Reaping ‘rewards’ in sickle use-wear analysis

Recently in their research Goodale et al. (2010) as well as that of Vardi et al. (2010) independently tackled issues of effectively measuring attrition/gloss rates on sickle blade tools from Southwest Asia. Interestingly, while applying new methodology to analyzing sickle tools from different cultural and temporal contexts, these two papers arrived at a similar conclusion: sickle tools were likely very expensive to make, and thus, considerations were made during their production to ensure long use-lives to benefit the people who made and used them in prehistory. Stemp et al. (in this issue) provide a methodological critique of both studies. In addressing their critique we make several points. First it is important to note that Stemp et al. provide no new experimental analysis to justify their assertions, and their critique is ultimately, at best, guesswork. Second, the minimal reanalysis of the data Stemp et al. do conduct arguably lead to the same preliminary conclusion at which we originally arrived: the prehistoric sickle blades we examined were used longer than those we replicated. As stated in our original paper, lithic use-wear studies often do not address issue of reliable and reproducible methods. We believe that our original study helps fill this missing component, and that measuring edge thickness is much less subjective than conventional features on stone tools traditionally identified microscopically. From our perspective, Stemp et al. present largely unsupported critical commentary, lacking substantial reanalysis or experiments to complement or justify their commentary. In the end Stemp et al. provide little more than interesting ideas and conjecture.     

A method for chronological apportioning of ceramic assemblages

Artifact assemblages from long-inhabited sites may include ceramic types and wares from multiple time periods, making temporal comparisons between sites difficult. This is especially problematic in macro-regional data sets compiled from multiple sources with varying degrees of chronological control. We present a method for chronological apportioning of ceramic assemblages that considers site occupation dates, ceramic production dates, and popularity distribution curves. The chronological apportioning can also be adjusted to take into account different population sizes during the site occupation span. Our method is illustrated with ceramic data from late prehispanic sites in the San Pedro Valley and Tonto Basin, Arizona, U.S.A., compiled as part of the Southwest Social Networks Project. The accuracy of the apportioning method is evaluated by comparing apportioned assemblages with those from nearby contemporaneous single component sites.     

Simulating archaeologists? Using agent-based modelling to improve battlefield excavations

The study of material culture generated by military engagements has created an emergent sub-discipline of archaeological studies centred on battlefields. This approach has developed a particular and sophisticated methodology that is able to deal with the fact that archaeologists will often not find either structures or a useful stratigraphical record on the site, as the material remains of the battle will basically be metallic objects carried by combatants. It is therefore rather complicated not only to test hypotheses about battle events based on archaeological data, but also to validate the methodology used. Here we propose the use of agent-based models to explore these issues in the case of eighteenth-century battlefield archaeology. The simulation is divided into four different steps. Firstly, a battle is simulated in order to generate realistic virtual archaeological remains left by an engagement between two armies of this era. We then simulate the loss of information that the passing of time produces in the battlefield. The third step involves simulating the archaeological survey, enabling us to explore different survey strategies and the impact on the interpretation of the event itself. Finally, we design a confidence index in order to compare the results of the different virtual excavations using spatial analysis and statistics. The results show that the methodology is fully functional in terms of understanding a battle, and it allows us to suggest new strategies to improve fieldwork and to develop new ways of exploring these particular archaeological sites. It is concluded that the described approach illustrates how simulation can be used to explore methodological issues of archaeological science.     

The first direct evidence of pre-columbian sources of palygorskite for Maya Blue

Maya Blue, a nano-structured clay–organic complex of palygorskite and indigo, was used predominantly before the Spanish Conquest. It has fascinated chemists, material scientists, archaeologists and art historians for decades because it is resistant to the effect of acids, alkalis, and other reagents, and its rich color has persisted for centuries in the harsh tropical climate of southern Mesoamerica. One of its components, palygorskite, is part of modern Maya indigenous knowledge, and ethnohistoric and archaeological data suggest that its modern sources were probably utilized in Prehispanic times. Yet no direct evidence verifies that palygorskite was actually mined from these sources to make Maya Blue. Here we characterize these sources compositionally, and compare our analyses to those of Maya Blue from Chichén Itzá and Palenque. We demonstrate that the palygorskite in most of these samples came from modern mines, providing the first direct evidence for the use of these sources for making Maya Blue. These findings reveal that modern Maya indigenous knowledge about palygorskite, its mining, and its source locations, is at least seven centuries old.     

Study of medieval glass fragments from Savona (Italy) and their relation with the glass produced in Altare

Altare was in the medieval and post-medieval period an important glassmaking center in the Liguria region in Northern Italy. The first historical evidence of glassmaking in Altare is dated to the twelfth century. In spite of that, due to the continuity of glassmaking up to the present time and the contemporaneous intensive urbanization of the territory, no medieval glass from Altare or its immediate vicinity has been analyzed up to now. In this work, glass from archaeological excavations in the center of Savona, city with close ties with the glassmaking center, was studied. Glass fragments, dated from the tenth to the sixteenth century were selected from the collections of the Archaeological Museum in Savona and non-destructively analyzed with quantitative PIXE-PIGE. The resulting compositions, compared with known glass productions of the same time and evaluated on the basis of historical documents, offer an interesting panorama on the variety of glass circulation in Liguria.     

Analytical investigation on Renaissance Venetian enamelled glasses from the Louvre collections

Venetian enamelled glass is one of the most significant subjects of the art and technology of Renaissance glassmaking. These items were made in Venice from the second half of the 15th through the 17th centuries and were imitated in other European glassmaking centers during this period and again in Murano during the 19th century. Only a limited number of analyses of these masterpieces have been published up to now.     

The potential of hyperspectral and multi-spectral imagery to enhance archaeological cropmark detection: a comparative study

Aerial photography has made the single most important contribution to our improved appreciation of the density, diversity and distribution of archaeological sites in Britain since World War Two. This is particularly the case for areas of intensive lowland agriculture where ploughed-out sites are known mainly from marks in the crops growing above them. However, reconnaissance for such cropmarks is not equally effective throughout the lowlands, because of the particular conditions of drier weather, well-drained soils and arable agriculture required before they become visible, and is highly unpredictable.     

Non-destructive fabric analysis of prehistoric pottery using high-resolution X-ray microtomography: a pilot study on the late Mesolithic to Neolithic site Hamburg-Boberg

The characterisation of prehistoric pottery fragments presents a quite complex task. In provenance studies, petrographic and chemical analyses of the ceramic materials are employed to investigate potential production areas in respect to the geolocial background. Moreover, also the production technology of the firing process, as well as the forming techniques used by the prehistoric potters are of great interest. Their investigation is most often accompanied by a destructive preparation of the samples. In this paper, we want to present high-resolution X-ray microtomography (μ-CT), a non-destructive and non-invasive method, as a supplementary research tool in the study of prehistoric pottery.