Coloured Prints of the 16th Century: Non‐Destructive Analyses on Coloured Engravings from Albrecht DÜrer and Contemporary Artists

Qualitative investigations of pigments and dyes using micro X‐ray fluorescence spectrometry (micro‐XRF) and visible spectrophotometry (VIS) are suitable non‐destructive methods for the characterization of different colorants in art objects. In this study, several rare coloured engravings from the work of Albrecht Dürer—and, in addition, from the work of Cornelis Cort, Servatius Raeven and Johannes Sadeler—were investigated. The analyses result in specific palettes of colours that were used by different artists or in different workshops for the coloration of engraved images. Starting from these different palettes, it is possible to distinguish coeval colorations that were added in the 16th century from those that were carried out at a later date (e.g., the 19th century).     

DISCOVERY AND CHARACTERIZATION OF AN UNKNOWN BLUE‐GREEN MAYA PIGMENT: VESZELYITE*

Blue‐green mosaic and polychrome masks and funerary offerings from the royal tombs of Calakmul, Mexico, were analysed by scanning electron microscope equipped with energy dispersive X‐ray spectroscopy (SEM‐EDS), X‐ray diffraction (XRD), and particle induced X‐ray emission (PIXE). This led to the first identification of the use of veszelyite, a rare hydrated copper‐zinc phosphate, as green pigment. Analyses of a geological sample of this mineral have been done to confirm the characterization of this Mayan pigment, which might help determine pre‐Columbian trade routes of precious and luxury objects in the ancient Maya Classic period (ad 250–800).     

The chronology of the Neolithic sequence at Dikili Tash,Macedonia, Greece: TL dating of domestic ovens*

The chronological sequence of a major reference site for Neolithic periods in southeastern Europe and the Aegean, Dikili Tash (Macedonia, Greece), has been reassessed by TL. Baked adobe material samples extracted from domestic ovens, directly associated with specific occupational levels, have been studied. The fine‐grain technique has been used for equivalent dose determination. K, U and Th contents and the equilibrium state of U‐series have been measured by low‐background gamma spectroscopy. Since the archaeological levels were already partly excavated, the environmental dose‐rate was evaluated by a reconstruction technique combining laboratory analysis and on‐site measurements. The TL results (weighted average of multiple age determination, oven 400, middle of the Dikili Tash I (DT‐I) phase, 5500 ± 320 bc ; oven 600, end of DT‐I, 4920 ± 310 bc ; house 3, DT‐II, 4260 ± 280 bc ; house 4, DT‐II, 4510 ± 410 bc ) are in general agreement with the timeframe deduced from previous radiocarbon dates. This convergence strengthens the settlement's chronology, established now by independent dating methods.     

Akhalkalaki: The Taphonomy of An Early Pleistocene Locality in the Republic of Georgia

As part of our investigations into the potential of the Republic of Georgia for providing information on early hominin occupation of Eurasia, we report here on Akhalkalaki, a large late Early Pleistocene locality located along the lower slopes of a Miocene andesitic cone. Originally excavated in the 1950s as a palaeontological site, it was re-opened in the 1990s and stone tools were found associated with the fauna, suggesting that it is also an archaeological occurrence. Excavations in the 1950s and 1990s uncovered thousands of bones of an early Galerian fauna, including the remains of new species of Hippopotamus,Equus , and Canis (Vekua, 1962, 1987) and dominated by the remains of Equus süssenbornensis. We present the stratigraphy of the site, which together with faunal correlations and reversed paleomagnetics indicates an age most likely in the late Matuyama Chron, probably between 980,000 and 780,000 years ago. Taphonomic analysis suggests that the fauna was deposited and buried over a short time period, and was heavily modified by carnivores, but we cannot demonstrate involvement by hominins. Based on evidence of abundant krotovina (animal burrows filled with sediment) and the lack of definitive evidence for hominin modification to the bones, the stone tools at the site may have been mixed in with the older fauna. The taphonomic characteristics of the Akhalkalaki bone assemblage are not readily explained with reference to assemblage formation processes developed with actualistic studies that have been mostly conducted in Africa, including carnivore dens, predator arenas, human hunting and scavenging, mass deaths, or attritional bone deposition. Because of extreme anthropogenic modification of the present environments, the temperate setting, and the presence of mainly extinct taxa, local models based on actualistic studies cannot approximate the mammalian ecology reflected in the Akhalkalaki bone assemblage. A few comparisons are made with preliminary taphonomic observations from Dmanisi, an Early Pleistocene Homo ergaster site not far away.     

THE HISTORY OF THE LAWRENCE BERKELEY NATIONAL LABORATORY INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS PROGRAMME FOR ARCHAEOLOGICAL AND GEOLOGICAL MATERIALS

The Lawrence Berkeley National Laboratory pottery provenance group developed standards and instrumental neutron activation analysis (INAA) methods that are used at many archaeometry laboratories around the world. The background and development of ‘Standard Pottery’ and of methods for INAA are described. Early pottery provenance studies are described, and other research programmes, involving obsidian and magmatic mixing, the origin of the stone used for the Colossi of Memnon, and the ‘Plate of Brass’, are mentioned. Research work by the Laboratory included the discovery of the world‐wide iridium anomaly and extensive subsequent research on what has come to be known as the ‘Asteroid Impact Theory’. Characteristics of the analytical programme for pottery provenance work, including overall aims, precision and accuracy, intercalibration, and irradiation and measurement protocols, are discussed. New research areas developed in the past 15 years, to broaden the usefulness of chemical compositional data for archaeological investigation, and examples of recent work, are described. This research, which makes use of high‐precision X‐ray fluorescence analysis in addition to INAA measurements on sample splits, includes distinguishing the products of different workshops located at the same production site, studies on the significance of the distribution of silver in archaeological pottery and the use of high‐precision chemical compositional data as an aid for making chronological distinctions.     

RED PALAEOLITHIC PIGMENTS: NATURAL HEMATITE OR HEATED GOETHITE?*

Yellow goethite (α-FeOOH) and red hematite (α-Fe₂0₃) were used as pigments by Palaeolithic painters. When heated, goethite dehydrates and transforms to hematite Archaeologists wonder whether prehistoric people knew of this property and used it. We present a way to distinguish heated goethite from natural hematite. The methods used are X-ray diffraction and transmission electron microscopy. A double ‘signature’, namely selective broadening of diffraction reflections and porous nanostructure, is evidenced in heated goethite. Coupled with mineralogical associations, this allows us to establish a procedure to investigate the natural or artificial origin of hematite samples. Applied to the Palaeolithic site of Troubat, it reveals no difference between the Magdalenian and Azilian cultures concerning the heat-treatment of pigments; an area specializing in heat-treating pigments, may, nevertheless, have existed inside the cave, which would indicate that heating wax deliberate.     

Advances in Polychrome Ceramics in the Islamic World of the 12th Century AD

As part of a multidisciplinary programme of research on Islamic glazed pottery, the development of polychrome decoration during the 12th century AD has been investigated by examining polished sections through glazed pottery in an analytical scanning electron microscope. The two main decorative techniques used were underglaze and overglaze painting. The results suggest that true underglaze decoration, involving the application of pigment without any associated slip, was first developed in Syria, from where it spread to Iran, on to China and ultimately across wide areas of the world. In contrast, the overglaze technique used on mina'i ware was both very short‐lived and confined to Iran. The analytical results suggest that the probable explanation for this was the technical problems associated with maturing the overglaze paint and the consequent risk of unsatisfactory products.     

Bone Diagenesis and Taphonomic History of the Paso Otero 1 Bone Bed, Pampas of Argentina

Samples of guanaco bone from an archaeological site in the Pampas of Argentina have been analysed to understand the diagenetic profile of the bone assemblages that characterized the taphonomic history of the site. Two archaeological occupations of Paso Otero 1 were investigated, encompassing similar landscape settings, climates, and depositional environments. The time span is a c. 2000 year period from c. 4800 to 2800 years . A total of 30 bone samples taken from both occupations were used to provide a preliminary characterization of the diagenetic pathways at the site. The parameters investigated provide a comprehensive account of how both mineral (hydroxyapatite) and bone protein (collagen) have been altered. In order to compare the two bone assemblages in terms of their diagenetic parameters, multivariate analyses were conducted. Results indicate two different diagenetic profiles in the site, % N being one of the variables that accounts for most of the variation in Paso Otero 1. The diagenetic analyses indicate that protein is less preserved in the bone assemblage from the middle stable landscape. Alternative interpretations of the diagenetic profiles are discussed in light of the taphonomic history of the site, and palaeoenvironmental information of the region. One hypothesis stresses the importance of the role of climate in defining the different diagenetic pathways, and the other the continued action of the combined diagenetic factors along time as the main explanation for the variability in the state of preservation of the bones in Paso Otero 1.     

COLOURED OPAQUE GLASS BEADS OF THE MEROVINGIANS*

Monochrome coloured opaque glass beads of the Merovingians have been examined by different analytical methods. A large number of mostly unprepared beads have been measured by X‐ray fluorescence analysis. X‐ray diffraction was used for the identification of the crystalline colouring and opacifying pigments, and electron probe micro‐analysis as well as scanning electron microscopy were applied to study the composition and the microstructure of a white, brown, green, orange and yellow glass bead. After subtracting the content of colouring oxides of the glass beads and normalizing the residual values to 100% an identical soda‐lime‐glass matrix was obtained. The origin of the colouring metal oxides is discussed.