A Little Bit of Dirt

An examination of the surface deposit of an Etruscan cup said to have been dug up in Cheshire suggests instead that it had been buried in Italy and brought to England in recent times. The method described here might usefully be employed to assess the provenance of buried artefacts.     

The Material Characterization of a Santamarian Ceremonial Axe

The characterization of a ceremonial bronze axe is described. The axe is assigned to the Santamarian culture of north‐west Argentina, c. 1000–1470 ad, and was selected to increase presently limited knowledge of prehistoric metallurgy in the Andean region of Argentina. The characterization methods used were electron probe microanalysis, gamma radiography, X‐ray diffraction, optical metallography and microhardness testing. The axe was well cast in a bivalve mould, with the only defects in the area of an ancient fracture. The analysis showed that it is made from a tin bronze with a, probably, accidental addition of lead. Arsenic was found as a surface contamination, probably deriving from arsenic in the water of the stream in which the axe was found. The axe shows that Santamarian craftsmen had the skill to decorate the axe in an artistic style with a strong local accent while providing a functional, annealed and cold‐worked cutting edge.     

OPTICAL DATING OF GRANITIC STONE SURFACES*

A novel luminescence methodology for dating surfaces of granitoid rocks is presented, with encouraging results for archaeological stone structures. It is based on the zeroing of the latent signal of optically stimulated luminescence (OSL) in feldspar and quartz grains of the stone surface during exposure to daylight. When after bleaching the surface is shielded from light, the OSL signal builds up again, such that its intensity provides an age for the event of the last exposure to light. This event could be the construction or the destruction of stone structures or, for example, sedimentary deposition of granitic boulders, such as in fan deposits. The experimental approach utilizes a high spatial resolution detection technique (HR‐OSL) for OSL of minerals that are left in their original petrological context; that is, without any mineral separation. With this approach, steep gradients in microdosimetry at the surface and at grain boundaries become important and are discussed in detail. The new dating technique is successfully applied to a stone wall of the medieval castle of Lindenfels in southwestern Germany and the pre‐Columbian Nasca lines (geoglyphs) around Palpa in southern Peru.     

GEOCHEMICAL AND ENGINEERING GEOLOGICAL PROPERTIES OF THE VOLCANIC TUFFS USED IN THE ETRUSCAN TOMBS OF NORCHIA (NORTHERN LATIUM,ITALY) AND A STUDY OF THE FACTORS RESPONSIBLE FOR THEIR RAPID SURFACE AND STRUCTURAL DECAY

The geochemical and engineering geological properties of the tuffs used in the rock‐cut cliff tombs of the Etruscan necropolis of Norchia were investigated to evaluate their susceptibility to different weathering agents and confirm their origin. For the first time, materials were characterized by X‐ray powder diffraction (XRD), Fourier‐transform infrared spectroscopy (FT–IR), thermogravimetric analyses (TGA, DGA and DTG), scanning electron microscopy (SEM–EDS) and energy‐dispersive X‐ray fluorescence (ED–XRF), and their different origins confirmed. Tests of material properties indicate that both tuffs are poorly durable, but one of them is less susceptible to weathering. Although tombs made with the more resistant material show limited surface weathering, they undergo severe structural damage because of stress release and plant root infiltration. This, combined with the microclimatic conditions established inside river canyons, can trigger rock falls, leading ultimately to the complete destruction of these tombs.     

ROCK SURFACE HARDNESS AS AN INDICATION OF EXPOSURE AGE: AN ARCHAEOLOGICAL APPLICATION OF THE SCHMIDT HAMMER*

A Schmidt Hammer was employed in evaluating the surface hardness of rocks which line ancient anthropogenic pit features, known as Pukaskwa pits, on the north shore of Lake Superior, Canada. This technique offers a possible new method of producing relative ana absolute dates for such exposed stone features Analysis of the data has provided a relative chronology for the pit features, representing two distinct construction phases. The range of absolute dates generated from the data indicates that the pits were likely constructed by Blackduck peoples c. 900 to 400 years BP.     

Long-Term Occupation and Seasonal Settlement of Eastern Eurasian Pastoralists at Begash,Kazakhstan

Abstract

Recent excavations of the prehistoric pastoralist settlement of Begash, located in the Semirech'ye region of eastern Kazakhstan, provide evidence of one of the earliest pastoralist settlements in the eastern Eurasian steppe region. The archaeological complex at Begash includes a multi-period cemetery and rock art in addition to the settlement—a site complex that is well distributed throughout the koksu River Valley. Excavations at Begash have revealed three major phases of architectural development and six phases of material transition and site use, dated by a series of 34 calibrated radiocarbon AMS dates. These data demonstrate that mobile pastoral populations were active in the Dzhungar Mountains and koksu River Valley (Semirech'ye) as early as 2460 CAL B.C., more than 800 years earlier than previous theories suggested. Pastoralist activity at this domestic locale spans nearly 4000 years, with no archaeological evidence for long-term abandonment of the site in prehistory. Rather the occupational phases of the site are only interrupted by short-lived periods of disuse followed by centuries of re-engagement by local pastoralist communities. Thus, the broadly continuous record of material culture, domesticated faunal remains, and settlement at Begash index a local evolution of herding economies in Semirech'ye throughout the Bronze Age, beginning in the middle part of the 3rd millennium B.C. Ultimately, the data from Begash contribute a new perspective on the dynamic nature of Eurasian mobile pastoralists while also illustrating broad continuity in the settlement ecology of local populations that had a key role in the regional transmission of numerous innovations throughout the Bronze Age and later.     

Early Copper Age Settlements in the Körös Region of the Great Hungarian Plain

Abstract

This article discusses research carried out by the Körös Regional Archaeological Project from 2000 to 2006 at Early Copper Age Tiszapolgár Culture sites on the Great Hungarian Plain. To build a model of social organization for the period, we incorporated information from regional geomorphological studies, soil chemistry analysis, archaeological surface surveys, remote sensing, and systematic excavations at Early Copper Age sites in the Körös Valley of southeastern Hungary. Previous models characterized the transition from the Neolithic period to the Copper Age as an abrupt shift from a tell-based, sedentary, agricultural lifeway to one based on mobile cattle herding. By studying the transition between these periods on multiple geographic and temporal scales, we have identified a more gradual process with widespread regional variation in cultural patterns. Similar social processes characterize the transition between chronological periods and cultural phases in other parts of the world, and we suggest that a multiscalar approach is effective for building comparative archaeological models of long-term social change.     

AN ASSESSMENT OF COMPOSITIONAL AND MORPHOLOGICAL CHANGES IN MODEL ARCHAEOLOGICAL GLASSES IN AN ACID BURIAL MATRIX

The degradation mechanisms of glass in a buried context result in surfaces that have been depleted in various elements. The stability of the glass is primarily affected by the burial environment and the glass composition. However, in all archaeological glasses, the corroded layer that is formed on the surface tends to be low in alkalis, high in silica and lacking in cohesion. The extent to which the material has degraded, along with the physical nature of the corrosion, has a profound effect upon a wide range of factors affecting the stability of artefacts, as well as the choice of conservation techniques to be employed. This study has a number of objectives: determination of the morphology of the surface of the leached layer in glasses of two different compositions with different surface finishes; examination of the transition between the corroded material and the unaffected substrate; and investigation of concentration profile of different elements within the surface layers, as a function of depth. The study uses two glasses, fabricated under laboratory conditions, to replicate two common glass types found in the historical environment; a soda–lime–silica glass typical of those found in the Roman period throughout the Mediterranean and northwestern Europe, and high‐lime–potash glasses typical of those of Western Europe in the late medieval period. Three different surfaces have been prepared to mimic alternative manufacturing techniques such as blown, cast and ground surfaces for each composition. The glasses have been corroded under controlled laboratory conditions to replicate the buried environment. Imaging and chemical information is obtained using SEM–EDX and morphological information using IFM to produce 3‐D mapping from topographical surfaces.     

GLASS CORROSION ACROSS THE ALPS: A SURFACE STUDY OF CHEMICAL CORROSION OF GLASSES FOUND IN MARINE AND GROUND ENVIRONMENTS*

Ancient glasses deriving from differing environments (marine and ground) and areas (Mediterranean and Continental) have been investigated to understand their weathering processes. Although the glass technologies, developed in various ways, and the differing compositions of the glasses from the two areas, have generated differing durabilities, the weathering features of both typologies of glass are identical. Therefore, the corrosion phenomena are due to the action of water, and they are not related to the sample microclimate. Data have been collected using optical microscopy, RGA and surface analysis techniques: XPS, ESEM and SIMS.