaning, in optimized conditions, can reduce the thickness of the hydroxychloride layers slightly affecting the oxide layers. The difference in the interaction with laser radiation of these two layers seems to be mainly related to the difference in grain size and porosity. Notwithstanding these encouraging results, in order to define the real feasibility of the laser cleaning procedure, a further validation on real artefacts is mandatory due to the variation in thickness and composition of the corrosion products formed during long-lasting uncontrolled degradation processes.</p>

ADAPTATION OF INDUSTRIAL HYPERSPECTRAL LINE SCANNER FOR ARCHAEOLOGICAL APPLICATIONS

The spectral characteristic of the visible light reflected from any of archaeological artefact is the result of the interaction of its surface illuminated by incident light. Every particular surface depends on what material it is made of and/or which layers put on it has its spectral signature. Recent archaeometry recognises this information as very valuable data to extend present documentation of artefacts and as a new source for scientific exploration. However, the problem is having an appropriate hyperspectral imaging system available and adopted for applications in archaeology. In this paper, we present the new construction of the hyperspectral imaging system, made of industrial hyperspectral line scanner ImSpector V9 and CCD-sensor PixelView. The hyperspectral line scanner is calibrated geometrically, and hyperspectral data are geocoded and converted to the hyperspectral cube. The system abilities are evaluated for various archaeological artefacts made of different materials. Our experience in applications, visualisations, and interpretations of collected hyperspectral data are explored and presented.