Study of a Late Bronze Age Casting Mould and Its Black Residue by 3D Imaging, pXRF, SEM-EDS, Micro-FTIR and Micro-Raman

In the present work, a fragment of a stone mould recently found in Galicia (NW Spain) was studied by multiple analytical techniques approach involving 3D optical imaging reconstruction to obtain data about the shape of the mould, typology of artefact produced, and distribution of a black residue at the surface of the mould and pXRF, SEM-EDS, micro-FTIR, and micro-Raman to investigate the nature of the black residue. The study shows that the mould was likely used for socketed axes with a side loop, was originally composed of two valves and one core, and that it might have been subjected to a repair during use. The black residue is distributed in the carved surface and spreads to nearby surfaces as a result of the use of the mould. The alloy cast in the mould was a ternary bronze (Cu + Sn + Pb). The analyses by SEM-EDS of black residue covering the surface did show the presence of scattered micro particles with P and Ca, and micro-Raman analysis detected the presence of a carbon black of animal source, while micro-FTIR analysis detected remains of proteins, oxalates, and hydroxyapatite. These results are amongst the very few studies made on black residues of ancient moulds and suggest that the mould was dressed with a carbon black of animal origin, such as burned bones, prior to metal casting, probably used as a coating agent to improve the casting and artefact recovery.

Profiling of human burned bones: oxidising versus reducing conditions

Complementary optical and neutron-based vibrational spectroscopy techniques (Infrared, Raman and inelastic neutron scattering) were applied to the study of human bones (femur and humerus) burned simultaneously under either aerobic or anaerobic conditions, in a wide range of temperatures (400 to 1000 °C). This is the first INS study of human skeletal remains heated in an oxygen-deprived atmosphere. Clear differences were observed between both types of samples, namely the absence of hydroxyapatite’s OH vibrational bands in bone burned anaerobically (in unsealed containers), coupled to the presence of cyanamide (NCNH2) and portlandite (Ca(OH)2) in these reductive conditions. These results are expected to allow a better understanding of the heat effect on bone´s constituents in distinct environmental settings, thus contributing for an accurate characterisation of both forensic and archaeological human skeletal remains found in distinct scenarios regarding oxygen availability.

Medieval Sites of Tara Region, the Irtysh Basin: Origin, Chronology, Cultural and Ethnic Attribution

We describe 17 medieval kurgans at Murlinka, dating to the late 1st millennium AD and associated with archaeological sites at Aitkulovo, in the Tarsky District of the Omsk Region, on the right bank of the Irtysh, in the borderland between the forest-steppe and the taiga. The deceased were buried in a supine extended position. Some burials were made on the virgin soil, and some on the buried soil. Most kurgans accommodated one grave, but in some cases the number of graves was two and more. Inside the kurgans, at the buried soil level and above, limb bones of animals and small potsherds were found. In certain graves, traces of fi re, such as partly burned bones, charcoal, ash, or charred earth, were detected. We also found ditches and various structures inside the mounds. In eleven mounds, there were funerary offerings, such as vessels, arrowheads, celts, bits, and ornaments, similar to those found in the graves. We give a detailed description of bronze ornaments and pommels, tools, and belt sets made of white metal, as well as glass and ceramic beads, iron artifacts, details of horse harness, iron and bone weapons, and pottery. Parallels are found in the taiga regions of the Middle Ob, Ural, and the steppe zone of northern Altai. We discuss the chronology and cultural attribution of the fi nds in the context of the ethnic processes that occurred in the region.

INVESTIGATION OF THE EARLY IRON AGE MOUNDS IN THE BASIN OF THE ROS RIVER

The paper is devoted to the publication of materials of two early Iron Age burial mounds in Porossya on the territory of the Dnieper Right Bank Forest-Steppe. Monuments were located near the Lysa Gora natural boundary and the village Novoselytsya near Tarascha. Small barrows with a height about 0.5—0.65 m and a diameter near 10—14 m contained burials in rectangular graves with a small entrances. Above on them the special ground areas were constructed, then they were covered with a mound. The burial ceremony could be either incomplete cremation on the site of the mound, or the secondary burial of burned bones. Complexes can be dated by the pre-Scythian time or the beginning of the early Scythian period, and belong to the local settled population.

Hearths in the coastal areas of northernmost Sweden, from the period AD 800 to 1950

This paper presents a study of the chronological setting of hearths registered in FMIS (digital register containing records of all known ancient monuments in Sweden) in the provinces of Västerbotten and Norrbotten, Northern Sweden. A total of c. 1500 hearths are known in the area, mainly situated north of the river Skellefteälven. Within a study area of 107 x 94 km, 32 hearths were randomly selected for excavation, each site embracing 1-14 hearths. The sites were scanned using a metal detector and nearly all artifacts found were from the period AD 1600-1900. 14C-datings of charcoal and burned bones corroborated that most hearths were used during this period, with a large number dating to the 19th and 20th centuries. Many hearths contained bones from mature reindeer, indicating that the hearths were related to reindeer herding. We suggest that most hearths are related to nomadic Sami reindeer herders using coastal areas for winter pasture, possibly resulting from the breakdown of the “lappskatteland” (taxation lands) system and an increase in reindeer numbers.

Understanding the Crystallinity Indices Behavior of Burned Bones and Teeth by ATR-IR and XRD in the Presence of Bioapatite Mixed with Other Phosphate and Carbonate Phases

We have critically investigated the ATR-IR spectroscopy data behavior of burned human teeth as opposed to the generally observed behavior in human bones that were subjected to heat treatment, whether deliberate or accidental. It is shown that the deterioration of the crystallinity index (CI) behavior sometimes observed in bones subjected to high temperature appears to be of higher frequency in the case of bioapatite from teeth. This occurs because the formation of the β-tricalcium phosphate (β-TCP) phase, otherwise known as whitlockite, clearly ascertained by the X-ray diffraction (XRD) patterns collected on the same powdered specimens investigated by ATR-IR. These results point to the need of combining more than one physicochemical technique even if apparently well suitable, in order to verify whether the assumed conditions assessed by spectroscopy are fully maintained in the specimens after temperature and/or mechanical processing.