The Ore‐Dressing Grindstone Called a ‘Quimbalete’: a Mechanics‐Based Approach

The ‘quimbalete’ is a kind of grindstone used notably in Potosi (Bolivia) during the Spanish conquest of South America. It was used to grind pieces of ore gravel from centimetric sizes to the size of sand. Its physical functioning, as well as the reason why this strictly Andean tool occupied a central place in a mainly European production chain, have never been addressed. This study is aimed at answering these questions as a result of physics‐based modelling. After introducing the historical context, we address geometrical and physical parameters relevant for understanding how this oscillating grindstone was used and what one can expect in terms of grinding. Then, a suitable approach for estimating the yield makes use of the modern industrial empirical estimator: the ‘power index’. We offer our conclusions about the position of this tool, which appears as an ideal intermediate tool between the roughening process of the ore at the centimetre scale, and the suitable size for the material to be sorted by the subsequent methods in the chain (such as washing), which involve sandy‐sized grains. The study also shows how classical physics can help in addressing questions concerning minerallurgy.     

Portuguese Blue‐on‐Blue 16th–17th Century Pottery

Blue‐on‐blue (‘berettino’) sherds have appeared in numerous production and consumption archaeological excavations in Lisbon and other archaeological sites in Portugal (dated from the mid‐16th century to the beginning of the 17th century). The abundance of this interesting faience led us to compare it with similar pottery from other well‐known production centres in Italy, namely Liguria (Savona and Albisola), Spain (the Triana kilns) and the Low Countries. Differences in the diffraction patterns of the sherds' pastes from the four countries were observed. In most samples, cobalt blue silicate (cobalt olivine) was identified in the dark blue or light blue glazes through the use of micro‐Raman spectroscopy and diffuse reflectance spectra. A remarkable difference in the calcite contents of the Lisbon and Seville pottery sherds was observed, in accordance with previous observations of high calcite contents of Seville ceramics. A comparison was also made for all of the blue‐on‐blue sherds studied here with many other 16th–17th century sherds from Lisbon using bivariate plots of K/Si versus Ca/Si. Lisbon and Seville pottery behave very differently, whereas sherds from Italy and the Low Countries occupy intermediate positions.     

Anglo‐Saxon Style Pottery from the Northern Netherlands and North‐Western Germany: Fabrics and Finish,Regional and Chronological Patterns,and their Implications

This paper presents the results of a study of Anglo‐Saxon style pottery in the northern Netherlands and north‐western Germany, involving macroscopic and microscopic analysis of fabrics and finish. Both regions show similar developments in form and decoration in the pottery of the fourth and fifth centuries ad , the late Roman and Migration period, resulting in the typical decoration and shapes that are known as the Anglo‐Saxon style. In the northern Netherlands, this style is traditionally associated with Anglo‐Saxon immigrants. It has, however, been suggested that this style was, rather, part of an indigenous development in areas in the northern Netherlands where occupation was continuous, though influenced by stylistic developments in north‐western Germany. That hypothesis is supported by the analysis of fabrics and finish presented here. The characteristic of fabrics and surface treatment indicate technological continuity. The use of local clay sources for Anglo‐Saxon style pottery and for contemporary regional types indicates that most of the Anglo‐Saxon style pottery in the northern Netherlands was not brought by Anglo‐Saxon immigrants or as imports, but must have been made locally. That applies to settlements with continuous habitation, as well as settlements in the coastal area that were not inhabited during the fourth century ad .     

The Potential of EBSD and EDS for Ceramics Investigations—Case Studies on Sherds of Pre‐Columbian Pottery

The work focuses on the potential of structural and chemical examinations by scanning electron microscopy based methods for archaeometric studies on ceramics. Achieved by a single preparation technique (polished block sections), the feasibility and benefits of electron backscatter diffraction are demonstrated as case studies using polychrome examples of pre‐Columbian pottery (Wari, Moche and Cajamarca). Elemental and phase maps allow for separate consideration of clay and temper. Identification of mineral phases and intergrowths of temper particles provide information for clarifying clay procurement and firing techniques with respect to local versus non‐local pottery to enlighten trade relations, technological transfer and shared heritage of pre‐Columbian cultures.     

On the Age of Serpent Mound: A Reply to Romain and Colleagues

Radiocarbon dates reported by Romain and colleagues (2017) suggesting that Serpent Mound (33AD1) is an Adena effigy mound are problematic because they cannot be linked reliably to cultural activities associated with the original construction of the effigy mound. Additional arguments offered by Romain and colleagues (2017) in support of an Early Woodland age for Serpent Mound also are unconvincing. A Late Prehistoric age for Serpent Mound is supported by the radiocarbon dates reported previously, new radiocarbon dates, the relative abundance of serpent imagery in the Fort Ancient culture and the contemporaneous Mississippian Tradition, the virtual absence of serpent imagery in the Adena culture, and the fact that, whereas effigy-mound building is otherwise unknown in the Early Woodland period, it is well documented, if rare, for the Fort Ancient culture and in the not-so-terribly-far-away upper Midwest it is so common that it defines the broadly contemporaneous Effigy Mound culture.     

The first discovery of Neolithic rice remains in eastern Taiwan: phytolith evidence from the Chaolaiqiao site

Located in the key junction between mainland China and Island Southeast Asia, Taiwan is of great significance for our understanding of the southeastward dispersal of rice agriculture in the prehistoric period. Until now, quite limited archaeobotanical work has been done in this region. In eastern Taiwan, no archaeological evidence of rice agriculture has been obtained, probably owing to the poor preservation conditions for plant macroremains. Here, we report a new discovery of 4200-year-old domesticated rice remains at the Chaolaiqiao site, which for the first time in detail demonstrates the ancient practice of rice agriculture in this area. Based on a combination of factors that include a rice-based plant subsistence strategy, the mid-Holocene limits to available farmland and the fast-growing Taiwan Neolithic population from settlement pattern data, we infer that this contradiction in eastern Taiwan between land-dependent agriculture and limited suitable farmland encouraged a population movement out of Taiwan during the Middle Neolithic period.     

Exploring a Bayesian method for examining the regional ceramic sequence along the Georgia Coast

This report presents an exploratory Bayesian modeling program of a recently compiled radiocarbon database for the Georgia Coast. Through use of the region’s well-established ceramic sequence as the a priori modeling framework, a refined temporal sequence for the region is presented. The model demonstrates gaps in the radiocarbon record between the Late Archaic and Refuge periods, the Deptford and Wilmington periods, and the Wilmington and St. Catherines periods. The model also suggests that the Savannah period wholly subsumes the St. Catherines period. Although biases exist based on the nature of the radiocarbon database utilized, the model demonstrates the utility of reinvestigating regional chronological sequences as well as the use of legacy radiocarbon data.     

Multi-method Analysis of Avian Eggs as Grave Goods: Revealing Symbolism in Conversion Period Burials at Kukruse,NE Estonia

Eggshells are unusual finds in the Iron Age of eastern Europe (500 BC–1200 AD) deserving extra attention in terms of analysis as well as interpretation. This paper discusses two rare eggshell finds, discovered in female burials at the conversion period (12th–13th century AD) cemetery at Kukruse, NE Estonia. Our multianalytical study combining FT-IR, SEM(-EDS), microscopy and ZooMS provides an overview of methods applicable for identifying egg species, their predepositional history and curation. Based on the analytical results and the comparative analysis of the content and context of these two burials, we argue that different aims and connotations lay behind depositing eggs as burial goods, allowing well-supported interpretations of both pagan and Christian religious worldviews simultaneously.     

A THERMAL METHOD FOR ARCHAEOLOGICAL PROSPECTION: PRELIMINARY INVESTIGATIONS

Interaction of archaeological features with the secular variation in surface heat flux generates an anomalous ground temperature distribution which can form the basis for a shallow geophysical prospecting tool. Earlier studies have concentrated on recording surface temperature disturbances via aerial thermography but these results can be biased towards minor variations in vegetation, albedo. and microclimate. A more promising approach is to record temperatures at a depth of 20cm using a simple probe. Anomalies at this depth arise from the interaction of objects with the annual heat-flux cycle and other long-term temperature variations. The amplitude, shape, and phase of anomalies have been modelled, together with the nature and magnitude of other, unwanted causes of ground temperature variation. Field equipment and data processing techniques for the direct-contact approach to thermal prospection have undergone trails in the U.K. at Verulamium and Fountains Abbey.