Chert raw materials and artefacts from NE Bulgaria: A combined petrographic and LA-ICP-MS study

Abstract

Abstract:In the present study two analytical methods are applied to characterize chert artefacts and raw materials from northeastern Bulgaria (Ludogorie region): petrographic observation and laser ablation inductively coupled plasma mass spectrometry). Archaeological samples from 12 Chalcolithic sites from Bulgaria are analyzed as well as raw material from 6 outcrops in northeastern Bulgaria are identified and documented during a survey in 2012 when many raw material samples were collected. The chert raw material mostly occurs in various Quaternary secondary deposits, originating from destruction and disintegration of the Lower Cretaceous (Aptian) limestones in the area. The paper is aimed at tracing the provenance of the artefacts based on their petrographic characteristics and geochemical composition. The archaeological evidence shows a wide distribution of the Ludogorie chert throughout the country.On the basis of micropetrographic observations, Gurova and Nachev (2008) described two main chert types (Ravno and Kriva Reka). Our petrographic study confirmed the previous results and an additional chert type was distinguished, originating from primary and secondary deposits (quarries in Koprivetz and Krasen villages) and is represented by silicified limestones (bioclastic-peloidal packstones or grainstones). It is noteworthy that the first two types of chert were largely used for prehistoric artefact manufacturing while the last one is not attested among studied assemblages at all.

The “Flint Depot” of prehistoric northern Israel: Comprehensive geochemical analyses of flint extraction and reduction complexes and implications for provenance studies

“…The nondestructiveness of LA‐ICP‐MS has rendered the method a first choice in many geochemical studies (see, e.g., studies presented in Pereira et al, ) and the only choice when dealing with museum collections. However, it is hampered by its sensitivity to the relatively high heterogeneity of flint and to the debatable effects of patination, which are usually compensated for by trying to represent fully natural heterogeneities that appear on the item’s outer parts (Andreeva, Stefanova, & Gurova, ; Brandl et al, ; Gurova et al, ; Moreau et al, ; Moroni & Petrelli, ; Pettitt, Rockman, & Chenery, ; Speer, ). This still does not guarantee a reliable representation of the composition of a complete object, as inner parts of the object may contain other concentrations of elements than the outer parts.…”

Petrographic and SEM‐EDX characterization of Mousterian white/beige chert tools from the Navalmaíllo rock shelter (Madrid, Spain)

“…Complementary methods of analysis are required to make reliable comparisons of artefacts and to determine the geological areas from which they might have come. Multiple complementary methods should be used, taking into account the relationship between cost, time and the results that can be obtained (Andreeva et al, 2014; McDonnell et al, 1997; de la Torre et al, 2017).…”

“…Fortunately, nondestructive methods that require no specialized sample preparation have recently become available (Campbell & Healey, 2016; Carvalho & Pereira, 2017; Constantinescu, Bugoi, & Sziki, 2002; Eixea et al, 2014; Frahm, 2014; Nadooshan, Abedi, Glascock, Eskandari, & Khazaee, 2013; ten Bruggencate, Fayek, Brownlee, Milne, & Hamilton, 2013), though individually these methods have limitations. The detailed characterization of raw lithic materials, and therefore the identification of sourcing areas, requires complementary methods to be employed (Andreeva, Stefanova, & Gurova, 2014; McDonnell, Kars, & Jansen, 1997; de la Torre et al, 2017). The determination of raw material sourcing areas allows us to establish resource exploitation strategies and mobility patterns during Prehistory.…”

Flint sources and mobility at the Chalcolithic (3500–2200 BCE) settlement of Zambujal (Portugal)

“…Laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) may be a possibility because it is a highly sensitive method and can detect a wide range of elements at low concentrations. Geochemical sourcing has had good results when combined with petrography (e.g., Andreeva et al, 2014; M. Carvalho, 2001; Fernandes et al, 2019; Sánchez de la Torre et al, 2017).…”