Raspadita: a new lithic tool from the Isthmus of Rivas,Nicaragua

A new lithic tool type was discovered at the Pacific Nicaraguan archaeological site of Santa Isabel (AD 800–1350) and named raspadita (small scraper). Thousands of these small tools (1–2 cm in length) were found. They have a rounded proximal edge and a pointed distal end. In this study, the raspaditas are proved to be a coherent tool class with minimal variation in size, shape, material type and usewear. They were manufactured from white chert bladelet cores using soft hammer percussion and pressure flaking unifacial retouch. Usewear points to a composite tool form and a scraping function for the raspaditas. Scanning electron microscopy determined a ventral leading, dorsal following, unidirectional scraping motion for the raspadita proximal end. The material that was scraped has still to be definitely determined but phytoliths visible in the SEM images suggest that the composite tool was used for plant processing.     

Assessing XRF for the geochemical characterization of radiolarian chert artifacts from northeastern North America

The purpose of this paper is to emphasize the benefits of adopting non-destructive energy dispersive X-ray fluorescence (ED-XRF) as a first-order technique to determine chert whole-rock geochemistry for archaeological sourcing. Chemical signatures for the Touladi and La Martre prehistoric quarries from the lower St. Lawrence and Gaspé Peninsula region of Quebec, Canada, are determined and serve as references to test the provenance of regional chert artifacts. Chert experimental flakes, created from quarry geological hand samples, are analyzed and used to validate the method. Archaeological flakes and tools recovered from three archaeological sites are analyzed and tested against quarry samples. Geochemical diagrams and Principal Component Analysis are used to establish artifact-quarry relationships. The effects of surface weathering on the geochemical analysis of archaeological chert artifacts are presented. Sample restoration and research avenues are discussed and proposed to further enhance the robustness of future chert geochemical data sets.     

Vein quartz in lithic traditions: an analysis based on experimental archaeology

Worldwide, vein quartz was a commonly used raw material for stone tools but this material has proved difficult for archaeologists to analyse because many quartz assemblages appear to be comprised of amorphous pieces, not easily recognised as humanly modified or forming ‘tools’. This paper discusses the analysis of the debitage – focusing on the debitage fragmentation rate, the debitage, break, and fragment types, and the quantitative analysis of the complete flakes – resulting from experimental knapping of quartz, which formed part of a project which investigated the use of quartz in Irish prehistoric lithic traditions. The results have highlighted the complexity involved in analysing quartz assemblages, and the significant differences between the debitage products of quartz and chert knapping assemblages. While bipolar knapping is generally easy to differentiate from direct percussion, it is harder to differentiate between soft and hard hammer percussion.     

Non-destructive provenance study of chert using infrared reflectance microspectroscopy

In this paper we explore the potential of non-destructive Infrared reflectance microspectroscopy (IRRMS) for the characterization of chert samples from 10 different geological outcrops in North America with emphasis on the Midcontinent. A principle objective of the project is to determine whether IRRMS analysis can provide a mineral-based signature for bedrock sources of chert artifacts. The technique utilizes a Bio-Rad Digilab FTS-40 Infrared spectroscope and microscope attachment that reflects an infrared beam off a chert specimen. Our findings indicate that spectral features from the molecules constituting minor and trace minerals in chert may provide sufficient characterization for chert sourcing.     

A pilot study of “black chert” sourcing and implications for assessing hunter-gatherer mobility strategies in Northern England

Mesolithic hunter-gatherer logistic strategies and raw material procurement locales have been topics of considerable interest in northern England, accelerated by the early discoveries at Star Carr. Here we present the results of a pilot study investigating the potential for geochemically sourcing “black chert”, a material with similar qualities to flint but of inland limestone origin, using ICP-AES, ICP-MS and LA-ICP-MS. Several geological sources of black chert are known, and it is commonly present at upland Mesolithic sites along the Pennine chain. Four geological sources were sampled and analysed, along with a small sample of black chert artefacts from two upland Pennine archaeological sites. The results demonstrate that the four sampled sources can be easily differentiated from one another chemically. This research reveals the potential to apply this approach at a larger scale; the archaeological sample together with the source results indicate that additional sources will need to be identified and sampled before such data can be applied to address current questions of the Mesolithic of northern England.