The allure of rock crystal in Copper Age southern Iberia: Technical skill and distinguished objects from Valencina de la Concepción (Seville, Spain) (2022)

Table of Contents
Quaternary International Abstract Introduction Section snippets Contexts Core and micro-blades Geochemical characterisation Singularity of the technological process Acknowledgements References (110) Journal of Archaeological Science Objects in exotic raw materials and the hierarchical structure of the tombs in the Los Millares necropolis (Santa Fe de Mondújar, Almería, Spain) El puñal de sílex calcolítico de La Garma (Omoño, Cantabria). Sautuola Revista del Instituto de Prehistoria y Arqueología Sautuola El Poblado y la Necrópolis Megalíticos de Los Millares (Santa Fe de Mondújar, Almería) Más allá de la tipología lítica: lectura diacrítica y experimentación como claves para la reconstrucción del proceso tecnológico Contemporary rock crystal mining in Minas Gerais, Brazil: an ethno-archaeological case study Los Dólmenes de Valencia de Alcántara El Fenómeno Megalítico en Andalucía Occidental Marine bioerosion in rocks of the prehistoric tholos of La Pastora (Valencina de la Concepción, Seville, Spain): archaeological and palaeoenvironmental implications Journal of Archaeological Science El dolmen de Ontiveros (Valencina de la Concepción, Sevilla) El dolmen de Hidalgo (junto a la desembocadura del Guadalquivir) y las contiguas sepulturas en fosa eneolíticas Les cristaux de roche du tertre et de la tombe Los sepulcros megalíticos de Huelva. (Excavaciones arqueológicas del Plan Nacional 1946–1952) Exemples tourangeaux de sciage des roches au Néolithique Bulletin de la Société Préhistorique Française The Copper Age settlement of Valencina de la Concepción (Seville, Spain): demography, metallurgy and spatial organization Trabajos de Prehistoria Artefacts produced in rare rocks from funerary contexts of the 4th–2nd millennia cal BCE in southern Spain: a review Craft specialization: issues in defining, documenting and explaining the organization of production Craft production systems The mechanics of flaking Mesoamerian polyhedral cores and prismatic American Antiquity Le Sciage des Roches Tenaces au Nord-Ouest des Alpes (4300–2450 av. J.-C.) Précis de Dessin Dynamique et Structural des Industries Lithiques Préhistoriques Lithic resources in the early prehistory of the Alps Archaeometry Soto, un ejemplo de arte megalítico al Suroeste de la Península Aplicación de las técnicas mineralógicas y petrológicas a la arqueometría: Estudio de materiales del Dolmen de Alberite (Villamartín, Cádiz) Zephyrus Productos arqueológicos exóticos en los contextos de los yacimientos prehistóricos de la banda atlántica de Cádiz. Inferencias de su documentación Practical Raman spectroscopy El Chamanismo y las Técnicas Arcaicas del Éxtasis Enterramientos de la Edad del Bronce del Cerro del Berrueco (Medina Sidonia, Cádiz) Pyrenae Los prismas de cuarzo en la cultura megalítica del Noroeste de la Península Ibérica Brigantium Gestión del cuarzo y la pizarra en el Calcolítico peninsular: el santuario de El Pedroso (Trabazos de Aliste, Zamora) Trabajos de Prehistoria Montelirio: Un sepulcro clave para la comprensión del registro de los grandes monumentos megalíticos de Valencina de la Concepción-Castilleja de Guzmán (Sevilla) Avance al estudio del sepulcro megalítico de la Cuesta de los Almendrillos de Ardite, Alozaina (Málaga) Apalaeodietary study of stable isotope analysis from a high-status burial in the Copper Age: the Montelirio megalithic structure at Valencina de la Concepción-Castilleja de Guzmán, Spain International Journal of Osteoarchaeology Production and Exchange of Bifacial Flaked Stone Artifacts during the Portuguese Chalcolithic El cuarzo como material votivo y arquitectónico en el complejo funerario megalítico de Palacio III (Almadén de la Plata, Sevilla): análisis contextual y mineralógico Trabajos de Prehistoria Sacred work: dedication and termination in Mesoamerica Une approche anthropologique de la notion de bien de prestige. Bulletin d'Études Préhistoriques et Archéologiques Alpines (Aoste) 21 Las mineralizaciones de litio asociadas al magmatismo ácido en Extremadura y su encuadre en la Zona Centroibérica El asentamiento de la Edad del Cobre de Valencina de la Concepción: estado actual de la investigación, debates y perspectivas Social complexity in Copper Age southern Iberia (c. 3200–2200calBC): reviewing the ‘state’ hypothesis at Valencina de la Concepción (Seville, Spain) Ivory craftsmanship, trade and social significance in the southern Iberian Copper Age: the evidence from the PP4-Montelirio sector of Valencina de la Concepción (Seville, Spain) European Journal of Archaeology El sepulcro megalítico del Cortijo de la Mimbre (Alpandeire-Málaga) Baetica Excavaciones en Niebla (Huelva): El Tholos de El Moro El Lenguaje de la Diosa Le travail de la fibrolite en Armorique Bulletin de la Société Préhistorique Française Torre Melgarejo, un sepulcro de inhumación colectiva en los Llanos de Caulina (Jerez, Cádiz) Memoria y mapa geológico y de recursos minerales del sector centro-occidental de Extremadura (escala 1:100.000) Un avance de la excavación del sepulcro megalítico de El Juncal (Ubrique, Cádiz) Revista Atlántico Mediterránea de Prehistoria y Arqueología Social Cádiz Cited by (10) Crafting Idiosyncrasies. Early Social Complexity, Ivory and Identity-Making in Copper Age Iberia A Prehistoric Rock Crystal Procurement Site at Fiescheralp (Valais, Switzerland) A New Perspective on Copper Age Technology, Economy and Settlement: Grinding Tools at the Valencina Mega-Site Fluorite and translucent beads in Iberian Late Prehistory Recommended articles (6)
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Quaternary International

Volume 424,

7 December 2016

, Pages 232-249

Abstract

Rock crystal appears relatively frequently in Late Prehistoric Iberian sites, especially in the form of micro-blades and knapping debris. With some exceptions, however, these finds have seldom been looked into in any detail, and therefore little is known about the technology involved in the use of this material, its social and economic relevance or its symbolic significance. In this paper we examine a collection of rock crystal artefacts recently found at Valencina de la Concepción (Seville, Spain), one of the largest 3rd millennium BC sites in Western Europe. Among the objects included in this study are a long dagger blade, twenty-five arrowheads and a core, all of which form the most technically sophisticated and esthetically impressive collection of rock crystal material culture ever found in Prehistoric Iberia. Through the analysis of the procedures and techniques applied in the production of these objects, the chemical characterisation of the raw materials through Raman spectroscopy and RTI image processing and the careful assessment of the archaeological contexts in which they were found, this paper makes a robust contribution towards the study of the role of rock crystal in Copper Age technology and society. Recent research suggest that Valencina was a major node in the circulation of exotic materials such as ivory, amber, cinnabar or flint in Copper Age Iberia, which provides a very good background to assess the relevance of rock crystal as a traded commodity. In addition we discuss the role of rock crystal as a marker of status in large megalithic monuments, as well as its possible symbolic connotations.

Introduction

In prehistoric Europe, lithic utensils were largely made from varieties of cryptocrystalline sedimentary rock or other rocks with conchoidal fracture. Knapping of minerals such as rock crystal was less prevalent, due to their anisotropic structure. The term ‘rock crystal’ is applied to a monocristal which is as variety of macro-crystalline quartz characterised by its hyaline appearance and ordered atomic structure, which determines specific knapping methods, following its internal structure (Crabtree, 1968: 10–11; Novikov and Radililovsky, 1990, Mourre, 1994, Inizan etal., 1999: 19–23). In some European regions the exploitation of rock crystal may have been caused by the dearth of flint (Aubry and Igreja, 2009), although it has been observed that its exploitation could also be explained by its physical properties and symbolic value (Reher and Frison, 1991, Taçon, 1991, Sachanbiński etal., 2008). The limitations inherent to the manufacture of rock crystal objects in comparison with objects made from other raw materials are reflected in the reduced size of the knapped objects, their low level of standardisation and the particular features of the chaîne opératoire involved – including the frequent use of uncontrolled knapping on an anvil (Peña and Wadley, 2014). Nonetheless, a technique for working with rock crystal which overcame the aforementioned limitations was developed during Late Prehistory in certain European regions. This was the case of the south-west of the Iberian Peninsula in the third millennium BCE.

Not as much research into the use of rock crystal in Iberian Late Prehistory has been carried out as into other exotic materials, such as variscite, ivory and amber. Since the 1980s a handful of articles (for example Fábregas Valcarce, 1983, Fábregas Valcarce and Rodríguez Rellán, 2008, Forteza González etal., 2008) as well as numerous references in excavation reports and studies of lithic technology have noted the importance of this raw material. However, it was not until a recent synthesis was published (Costa Caramé etal., 2011) that we began to acquire a general idea of its importance in the fourth and third millennia BCE, a period in which it was valued particularly highly and would seem to have been very socially significant. According to this synthesis, in the Spanish southwest (regions of western Andalusia and Extremadura - a territory with an area of 129,902km2) rock crystal items have been found in 33 different structures, mostly megalithic monuments (Table1, Fig.1). Some items came from tombs of the same necropolis. For a further five sites, items more vaguely described as “quartz crystals” (and others) are mentioned that could allude to rock crystal (Costa Caramé etal., 2011). The vast majority of these structures only contained one or two objects, with a few exceptions, such as the dolmens of Lanchas I (Valencia de Alcántara, Cáceres), El Corchero (also in Valencia de Alcántara), and Ontiveros (Valencina de la Concepción, Seville), in which 15, 12 and 16 arrow heads were found respectively, as well as the Cuesta de Los Almendrillos megalith (Ardite, Málaga), from which 10 micro-blades were collected. From a functional viewpoint, rock crystal appears in these contexts either in its natural form, with very little or no processing (which is the case with nodules, monocrystals and prisms), as arrowheads or, more commonly, as micro-blades and small extraction cores (Costa Caramé etal., 2011: 261). The only exceptions to this general rule are two perforated beads from Los Millares (Almería) and two more from Las Lanchas I and Datas II megaliths respectively (both belonging to the megalithic site of Valencia de Alcántara, in Cáceres). This suggests that in Iberian Late Prehistory there were well defined patterns for selecting raw materials according to the use or function they would be given. Stones such as variscite and amber seem to have been exclusively used to make body ornaments, whereas rock crystal was predominantly used to manufacture arrowheads and micro-blades, although quartz monocrystals and prisms were used in their ‘natural’ state, perhaps as personal, apotropaic objects (such as amulets or charms). In the Palacio III megalithic funerary complex (Almadén de la Plata, Seville), a set of monocrystals, prisms and nodules of various types of quartz, which had not been (or hardly had been) processed, were identified: they were interpreted as amulets, talismans, charms or even heirlooms (Forteza González etal., 2008). The only piece of rock crystal in the Palacio III burial complex was a micro-blade (Forteza González etal., 2008).

The empirical evidence regarding the provenance of the rock crystal and quartz found in these megalithic monuments is very scarce. We can mention the analysis of the magnificent smoky quartz monocrystal found in the dolmen of Alberite (Villamartín, Cádiz), for which a non-local origin connected with the pegmatite rock deposits located in the igneous massifs of the Spanish Central System was suggested (Domínguez-Bella and Morata Céspedes, 1995: 141). In the Palacio III megalithic complex, the monocrystals found in the tholos (ornaments 4 and 5) were both classified as belonging to the milky variety, which is translucent (i.e. not transparent and with white colour), and interpreted as relatively rare specimens that were difficult to obtain. This would mean they were likely to have been traded at a supra-local level, but a concrete place of origin could not be established. Additionally, of the pieces from the Iron Age collection found in the gallery dolmen of the Palacio III megalithic complex, the prase quartz crystal (piece no.2) is an extraordinarily exotic specimen (even exceptional from a crystallographic perspective) and therefore, in all probability, would have been a highly prized and valuable object due to its rarity. Locations at Llerena or Malpartida de la Serena (Badajoz), or even certain mining areas in the south-east of Córdoba were suggested as potential places of origin for these items (Forteza González etal., 2008: 148–149; Murillo-Barroso etal., 2015a: 328–329).

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In view of the relative frequency with which quartz and rock crystal appear in southern Iberian (collective) funerary contexts of the 4th and 3rd millennia BCE, their disappearance from such contexts (both individual and collective), in the Early Bronze Age (from the beginning of the 2nd millennium BCE), is truly striking. It would seem that, between the end of the 3rd and the beginning of the 2nd millennia BCE the use of this raw material as grave goods was almost entirely abandoned.

This article is intended as a contribution into the research ofrock crystal use among the communities of Copper Age southern Iberia. The starting point for this study is a remarkable set of unpublished objects from the Chalcolithic site of Valencina de la Concepción (Seville). Among these are a dagger blade, 15arrowheads and a core found in two major megalithic monuments, plus other smaller items found in non-megalithic structures. Because of their size and technical characteristics, both the dagger blade and the core are unique specimens in thearchaeological record of Late Prehistoric Iberia. Their techno-morphological, geochemical and contextual analysis throws newlight on the use and social significance of rock crystal, asubject on which little research had been previously carried out.

Section snippets

Contexts

The settlement of Valencina de la Concepción-Castilleja de Guzmán (henceforth Valencina), is located in the lower Guadalquivir valley, within the metropolitan area of Seville. Valencina is one of the largest (around 450ha) and most significant sites for the study of Copper Age Iberia. In the last few years, various publications have given international dissemination to the research being carried out in this site, providing new ideas and valuable data related to key aspects of third millennium

Core and micro-blades

On a quantitative level, the presence of knapped rock crystal objects in southern Iberia Peninsula is better represented by small cores and micro-blades extracted by pressure knapping. Given its large size, the core deposited in the Montelirio tholos (Fig.5, Fig.6, Fig.7) is therefore an extraordinary find. The core, used for the extraction of small blades, is supported naturally by a hexagonal rock macrocrystal, four of whose faces are recognisable. The extractions were prepared through

Geochemical characterisation

Geochemical analysis through Raman has been carried out on three of the items: the core and one arrow head fragment from the Montelirio tholos and the dagger blade from PP4-Montelirio. Two are indicative of larger rock macrocrystals. Given that a larger set of objects was found in the Montelirio tholos, the same process has been applied to a arrow head found in this tomb in order to establish whether it could match the core found in the same tomb.

All three items analysed contain some evidence

Singularity of the technological process

Lithic technology achieved a high mark in the southern Iberian Copper Age (Nocete Calvo etal., 2005, Morgado etal., 2011, Morgado and Pelegrin, 2012). Specialisation is not only reflected in the exploitation of minerals carried out by certain communities with access to the region's best outcrops of siliceous rock (Ramos Millán etal., 1997, Linares Catela etal., 1998, Morgado and Lozano, 2011), but also by the development of complex production systems involving specific knapping methods and

Acknowledgements

We would like to thank Juan Manuel Vargas Jiménez and Ana Pajuelo Pando for the information they kindly provided regarding the excavated areas in IES, as well as García Lorca and Dinamarca streets. We also give our thanks to Ana Navarro Ortega, director of the Archaeological Museum of Seville, for enabling us to examine and photograph the pieces included in this study. This research was carried out within the research project “Study of the PP4-Montelirio Sector of Valencina de la Concepción,

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      High-pesticide-residue FV intake was unrelated whereas low-pesticide residue FV intake was inversely related to all-cause mortality, suggesting that exposure to pesticide residues through diet may offset the beneficial effect of FV intake on mortality.

    • Research article

      Microwear features on vein quartz, rock crystal and quartzite: A study combining Optical Light and Scanning Electron Microscopy

      Quaternary International, Volume 424, 2016, pp. 154-170

      In general, quartz and most of non-flint rocks have not been extensively studied from a functional point of view. Very frequently the definitions of micro-features connected with flint surfaces have been used to describe those encountered on non-flint tools. This circumstance has repeatedly posed serious methodological problems for evaluating the accuracy of functional results when analysing use-wear on quartz and quartzite implements. This is due to the intrinsic divergences in morphology and distribution of use-wear with regard to the different lithic raw materials.

      Even though important efforts to systematise use-wear features on quartz have been done almost since the beginning of the discipline, there continues to be confusion and lack of standardisation regarding terminology in this aspect.

      In this paper, we try to contribute to new insights in this research by means of selecting examples from an extensive experimental programme involving different raw materials: from rock crystal (the purest form of quartz found in nature) to vein quartz and quartzite, with the latter two materials extensively used for knapping throughout Prehistory and still poorly understood in terms of microwear. For data recording, we preferentially used sequential experiments and resorted to both Optical Light and Scanning Electron Microscopy.

      We focused our interest on describing the main groups of wear features. The results obtained allowed us to assess the different mechanical behaviours under the stressors induced by tool-use from a group of raw materials with the same chemical composition but very different in structure. Furthermore, we propose the revision of some terms commonly employed when documenting micro-wear on quartz and similar rocks, as well as recurring concepts coming from materials and geological sciences (e.g. tribology, quartz exoscopy...).

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