Distribution and chronological framework for Iberian variscite mining and consumption at Pico Centeno, Encinasola, Spain

Distribution and chronological framework for Iberian variscite mining and consumption at Pico Centeno, Encinasola, Spain Carlos P. Odriozola a, ⁎, Rodrigo Villalobos García b , Christopher I. Burbidge c , Rui Boaventura d , Ana C. Sousa d , Oliva Rodríguez-Ariza e , Rubén Parrilla-Giraldez a , M. Isabel Prudênçio c ,MaríaIsabelDias c a Department of Prehistory and Archaeology, University of Seville, María de Padilla S/N, 41004 Sevilla, Spain b Department of Prehistory, Archaeology, Social Anthropology and Historiographic Sciences and techniques, University of Valladolid, Pz/ del Campus S/N, 47011 Valladolid, Spain c Centre for Nuclear Science and Technology, IST, University of Lisbon, E.N. 10 ao km 139,7, 2695-066 Bobadela LRS, Portugal d Centre for Archaeology, University of Lisbon, Alameda da Universidade 1600-214 Lisboa, Portugal e Andalusian Centre for Ibearian Archaeology, University of Jaén, Paraje Las Lagunillas s/n, Jaén, Spain abstractarticle info Article history: Received 8 May 2015 Available online 8 January 2016 AMS radiocarbon and OSL dating, and profiling were used to directly delimit periods of variscite production at Pico Centeno Mine 2.These resultswere integrated with analysis of otherwell-dated periods of variscite production to establish an Iberian-wide chronological framework. Variscite production at Pico Centeno Mine 2 began at ~5200 BC, coincident with alpine jade production or Casa Montero Iberian flint production. Variscite was only used occasionally, together with other greenstones, during the 5th and 6th millennia BC. During the 4th millennium BC, variscite use began to increase to its apogee in the first half of 3rd millennium BC when it appeared in nearly every Iberian burial site. This increase in variscite production and use coincided with decline in the popularity of alpine jade. By the end of the 3rd millennium BC, new resources began to be valued such as Asian and African Ivory, Baltic and Sicilian amber, and copper-based metal products. The variscite cycle thus started with the decline of jade in the 5th–4th millennium BC, and ended with the appearance of copper, ivory and extra-peninsular amber by the end of the 3rd millennium BC. © 2015 University of Washington. Published by Elsevier Inc. All rights reserved. Keywords: Variscite Mining OSL 14C-AMS Iberia Pico Centeno Introduction Archaeological literature devoted to green body ornaments in Prehistoric Europe has thematically focused, almost exclusively, on the quest fortheoriginoftheseartefacts.Sincetheearly20thcentury,interpretations of the geographical origin of these ‘perles du calais’traversed continents, from Middle East turquoise mines to European variscite mines, initially pointing to a French origin at Montebras (Balagny, 1939), then later to the Pannacé aluminophosphate mines (Massé, 1971; Forestier et al., 1973a,1973b; Lheur, 1993), and finally to a Spanish origin at the Palazuelo de las Cuevas (Arribas et al., 1970, 1971)and Can Tintorer (Alonso et al., 1978; Bosch and Estrada, 1995; Villalba, 2002) variscite mines. Since the 1970s, research devoted to ‘calaite’beads has focussed on locating and characterising further new variscite sources. Source areas have been discovered at Bragança in Northeast Portugal (Meireles et al., 1987), at the Sarrabus deposit in Sardinia (Marini et al., 1989), at the variscite and turquoise outcrops of Punta Corveiro in Spain (Moro et al., 1995), and at the Pico Centeno variscite mines in Spain (Nocete and Linares, 1999;Fig. 1). This focus on identifying geological mineral sources has been driven by the view that their relationships to archaeological bead assemblages can be established by the intercomparison of their chemical compositions (Edo i Benaiges et al., 1995a; Dominguez Bella, 2004; Odriozola, 2014; Odriozola et al., 2010; Querré et al., 2014, 2008). To date, most papers devoted to beads continue to use calaite and variscite as synonyms. However, the increase in geochemical analyses of green mineral sources was paralleled by an increase in the numbers of analyses of ‘calaite’beads, and thus in the knowledge of the minerals used in beadmaking. Beads were found to include green mica, steatite, turquoise, talc and chlorite (Dominguez Bella, 2012). Therefore, calaite and variscite should not be considered synonyms, and the validity of the traditional analysis of variscite flows and consumption patterns (e.g., Dominguez Bella, 2012) is called into question. As the number of analysed beads increases, it becomes more apparent that Neolithic, Copper Age, and Bronze Age communities used nearly any available green mineral for beadmaking. The currentconsensus on the geographic focus of European variscite body ornament production points to Palazuelo de las Cuevas (Aliste, Zamora), Can Tintorer (Gavá, Barcelona) and Pico Centeno (Encinasola, Huelva; Dominguez Bella, 2004; Herbaut and Querré, 2004; Querré et al., 2008, 2014; Odriozola et al., 2010; Odriozola, 2014). The chronological span of variscite production is less clear, however. Arribas et al. Quaternary Research 85 (2016) 159–176 ⁎Corresponding author. Fax: +34 954559920. E-mail address: [email protected] (C.P. Odriozola). http://dx.doi.org/10.1016/j.yqres.2015.11.010 0033-5894/© 2015 University of Washington. Published by Elsevier Inc. All rights reserved. Contents lists available at ScienceDirect Quaternary Research journal homepage: www.elsevier.com/locate/yqres (1970, 1971) proposed that variscite production occurred during the Arabic period at Palazuelo de las Cuevas, based on the assumption that the city of Zamora was named after the Arabic word for emerald (zamarrad). Virgilio Sevillano (1978) and Campano Lorenzo et al. (1985) instead found that Roman pottery and prismatic blanks were associated with bead production at Las Cercas, and Copper Age variscite mining has been proposed at La Mazada (Sanz Mínguez, et al., 1990; Esparza Arroyo and Larrazabal Galarza, 2000). Both Las Cercas and La Mazada form part of the Palazuelo de las Cuevas complex. Meanwhile, Can Tintorer has been extensively dated to the Late Neolithic, between ~4500 and 3500 BC, based on burials, charcoals and seeds found in direct association with the mine galleries (Table 1). Jiménez Gómez (1995) attempted to chronologically order variscite production patterns at the Zambujal site (Torres Vedras, Central Portugal), based on radiocarbon ages and on mineralogical analysis. They concluded that production was mainly prehistoric; initially a mixture of greenstones was used, then variscite use dominated the second half of the 3rd millennium BC. Villalobos García (2012) has shown that this preference for variscite over other greenstones during the secondhalf of the 3rd millennium BC also occurred in the northern Spanish Meseta. Analyses of variscite exchange patterns have concentrated nearly exclusively on source and/or bead geochemistry (Alonso et al., 1978; Blasco et al., 1990; Dominguez Bella, 2004, 1996; Edo i Benaiges and Fernández Turiel, 1997; Edo i Benaiges et al., 1995a, 1995b;Edo i Benaiges et al., 1990; Fernández Turiel et al., 1996; Querré et al., 2008). Provenance analysis and consumption patterns often pinpoint a geological source that lacks not only evidence of production but also of any local human activity during periods relevant to the beads in question. No evaluation has been undertaken of the beads' archaeological relevance to the socioeconomic likelihood for exploitation of a source in a given locale duringa given period. In contrast to settlements, mines usually do not constitute wellstratified sites; instead, they constitute a complex system of use, reuse and re-location of products (Frumkin et al., 2014). Little, if any, datable material survives in direct stratigraphic association with the mined surface. In addition, mines usually experience several periods of production.Therefore, dating mining sites ischallengingand isusually based on: 1) time period-specific mine typology and/or mining technology (tool marks and debris); 2) artefacts typology; and 3) delimitation of production by dating materials found in spoil and/ or immediately pre-production contexts. Dating prehistoric mines based on typology and technology is therefore difficult. In Iberia, dating has resulted in chronological frameworks that span Late Prehistory without a clear delineation into different late prehistoric periods (Domergue, 1990; Hunt, 2003). The production chronology at Pico Centeno is controversial. Nocete and Linares (1999) identified three trench mines and Pérez Macías (2011, 2008) considered them to represent the Bronze Age and Roman copper exploitation. However, Pérez Macías (2008) argues that marks left on the extraction face by metal tools at Pico Centeno may represent soundings made in 1883 by the Mina de Cobre Santo Tomás (Jubes and Carbonell, 1920). Also, a Neolithic–Chalcolithic variscite production period has been proposed recently based on the Pico Centeno Mine 2 (PCM2) typology, the typo-technological marks on the surface of the mine, the typology of the mining tools, and indirectly by dating of contexts in which worked variscite beads, thought to originate from Pico Centeno, were found (Odriozola et al., 2010; Odriozola, 2014). Figure 1. Location of known Iberian variscite sources. 160 C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 Table 1 Available radiocarbon ages for European mining resources. Calibrated ages with 2 σuncertainty. Lab. code Site 14 age Uncertainty δ 13 C Calibrated age Mineral Reference yr BP +/−yr per mil yr BC Can Tintorer I-12730 4310 150 0 3365–2497 variscite Villalba et al. (1986) Can Tintorer I-12731 5350 190 0 4594–3713 variscite Villalba et al. (1986) Can Tintorer I-11786 5070 100 0 4142–3645 variscite Villalba et al. (1986) Can Tintorer UBAR-41 4970 100 0 3973–3534 variscite Villalba et al. (1986) Can Tintorer CSIC-488 4710 50 0 3634–3371 variscite Villalba et al. (1986) Can Tintorer CSIC-489 4940 50 0 3912–3639 variscite Villalba et al. (1986) Can Tintorer I-12158 4880 100 0 3943–3379 variscite Villalba et al. (1986) Can Tintorer UBAR-42 4820 100 0 3891–3366 variscite Villalba et al. (1986) Can Tintorer I-13099 4820 100 0 3701–3350 variscite Villalba et al. (1986) Can Tintorer UBAR-49 4740 90 0 3766–3091 variscite Villalba et al. (1986) Can Tintorer UBAR-30 4710 130 0 3658–3105 variscite Villalba et al. (1986) Can Tintorer UBAR-48 4690 100 0 3633–3036 variscite Villalba et al. (1986) Can Tintorer UBAR-47 4610 90 0 3365–2497 variscite Villalba et al. (1986) Can Tintorer I-12730 4310 150 0 3654–3039 variscite Villalba et al. (1986) Can Tintorer Beta-61491 4660 110 0 3943–3538 variscite Bosch and Estrada (1994) Can Tintorer Beta-72551 4930 70 0 3946–3662 variscite Bosch and Estrada (1994) Can Tintorer Beta-72552 5000 60 0 4038–3715 variscite Bosch and Estrada (1994) Can Tintorer Beta-72553 5100 60 0 4325–3791 variscite Bosch and Estrada (1994) S. Ferreres Beta-155686 5220 110 0 3943–3674 variscite Borrell et al. (2009) S. Ferreres Beta-250402 5000 40 0 3935–3657 variscite Borrell et al. (2009) S. Ferreres Beta-250403 4980 40 0 3935–3657 variscite Borrell et al. (2009) S. Ferreres Beta-250405 4980 40 0 3943–3704 variscite Borrell et al. (2009) S. Ferreres Beta-250406 5010 40 0 3943–3704 variscite Borrell et al. (2009) S. Ferreres Beta-250404 5010 40 0 5471–5322 variscite Borrell et al. (2009) Casa Montero Beta-206512 6410 40 −24.2 5324–5077 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-206513 6270 40 −26.2 5468–5229 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-232884 6360 40 −25.4 5358–5080 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-232885 6280 40 −24.9 5466–5225 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-232886 6350 40 −25.6 5367–5208 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-232887 6290 40 −22.2 5310–5066 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-232888 6240 40 0 5367–5208 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-232889 6290 40 −22.3 5533–5371 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-232890 6500 40 −25.6 5458–5215 silex Díaz del Rio and Consuegra Rodrígue (2011) Casa Montero Beta-232891 6320 40 −26.2 5324–5077 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-232892 6270 40 −26.2 5463–5217 silex Díaz del Rio and Consuegra Rodríguez (2011) Casa Montero Beta-232893 6330 40 −25.6 6009–5727 silex Díaz del Rio and Consuegra Rodríguez (2011) Defensola UTC-1342 6990 80 0 5887–5568 flint Díaz del Rio et al. (2008) Defensola Beta-71143 6820 80 0 4683–4362 flint Díaz del Rio et al. (2008) Defensola Beta-71144 5670 70 0 5666–5475 flint Díaz del Rio et al. (2008) Defensola Beta-80604 6630 70 0 5616–5376 flint Díaz del Rio et al. (2008) Defensola Beta-80603 6540 60 0 5626–5492 flint Díaz del Rio et al. (2008) Defensola UTC-1411 6630 40 0 5295–4860 flint Díaz del Rio et al. (2008) Tomaszów GrN-7594 6145 70 0 5300–4746 flint Díaz del Rio et al. (2008) Krzemionki Gd-1425 6090 110 0 4612–4367 flint Díaz del Rio et al. (2008) Porco AA-62119 5665 47 0 4829–4559 jadeite Petrequin et al. (2006) Porco AA-62120 5847 47 0 5212–4910 jadeite Petrequin et al. (2006) Porco AA-62121 6110 48 0 4960–4721 jadeite Petrequin et al. (2006) Porco AA-62123 5959 49 0 5218–4953 jadeite Petrequin et al. (2006) Porco AA-62122 6146 49 0 4934–4712 jadeite Petrequin et al. (2006) Porco AA-62125 5931 48 0 5309–5056 jadeite Petrequin et al. (2006) Porco AA-62124 6231 48 0 265–535 AD jadeite Petrequin et al. (2006) Bule AA-66511 1644 36 0 4340–4068 jadeite Petrequin et al. (2006) Bule AA-66512 5393 42 0 4517–4353 jadeite Petrequin et al. (2006) Bule AA-66513 5605 42 0 4517–4353 jadeite Petrequin et al. (2006) Bule AA-66514 5662 71 0 4682–4357 jadeite Petrequin et al. (2006) Bule AA-66515 6222 44 0 5303–5056 jadeite Petrequin et al. (2006) Bule AA-66516 5963 61 0 4996–4716 jadeite Petrequin et al. (2006) Bule AA-66517 6212 71 0 5323–4986 jadeite Petrequin et al. (2006) Cabrieres Beta-156929 3830 40 0 2458–2148 copper Ambert (2002) Cabrieres Beta-156928 3900 40 0 2480–2212 copper Ambert (2002) Araico Beta-312351 5640 40 0 4545–4367 Silex Tarriño et al. (2011) Araico Beta-312352 6050 40 0 5054–4838 Silex Tarriño et al. (2011) Tomaszów 6220 120 0 5467–4852 Silex Tarriño et al. (2011) Tomaszów 6145 70 0 5295–4860 Silex Tarriño et al. (2011) Tomaszów 5700 70 0 4707–4371 Silex Tarriño et al. (2011) Blackpatch BM-290 5090 130 0 4230–3643 silex Tarriño et al. (2011) Church Hill BM-181 5340 150 0 4460–3800 silex Whittle et al. (2011) Cissbury BM-183 4720 150 0 3892–3023 silex Whittle et al. (2011) Cissbury BM-184 4650 150 0 3700–2932 silex Whittle et al. (2011) Cissbury BM-185 4730 150 0 3907–3026 silex Whittle et al. (2011) Cissbury BM-3082 5100 60 −19.2 4038–3715 silex Whittle et al. (2011) Cissbury BM-3086 4710 60 −22.1 3634–3370 silex Whittle et al. (2011) Harrow Hill BM-182 4930 150 0 4040–3370 silex Whittle et al. (2011) (continued on next page) 161C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 The dating of variscite mines is a crucial step to evaluate variscite production, consumption, and its socio-cultural significance. As such, our paper focuses on directly dating the exploitation of PCM2 by means of the combined luminescence and radiocarbon dating of three features. One of the features is an extraction face in which we found charcoal in the base level. This may relate to the setting of fire against a rock face to weaken it and so facilitate mining. The second feature is a pit that we suggest corresponds to a later phase of mining activity, and the third consists of tailings located adjacent to the face and pit. We also use indirect dating of PCM2 through the analysis of well-dated contexts containing variscite artefacts. Both the direct and indirect chronological datasets will be at the centre of a debate focussed on the production of a tentative model for Iberian variscite production and consumption. PCM2 direct dating The outcrop of the PicoCentenoaluminophosphate deposit includes threeopencast trenchmines.Thetypologyofthemines resemblesthose of prehistoric mining activity (Shepherd, 1980; Domergue, 1990; Craddock, 1995; Hunt, 1996, 2003). We performed an excavation in PCM2, where we conducted 5 test cuts (A-to-D) in 2011 (Fig. 2). In addition to early extraction activity, indicated by small cavities following variscite veins, and tool-marking scars created by mallets and hammerstones, we also detected an excavation made by metallic picks that could date from Roman times to the 20th century ‘copper fever’(Pérez Macías, 2008, after Jubes and Carbonell, 1920). In summary, prehistoric features at PCM2 include an accessramp cut into the rock, a central transit area, and an extraction face with small cavities. These are characterised by concave marks left by the impact of rounded-edged tools (Odriozola and Villalobos García, 2015;and see Craddock, 1995, for a detailed summary of the mining technology). A 2 m deep pit near the access area suggests additional non-prehistoric production, which cut the prehistoric facies, and has marks left on the extraction face by metal tools. In addition to the possibility that PCM2 was mined in recent times, the mining tools found during excavations, including quartzite cobbles, chisels and picks, point to prehistoric use. This most likely relates to an early stage of variscite exploitation during Late Prehistory. Stratigraphy Pico Centeno, similar to many other mines in Iberia, exhibits a long history of use, re-use, and re-location of products and debris, which results in a complex stratigraphy (Fig. 3). Table 1 (continued) Lab. code Site 14 age Uncertainty δ 13 C Calibrated age Mineral Reference yr BP +/−yr per mil yr BC Harrow Hill BM-2099R 5040 120 −23.1 4225–3536 silex Whittle et al. (2011) Harrow Hill BM-2097R 5140 150 −25.2 4319–3651 silex Whittle et al. (2011) Harrow Hill BM-2071R 4900 120 −26.7 3960–3377 silex Whittle et al. (2011) Harrow Hill BM-2075R 5020 110 −26.4 4044–3539 silex Whittle et al. (2011) Harrow Hill BM-2124R 5060 90 −24.9 4037–3657 silex Whittle et al. (2011) Harrow Hill BM-2098R 5350 150 −25.7 4486–3802 silex Whittle et al. (2011) Harrow Hill BM-3084 4880 30 −21.9 3706–3638 silex Whittle et al. (2011) Harrow Hill BM-3085 5070 50 −23.4 3970–3715 silex Whittle et al. (2011) Long Down OxA-1152 5050 100 0 4041–3647 silex Whittle et al. (2011) Spiennes Lv-1566 5510 55 0 4458–4259 silex Collet (2004), Collet et al. (2008) Spiennes GrN-4674 5420 75 0 4444–4046 silex Collet (2004), Collet et al. (2008) Spiennes Lv-1598 5100 65 0 4039–3713 silex Collet (2004),Collet et al. (2008) Spiennes KN-I.16 5110 40 0 3980–3797 silex Collet (2004),Collet et al. (2008) Spiennes OxA-3196 4830 80 0 3778–3376 silex Collet (2004),Collet et al. (2008) Spiennes Beta-194770 4580 40 0 3499–3105 silex Collet (2004),Collet et al. (2008) Spiennes Beta-194771 4550 40 0 3484–3100 silex Collet (2004),Collet et al. (2008) Spiennes Beta-110683 4500 50 0 3361–3027 silex Collet (2004),Collet et al. (2008) El Milagro (Asturias) OxA-3005 3990 90 0 2865–2210 copper Collet (2004), Collet et al. (2008) El Milagro (Asturias) OxA-3006 3850 90 0 2567–2036 copper de Blas Cortina (2011) El Milagro (Asturias) Ua-33207 3785 35 0 2338–2051 copper de Blas Cortina (2011) El Milagro (Asturias) Ua-33209 3775 35 0 2331–2043 copper de Blas Cortina (2011) El Milagro (Asturias) Ua-24538 3630 40 0 2133–1892 copper de Blas Cortina (2011) El Milagro (Asturias) Ua-24537 3520 40 0 1950–1704 copper de Blas Cortina (2011) El Milagro (Asturias) Ua-24550 3355 45 0 1747–1527 copper de Blas Cortina (2011) El Milagro (Asturias) Ua-33206 3285 35 0 1643–1460 copper de Blas Cortina (2011) La Profunda (León) Ua-35778 3865 35 0 2464–2209 copper de Blas Cortina (2011) La Profunda (León) Ua-35779 3950 35 0 2570–2310 copper de Blas Cortina (2011) La Profunda (León) Ua-35780 4075 35 0 2858–2490 copper de Blas Cortina (2011) El Aramo (Asturias) OxA-1833 4090 70 0 2872–2488 copper de Blas Cortina (2011) El Aramo (Asturias) OxA-1926 3810 70 0 2466–2040 copper de Blas Cortina (2011) El Aramo (Asturias) OxA-3007 3900 90 0 2623–2057 copper de Blas Cortina (2011) El Aramo (Asturias) OxA-6789 3995 50 0 2833–2345 copper de Blas Cortina (2011) El Aramo (Asturias) Ua-18629 3775 65 −21.4 2456–2028 copper de Blas Cortina (2011) El Aramo (Asturias) Ua-18630 3365 60 −20.1 1872–1504 copper de Blas Cortina (2011) El Aramo (Asturias) Ua-18631 3310 65 −20.4 1743–1446 copper de Blas Cortina (2011) El Aramo (Asturias) Ua-18632 3825 60 −20.5 2467–2062 copper de Blas Cortina (2011) El Aramo (Asturias) Ua-18633 3940 60 −20.1 2580–2210 copper de Blas Cortina (2011) El Aramo (Asturias) Ua-18634 3215 55 −22 1623–1327 copper de Blas Cortina (2011) Chiflón BM-1600 4840 50 0 3756–3389 copper Acosta (1995) Chiflón BM-1599 4780 50 0 3654–3378 copper Acosta (1995), Castro Martínez et al. (1996) Chiflón OxTL-200e3(II) 4000 300 0 3353–1744 copper Acosta (1995) Rio Tinto BM-2337R 2650 140 0 1121–406 copper Castro Martínez et al. (1996) Chiflón BM-1529 3320 130 0 1939–1297 copper Burleigh et al. (1982), Rothenberg and Frejeiro (1980) Chiflón BM-1528 2650 60 0 972–590 copper Burleigh et al. (1982), Rothenberg and Frejeiro (1980) Chiflón BM-1601 2520 210 1190–108 copper Burleigh et al. (1982),Rothenberg and Frejeiro (1980) 162 C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 In cut B at PCM2 (Fig. 3), horizontal sedimentary units were identified through the stratigraphy. These are interpreted as floor units that are associated with the mining activities and movement of materials to the exterior of the mine. A deep excavated pit was recorded to cut these floor units (cut B, Fig. 3). The last floor unit (test cut A SU 9, test cut B SU 11 and test cut C SU 12/13) used before the abandonment of the mine contained numerous stone tools such as picks and wedges that show strong use wear, small production debris with concave marks, and charcoal remains that adhere to both the extraction faces and the floor. We argue that the Figure 2. Test cut position and 3D model. Pico Centeno's PCM2 extraction face location is 38.161534738°N/6.949741517°W (WGS84, EPSG: 4326). Figure 3. A) PCM2 planimetry and cuts A, B and C North profiles and cut B East profile stratigraphies; B) Harris matrix of cut B (software matrix Harris composer). 163C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 abundance of charcoal in the base level and on the surface indicates the use of fire-setting technology (Willies, 1994; Craddock, 1995; Weisgerber and Willies, 2000). The floor units were sealed by apparently rapid accumulations of large and medium size rock blocks, which indicates human infilling with debris. The rubble was sealed by several apparently slower, natural, accumulation units, which were in turn sealed by a recent compact ground surface layer that is similar to the floor units mentioned above. A pit that cuts all units from the approximate actual surface level wasencountered in test cut B.Thebase of this pit contained severalhorizontal fill units (SU 21-to-24) indicative of gradual infill by slopewash after abandonment. The mid sequence contained a series of oblique stony units that may indicate an episode of intentional human infill [SU 16–20], and this infill were capped by several relatively finegrained sub-horizontal units indicative of gradual (natural) deposition [SU 13–15] (Figs. 3 and 4). Luminescence dating In this study, two complementary approaches to luminescence dating analysis were used. Semi-quantitative luminescence profiling combines simple sample preparation with multi-signal measurement: infrared- (IRSL), optically- (OSL) and thermally- (TSL) stimulated luminescence, of numerous small samples from around a site. This enables evaluation of dominant luminescence signals to guide subsequent sample preparation and fully quantitative analysis;it providesindicationsof whether material has been heated or not, and efficiently produces semiquantitative estimates of absorbed dose with elevated stratigraphic resolution (Sanderson et al., 2001; Burbidge et al., 2007; Rodrigues et al., 2013; Odriozola et al., 2014). Thirteen profiling samples were taken using stainless steel tubes 2 cm diameter and 5 cm long from the cut B section (Figs. 2 and 4), plus two from the base of cut C (Figs. 2 and 3). The unexcavated volume of material remaining in cut C was too small for a quantitative dating tube: quantitative dating analyses ofalessernumberoflargersamplesweremadeusingOSL.Thesecomprised three tubes, 3.8 cm in diameter and 15 cm long, of sediment and a piece of rock from cut B (units 6, 11, 13 & 18 in Fig. 4;Table 2), plus a tube of sediment from cut D (ITNLUM 701). Theeast section of test cut B waschosen for OSL dating and profiling because it was the deepest available stratigraphic section at the site (Fig. 4) and was initially expected to include both prehistoric facies and the more modern pit fills. Samples for quantitative OSL dating were taken from the least stony layers (Table 2). In addition, one rock was collected to test whether the tailings included material to which fire had been set to facilitate mining. The remaining stratigraphic units were sampled for semi-quantitative luminescence profiling to test the severity of the residual signals in the stonier layers and/or to help delimit the phases of accumulation. The two additional profiling tubes were extracted from the remaining regolith at the base of cut C, close to the 14 C sample locations, to test the chronological relations between the cuts and between the OSL and 14 C dating results. The sample taken for quantitative analysis from the south section of cut D (ITNLUM 701) was designed to help evaluate the chronological relation between the fills in cut B and the layers of tailings spread around the mine site. Luminescence and dosimetric measurements In luminescence dating, the dose of ionising radiation absorbed by a crystal (absorbed dose, measured in Gy) since a heating or light exposure event of sufficient severity, is evaluated by comparing TSL or OSL signal from the as-prepared sample with those from laboratory irradiations (Burbidge, 2012, 2015). Comparison of doses from TSL and OSL can thus indicate whether a sample was heated or exposed to light. Assuming that the absorbed dose resulted from long-lived radionuclides in a fixed geometry, the dose rate (measured in Gy/ka) may be calculated fromparentradionuclide concentrationsof the sample or in situ dose rate measurements. Luminescence measurements were made on 3 Risø DA-15 and DA-20 readers using integrated 90 Sr/ 90 Y irradiators calibrated relative to the primary 60 Co standard of LPSR and CTNmetrology laboratory (Reader 1, 75 ± 4 mGy/sβ;Reader2,95±3mGy/sβ;Reader3, 111 ± 3 mGy/sβ). Figure 3 (continued). 164 C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 For semi-quantitative luminescence profiling (Sanderson et al., 2001), a basic series of preparatory treatments was used to separate coarse (90–250 μm) 40% HF etched fractions enriched in quartz; they were measured using a simple multi-stimulation protocol (Rodrigues et al., 2013; Odriozola et al., 2014). The profiling approaches referred to above have calibrated signals from the as-prepared material on an aliquot-to-aliquot basis, using signals that resulted from a single regenerative dose in the quasi-linear region of the sample's dose response. In the present case, the as-prepared signals from the profiling samples varied strongly and were often much greater than those produced by the calibration dose (e.g. Burbidge et al., 2007). The extrapolation of the quasi-linear calibration dose response would tend to overestimate the signal that resulted from doses in the range of 10–200 Gy, in which the effects of saturation in the dose response, particularly from quartz, would be expected to be evident. To help explain the signal saturation and to permit comparison between all results, the absorbed doses of the profiling samples were estimated by using a common saturating exponential dose response characteristic (DRC). This was obtained directly from the profiling measurements. It was defined by using the average of the standardised (Roberts and Duller, 2004) postIR OSL responses to 50 sβ, with test dose of 10 sβused in all analyses (Burbidge et al., 2006), all measured on Reader 3. The DRC is described by a single saturating exponential function, I=I ∞ (1 −exp(−D/D) using a signal at saturation (I ∞ ) equal to the average dose of signal saturation (D)(Burbidge, 2015), which was found to be 40 Gy. SemiFigure 4. A) Cut B East profile stratigraphy and B) cut D North profile stratigraphy, with the detailed quantitative OSL sample position (big dots) and semi-quantitative OSL profiling (small dots). Table 2 Brief description of the units sampled for OSL dating. Sample # Cut Unit Description ITNLUM 696 B 6 A bonfire nearby the extraction surface ITNLUM 697 B 10 Rock sample. This unit seems to be directly related with the last episode of prehistoric exploitation. This unit accounts for the 15% of the stone tools recovered. Units are cut by the pit. ITNLUM 698 B 13 It is interpreted as a modern depositional unit filling the pit. ITNLUM 699 B 18 Take part of the oblique depositional units that fills the pit with big rock blocks. ITNLUM 701 D 6 Depositional unit, believed to be part of production debris accumulation. 165C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 quantitative age values were estimated by interpolating the total dose rates calculated for the quantitative dating samples. In this study, sampling and analysis for quantitative luminescence dating were undertaken using the methods of Burbidge et al. (2014), which are based on a combination of instrumental neutron activation analysis (INAA, Dias et al., 2013; Dias and Prudêncio, 2007; Gouveia and Prudêncio, 2000; Prudêncio et al., 2006), high resolution gamma spectrometry (HRGS, Trindade et al., 2013), field gamma spectrometry (FGS; Trindade et al., 2014), water absorption and retention under free drainage, and OSL measurements. In the present case FGS was conducted using both Target Nanospec and HPI Rainbow Multi Channel Analysers, each with 2″×2″NaI probes. Water content was measured as a fraction of dry sample mass (50°C) with the sample in its as-received or ‘field’state, once saturated, and following free drainage for 1 h, and 1, 2, 4 and 8 days (W f ,W s ,W D0–8 ; Burbidge et al., 2014). One end of each sediment sample tube was sealed with tape and the other end was closed with nylon mesh; the rock was brushed clean of loose material and weighted (W f ). Inverted tubes and the rock were soaked overnight in deionised water and weighed after removal of standing water (Ws). Tubes were then unsealed and set to drain on an inclined board; the rock was drained on an inclined sieve (W D0–8 ). Fills that were rich in weathered pelitic host rock were highly water retentive; the clast-rich mine-waste and the sample of rock drained more completely. Differences between K and Th concentrations estimated by FGS, HRGS and INAA (Tables 3a and 3b) were explainable using attenuation by W f for the more deeply buried samples. Representative drained values were used for samples from superficial, i.e., drier layers (ITNLUM 696, 701). Sampling was conducted in late autumn, in days following rain: well-drained ground had not been subject to prolonged wetting and was expected to retain a slightly greater than minimum water content, whereas samples from the poorly drained pit had been subject to prolonged wetting and were expected to retain greater than average water contents. On this basis the time averaged burial values for the fill and rock samples (ITNLUM 696-9) were estimated as the average of W f for each sample and that of the driest sample (ITNLUM 701); the upper value in the average calculation for ITNLUM 701 was chosen as W D8 . The mineralisation associated with the precipitation of aluminophosphates to produce variscite at PCM2 apparently also resulted in the presence of moderately elevated levels of U (Tables 3a and 3b). Therefore, to test for disequilibrium in the upper U-series, HRGS was performed for each quantitative dating analysis. 23–31 g of milled material was sealed and equilibrated in polystyrene Petri dishes. Twenty five emission lines from 40 K and the 235 U, 238 Uand 232 Th decay series were mass-normalised and compared with the reference samples GSS1, GSS5,GSR6usedforINAA.Significant disequilibrium in the upper series was not apparent, and the weighted mean results over all emissions yielded similar results to the INAA (Tables 3a and 3b). However, after accounting for in situ water content, U dose rates obtained from (unsealed) FGS measurements were 10%–30% lower than INAA (parent 238 U) or the weighted mean HRGS (sealed). Given the relatively wet conditions in the pit at the time of sampling, the low FGS results are considered to indicate minimum 222 Rn loss in the field. Since this appeared to better approximate burial conditions in the fills and mine wastes, the FGS U values were chosen for age calculations for samples ITNLUM 696, 697, 699 and 701. The cosmic dose rate was estimated by averaging values calculated based on as-sampled burial depth and the height of the adjacent rock. Calculations were based on Prescott and Stephan (1982) and a fitto the data of Prescott and Hutton (1988). With respect to the OSL analyses per se, the pelitic host rock produced abundant fine silica, the agglomerates of which exhibited slow OSL signal decay, poor recycling and strong recuperation in the single aliquot regenerative (SAR) OSL protocol (Murray and Wintle, 2000). Relatively small quantities of 90–160 μm size quartz were obtained for quantitative OSL analyses: this required repeated disaggregation, sieving, cleaning with HCl, density separation, HF dissolution (40%, 40 min), and re-sieving. In the analyses ITNLUM 696, 697, 699, 701, thecalibration curve usedthefollowingradiation exposures:0 (As-prepared), 20, 0, 5, 10, 40, 80, 0, 20, 20 (IR) sβ;testdoseD T =10sβ(the reader used to measure each sample is listed in Tables 3a and 3b), and the results were fitted with a single saturating exponential. Initial tests indicated that the quartz grains from sample PCM3 yielded relatively low OSL signals but high absorbed dose values. Thus, in the analysis ITNLUM 698 the calibration curve used exposures of: 0 (As-prepared), 200, 0, 800, 1600, 3200, 6400, 0, 200, 200 (IR) sβ;D T =50sβ,andthe results were fitted with a saturating exponential plus linear function. Inallcases,preheatsweremadeat180,200,220,240,260and280°C/ 30 s to test for differences in the absorbed dose estimates as a function of the relative filling of, and/or transfer of the charges between, electron and hole traps during calibration and test irradiations and OSL measurements. All measurements that used the 180 and 280°C/30 s preheats were rejected in the analyses of ITNLUM 696, 697, 699 and 701, since systematic deviations or increased scatter in absorbed dose values were commonly observed. For ITNLUM 698, scatter in the absorbed dose estimates was great for all preheats, and the test-normalised OSL signal from the as-prepared material did not intercept the calibration curve in two cases (Tables 3a and 3b). For the accepted measurements in each analysis, the average recycling ratios ranged from 0.93 to 1.01, and from 0.96 to 1.00 (0.81, ITNLUM 698) after exposure to infrared light. The average zero dose responses were b6% of the average absorbed doses.The OSL signal per unit dose wasrelatively low for samples from the pit (Tables 3a and 3b), and for ITNLUM 698 it declined by 50% during the measurement sequence. Signal integrals that used the majority of the initial OSL decay as signal, with ‘late’background subtraction, were therefore applied for dating calculations in all cases. Use of the initial signal gradient, i.e., counts in the third and fourth channels subtracted from those in the first two channels measured during OSL, resulted in highly dispersed datasets. The weighted mean (1/variance) appeared consistent with the main grouping of accepted absorbed dose measurements in the analyses of ITNLUM 696, 697, 699, and 701, and was used to calculate central absorbed dose estimates for use in age calculation. However, individual Table 3a Luminescence dating measurements: radionuclide concentrations and estimates of water content. PCMII ITNLUM Sample type a Depth b FGS in situ c H 2 O in situ HRGS lab,dry INAA lab,dry H 2 O K Th U Ref. K Th U K Th U Time averaged (cm) (%) (ppm) (g/g) A10/ (%) (ppm) (%) (ppm) (g/g) 1 696 T 30 1.5 9.1 7.6 0.37 256 2.4 13 16 2.2 12 14 0.10 2 697 T 53 1.7 9.6 7.9 0.36 257 2.3 14 15 2.3 12 14 0.19 3 698 R 86 1.5 8.7 7.6 0.37 258 1.8 11 13 1.9 11 11 0.19 4 699 T 132 1.8 7.3 14 0.38 259 2.6 14 23 2.6 12 23 0.20 5 701 T 47 1.7 11 8.1 0.08 260 1.8 12 14 1.7 12 13 0.09 Average uncertainty 0.1 1.2 1.1 0.02 0.1 1.8 0.6 0.2 0.7 0.4 0.15 a Tube; rock. b Below pre-excavation ground level. c As measured, i.e. not corrected for in situ water content. 166 C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 absorbeddosesmeasuredbyOSL fromtherock(ITNLUM698)exhibited scatter to very high values, so that the weighted mean for this sample is considered merely to indicate a minimum estimate. These OSL results, and comparison of OSL and TSL in test measurements indicate that the rock was not heated: finite OSL measurements are thought to have been due to the aforementioned poor behaviour within the SAR protocol. For age estimation, the different measurements were combined in accordance with the approach outlined in Burbidge et al. (2014). Alpha, beta and gamma dose rates from the environment that surrounded the sample location were estimated from FGS measurements, after correcting for measurement geometry and the difference between the in situ and the time averaged water contents. The attenuated environmental dose rates were combined with the self-dose rate of a volume of representative size and density for the adjunct samples taken from the holes excavated for FGS measurement. This was based on the dimensions of the holes, radionuclide concentrations from INAA and HRGS (U from FGS) on material from the adjunct sample, and the time-averaged water contents estimated from measurements on the tube samples. The attenuated dose rates from the environment and the adjunct were then combined with similarly estimated values for the samples themselves; for the tube samples the water content and radionuclide concentrations were assumed equal to the adjunct. The dose rates to the etched cores of the quartz grains measured by OSL were calculated from these values, and all were combined with calculated cosmic dose rates to estimate the total dose rates for the grains measured by luminescence. For each sample, the weighted mean OSL absorbed dose estimate from the grains was divided by the dose rate to estimate the age, which was converted an estimate the calendar age. AMS-radiocarbon dating Radiocarbon measurements were performed using a 1 MV accelerator mass spectrometer (AMS) at the facilities of the University of Sevilla (Centro Nacional de Aceleradores) on 5 charcoal samples recovered at the base level of test cut C (unit 12/13). The chemical preparation of the samples followed standard procedures (Santos Arevalo et al., 2009). A Soxhlet extraction was applied using hexane, acetone and ethanol before treating the samples with theAcid–Alkali–Acid cleaning procedure (AAA). For the AAA procedure, 0.5 M HCl and 0.1 M NaOH were used, and time wascarefully controlled to avoid severe losses by dissolution. Between 7–10 mg of clean and dry charcoal wascombusted at 950°C for 3 h in a vacuum-sealed quartz tube with CuO and Ag powder. The quartz tubes had been previously baked at 950°C to eliminate possible organic matter. The CO 2 produced was then reduced to graphite by adding excess H 2 and using cobalt as a catalyst. The resultant mixture of graphite and cobalt was pressed into aluminium cathodes and retained in a vacuum until measurement (Santos Arevalo et al., 2009). The PCM2 site had little organic material suitable for radiocarbon dating: no materials from short-lived organisms materials were recovered from the excavations, and the only charcoal of sufficient size were obtained from cut C level 12/13. AMS radiocarbon ages are reported in conventional radiocarbon years (Stuiver and Polach, 1977) and calibrated using Calib 7.1 with Intcal'13 (Reimer et al., 2013)incal.BC(2σuncertainty) and as BP (Table 4). Anthracological analysis was performed on the charcoal fragments after removal of the samples for AMS-radiocarbon dating. The small size and poor preservation of the charcoal samples limited the anthracological determinations to angiosperm, and in some cases the proposal of a taxon (Table 4). Indirect dating Ideally, evidence should be combined from the excavations of several well-dated sites that contained beads, pendants or charm-assemblages made from variscite. Unfortunately, accurate identification of bead mineralogy is lacking for most ‘green bead’contexts in Iberia, where many green minerals other than variscite were used for beadmaking. To realistically produce a chronological framework for variscite consumption we need first to identify bead mineralogy. The mineralogical classification of beads by means of portable analytical devices is not straightforward and deserves a full-length paper of its own. However, we have developed a simplified approach for the purpose of helping to evaluate bead chronologies. This methodology includes mineralogical identification of beads (1392 samples from 42 different sites along the Iberian Meseta and Atlantic Façade) based on the chemical composition using an OxfordInstrument XMET-7500 portable X-rayspectrometer with a Rh tube, a silicon drift detector (SDD),and an automatic 5-position filter changer. The identification of aluminophosphate is relatively straightforward based on Al-to-P atomic ratios.X-ray diffraction has confirmed variscite as the main crystallographic phase in almost all samples, either geological or bead-worked, with an Al-to-P atomic ratio in the compositional range of variscite [[MPO 4 ·2H 2 O], where M = Al 3+ ,Fe 3+ ,Cr 3+ ,V 3+ (Larsen, 1942)], from ~1 to 1.8 (refer to Odriozola et al., 2010,and Odriozola, 2014). Thus, here we use the Al-to-P atomic ratio as an indicator of variscite as the raw material of beads. Nevertheless, turquoise, crandalliteor aheylitemay occurseparatelyorasminorcrystallographic phases together with the variscite (Larsen, 1942). In these cases, the Al-to-P atomic ratios need to be combined with Ca, Cu and Fe values to differentiate between minerals. Differentiating green stones formed by sheet silicates, e.g., micas, talc-steatite, chlorite and serpentine, is more complicated. We conservatively classified beads as aluminophosphate, K-aluminosilicates, Mg-aluminosilicates, Mg-silicates or other silicates, based on their major element composition obtained by XRF: dominant P + Al = aluminophosphate; dominant K + Al + Si = K-aluminosilicate; Table 3b Luminescence dating measurements: summary dose rate, absorbed dose, and calendar date estimates. PCMII ITNLUM Sample Type a Depth b Dose rate OSL Absorbed dose Calendar age Ḋ Cosmic σ Ḋ Ḋ total σ Ḋ Reader Aliquots Ī T1d Dσ D (cm) (mGy a −1 ) (mGy a −1 )=/b/N/? c /24 (cts) (Gy 60 Co) =/b/N/? c Date σ age 1 696 T 30 0.14 0.04 5.60 0.29 = 2 16 420 0.63 0.09 = 1900 20 AD 2 697 T 53 0.13 0.04 5.25 0.38 = 2 16 215 0.73 0.09 = 1870 20 AD 3 698 R 86 0.12 0.03 4.79 0.31 = 1 22 186 55 11 ? 9000 2000 BC 4 699 T 132 0.12 0.03 6.97 0.59 = 3 16 362 1.34 0.19 N1820 30 AD 5 701 T 47 0.22 0.01 4.79 0.27 = 3 16 2380 1.08 0.12 N1790 30 AD a Tube; rock. b Below pre-excavation ground level. c Summary assessment of dosimetry and luminescence results. =/b/N: equal to/overestimates/underestimates “true”value, within quoted uncertainties. ?: potentially without uncertainties. d Signal intensity measured in response to the first test dose in the SAR measurement sequence, averaged over all aliquots. 167C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 1975; Gonçalves and Reis, 1982; Blasco et al., 1997; Bueno Ramírez et al., 2005; Costa et al., 2011; Villalobos García, 2012). Therefore, the use of variscite beads became extremely popular; achieving a period of maximum spread and use during the first half of the 3rd millennium BC, whereas the use of other green stones became rare (Fig. 7 and Table 5). From ~2500 BC onwards variscite use began to decline, but not in favour of other greenstones, the use of which had already declined in favour of variscite (Villalobos García, 2012). Rather, this coincides with increased availability of copper-based metals (Murillo-Barroso and Montero Ruiz, 2012), and new ‘exotic’resources such as Asian and African Ivory (Schuhmacher et al., 2009; Schuhmacher, 2012), and Baltic and Sicilian amber (Murillo-Barroso and Martinón-Torres, 2012). Conclusions AMS radiocarbon and OSL dating of PCM2 indicate a long history of use, from the end of the 6th millennium BC Neolithic exploitation of variscite to the 19th century AD copper soundings made by Mina de Cobre Santo Tomás. The OSL dating indicates that fills and tailings accumulated in their present positions in the late 18th and late 19th centuries.The AMS radiocarbon datingof apparently in situ material set atthe rear of the mine excavation indicated a palimpsest from the Neolithic, Iron Age and Mediaeval periods. The semi-quantitative OSL profiling results, from small samples obtained from stony layers and the remnants of excavated fills that were not amenable to sampling for fully quantitative OSL analysis, corroborate the chronological indications from both quantitative OSL and from AMS-radiocarbon. Thus, radiocarbon and OSL dating provide complementary information on different phases of site usage, which is linked by luminescence profiling. Our new datasets support an interpretation of intermittent low intensity mining activity over a prolonged period. The intensity appears similar to that of 3rd millennium BC North Iberian copper mining, which has been calculated as 35 person-days of labour over 800 years (de Blas Cortina, 1998). The present dataset locates the beginning of variscite consumption coeval in time to the decline of jade in the 5th–4th millennium BC; the end coincides with the appearance of other signifying items in the second half of the 3rd millennium BC such as copper, ivory and extra-peninsular amber. Variscite consumption achieves its apogee in ~3000 BC, when it appears in nearly every Iberian burial (Jiménez Goméz, 1995; Villalobos García, 2012). Acknowledgments The authors acknowledge the Ministerio de Economía y Competitividad (HAR2012-34620)for their financialsupport.Odriozola acknowledges Universidad de Sevilla for a postdoctoral grant. Burbidge acknowledges PTDC/AAC-AMB/121375/2010 for implementation of gamma spectrometry. Appendix A. Supplementary data Supplementary data to this article can be found online at http://dx. doi.org/10.1016/j.yqres.2015.11.010. References Acosta, P., 1995. Las culturas del neolítico y calcolítico en Andalucía Occidental. Espacio Tiempo y Forma. Serie Prehistoria y Arqueología 8, 33–80. http://dx.doi.org/10. 5944/etf+i.8.1995.4720. Alonso, M., Edo, M., Gordo, L., Villalba, M.J., 1978. Explotación minera neolítica en Can Tintorer. Pirenae 13–14, 7–14. Ambert, P., 2002. Utilisation préhistorique de la technique minière d'abattage au feu dans le district cuprifère de Cabrières (Hérault). Comptes Rendus Palevol 1, 711–716. http://dx.doi.org/10.1016/S1631-0683(02)00078-7. Arribas, A., Nicolau, J., Burg, R., 1970. A new ocurrence of variscite in Spain. Lapidary Journal 107, 764. Arribas, A., Galán, E., Martín-Pozas, J.M., Nicolau, J., Salvador, P., 1971. Estudio mineralógico de la variscita de Palazuelo de las Cuevas, Zamora (España). Studia Geologica Salmanticensia 2, 115–132. Balagny, C., 1939. Le mystere de la callais. Societé Archéologique de Nantes 79, 173–216. Baldellou, V., Utrilla Miranda, P., García-Gazólaz, J., 2012. Variscita de Can Tintorer en el Neolítico Antiguo del Valle Medio del Ebro. In: Borrell, M., Borrell, F., Bosch, J., Clop, X., Molist, M. (Eds.), Actes Xarxes al Neolític. Museu de Gavà, Gavà (Barcelona), pp. 307–314. Blasco, A., Edo i Benaiges, M., Villalba, M.J., 1990. Les perles en callaïs du sud de la France proviennent-elles des mines de Can Tintorer? Archéologie en Languedoc Congrès Hommage au Dr Jean Arnal.Colloque international (20/09/1990), pp. 279–289 Blasco, A., Villalba, M.J., Edo i Benaiges, M., 1992. Cronologia del complex miner de Can Tintorer. Aportacions a la periodització del Neolític Mitjà Cátala. Estat de La Investigació Sobre El Neolític a Catalunya. 9è Col · loqui International d'Arqueologia de Puigcerdà. Ajuntament de Puigcerdà, Puigcerdà, pp. 215–219. Blasco, A., Villalba, M.J., Edo i Benaiges, M., 1997. Aspectos sociales del Neolítico Medio catalán. In: Balbín Behrmann, R., Bueno Ramírez, P. (Eds.), II Congreso de Arqueología Peninsular. Neolítico, Calcolítico y Bronce. Fundación Rei Afonso Henriques, Zamora, pp. 89–98. Boaventura, R., 2011. Chronology of Megalithism in South-Central Portugal. In: García Sanjuán, L., Scarre, C., Wheatley, D. (Eds.), Exploring Time and Matter in Prehistoric Monuments: Absolute Chronology and Rare Rocks in European Megaliths. Junta de Andalucía, Sevilla, pp. 159–192. Borrell, F., Bosch, J., Vicente, O., 2009. Datacions per radiocarboni a les mines neolítiques de la serra de les Ferreres de Gavà. In: Bosch, J., Borrell, F. (Eds.), Intervencions arqueològiques a les Mines de Gavà (sector serra de les Ferreres). Anys 1998–2009. Museu de Gavà, Gavà (Barcelona), pp. 241–246. Bosch, J., Estrada, A., 1994. El neolític postcardial a les mines prehistòriques de Gavà (Baix Llobregat). Museu de Gavà, Gavà (Barcelona). Bosch, J., Estrada, A., 1995. La mineria en Gavá (Bajo Llobregat) durante el IV milenio AC. Rubricatum 1, 265–270. Bueno Ramírez, P., Barroso Bermejo, R., de Balbín Behrmann, R., 2005. Ritual campaniforme, ritual colectivo: la necrópolis de cuevas artificiales del Valle de las Higueras, Huecas, Toledo. Trabajos de Prehistoria 62, 67–90. Burbidge, C.I., Sanderson, D.C.W., Housley, R.A., Allsworth Jones, P., 2007. Survey of Palaeolithic Sites by Luminescence Profiling, a Case Study from Eastern Europe. Quaternary Geochronology 2, 296–302. Burbidge, C.I., 2012. Facets of luminescence for dating. Spectroscopy Letters 45, 118–126. Burbidge, C.I., 2015. A broadly applicable function for describing luminescence dose response. Journal of Applied Physics 118, 044904. http://dx.doi.org/10.1063/1. 4927214. Burbidge, C.I., Duller, G.A.T., Roberts, H.M., 2006. De determination for young samples using the standardised OSL response of coarse grain quartz. Radiation Measurements 41, 278–288. Burbidge, C.I., Sanderson, D.C.W., Fülop, R., 2008. Luminescence Dating of Ditch Fills From the Headland Archaeology Ltd. Excavation of Newry Ring Fort, Northern Ireland, Glasgow, SUERC. University of Glasgow (91 pp). Burbidge, C.I., Trindade, M.J., Cardoso, G.J.O., Dias, M.I., Oosterbeek, L., Cruz, A., Scarre, C., Cura, P., Caron, L., Prudêncio, M.I., Gouveia, A., Franco, D., Marques, R., 2014. Luminescence dating and associated analyses in transition landscapes of the Alto Ribatejo, Central Portugal. Quaternary Geochronology 20, 65–77. Burleigh, R., Matthews, K., Ambers, J., 1982. British Museum natural radiocarbon measurements XIV. Radiocarbon 24, 229–261. Campano Lorenzo, A., Rodriguez Marcos, J.A., Sanz Mínguez, C., 1985. Apuntes para una primera valoración de la explotación y comercio de la variscita en la Meseta Norte. Anuario del Instituto de Estudios Zamoranos Florián de Ocampopp. 13–22. Cardoso, J.L., 2010. O povoado calcolítico da Penha Verde (Sintra). Estudos Arqueológicos de Oeiras 18, 467–551. Cardoso, J.L., 2014. Cronología absoluta del fenómeno campaniforme al Norte del estuario del Tajo: implicaciones demográficas y sociales. Trabajos de Prehistoria 71, 56–75. Cardoso, J.L., Caninas, J.C., 2010. Moita da Ladra (Vila Franca de Xira). Resultados preliminares da escavação integral de um povoado calcolítico muralhado. In: Gonçalves, V.S., Sousa, A.C. (Eds.), Transformação E Mudança No Centro E Sul de Portugal: O 4.o E O 3.o Milénios A.n.e. (Cascais, 2005), pp. 65–95 (Cascais, Cascais). Cardoso, J.L., Carreira, J.R., Ferreira, O. da V., 1996. Novos elementos para o estudo do Neolítico antigo da região de Lisboa. Estudos Arqueológicos de Oeiras 6, 9–26. Castro Martínez, P.V., Lull, V., Mico, L.R., 1996. Cronología de la Prehistoria Reciente de la Península Ibérica y Baleares (c. 2800–900 cal ANE). Archaeopress, Oxford. Collet, H., 2004. Les Mines Neolithiques de Spiennes —Etat Des Connaissances et Perspectives de Recherche., 2004. Actes Du XIVème Congrès de l'UISPP. Bar International series 1303. Archaeopress, Oxford. Collet, H., Hauzeur, A., Lech, J., 2008. The prehistoric flint mining complex at Spiennes (Belgium) on the occasion of its discovery 140 years ago. In: Allard, P., Bostyn, F., Giligny, F., Lech, J. (Eds.), Flint Mining in Prehistoric Europe Interpreting the Archaeological RecordsBAR International Series 1891. Archaeopress, Oxford. Costa, M.E., García Sanjuán, L., Murillo-Barroso, M., Parrilla Giráldez, R., Wheatley, D.W., 2011. Artefactos elaborados en rocas raras en los contextos funerarios del IV–II milenios cal ANE en el sur de España: Una revisión. Menga 1, 253–294. Craddock, P.T., 1995. Early Metal Mining and Production. Edinburgh University Press, Edinburgh. de Blas Cortina, M.A., 1998. Producción e intercambio de metal: la singularidad de las minas de cobre prehistóricas de El Aramo y El Milagro (Asturias). In: Delibes, G. (Ed.), Minerales y metales en la Prehistoria Reciente. Algunos testimonios de su explotación y laboreo en la península ibérica. Universidad de Valladolid, Valladolid, pp. 71–103. 174 C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 de Blas Cortina, M.A., 2011. Las minas prehistóricas del norte de España en el contexto de la paleominería del cobre del Occidente de Europa. In: Mata-Perelló, J.M., Torró, L., Fuentes, N.M. (Eds.), Actas del V Congreso Internacional sobre minería y Metalurgia Históricas en el Suroeste Europeo. SEDPGYM, MADRID, pp. 101–130. Deckers, K., Sanderson, D.C.W., Spencer,J.Q., 2005. Thermoluminescencescreening of nondiagnostic sherds from stream sediments to obtain apreliminary alluvial chronology: an example from Cyprus. Geoarchaeology 20, 67–77. Delibes de Castro, G., Rojo Guerra, M.Á., 1997. C14 y Secuencia megalítica en la Lora Burgalesa: Acotaciones a la problemática de las dataciones absolutas referentes a yacimientos dolménicos. In: Rodríguez Casal, A.A. (Ed.), O neolitico atlántico e as orixes do megalitismo. Universidad de Santiago de Compostela, Santiago de Compostela, pp. 391–415. Dias, M.I., Prudêncio, M.I., 2007. Neutron activation analysis of archaeological materials: an overview of the ITN NAA laboratory, Portugal. Archaeometry 49, 383–393. Dias, M.I.,Prudêncio, M.I., Matos, M.A., Rodrigues, A.L., 2013. Tracing the originof blue and white Chinese Porcelain ordered for the Portuguese market during the Ming dynasty using INAA. Journal of Archaeological Science 40 (7), 3046–3057. http://dx.doi.org/ 10.1016/j.jas.2013.03.00. Díaz del Rio, P., Consuegra Rodríguez, S., 2011. Time for action. The chronology of mining events at Casa Montero (Madrid, Spain). In: Capote,M., Consuegra, S., Díaz-del-Río, P., Terradas, X. (Eds.), Proceedings of the 2nd International Conference of the UISPP Commission on Flint Mining in Preand Protohistoric Times. Archaeopress, Oxford, pp. 221–229. Díaz delRio, P., Consuegra Rodríguez, S., Capote, M., Castañeda, N., Criado, C., Vicent García, J.M., Orozco Köhler, T., Terradas Batlle, X., 2008. Estructura, contexto y cronología de la mina de sílex de Casa Montero (Madrid). IV Congreso del Neolítico Peninsular. Museo Arqueológico de Alicante-MARQ, Alicante, pp. 200–207. Domergue, C., 1990. Les mines de la péninsule Ibérique dans l'Antiquité Romaine, Collection de l'Ecole Française de Rome. École française de Rome, Roma. Dominguez Bella, S., 1996. Caracterización mineralógica y petrológica de algunos objetos del ajuar y de los recubrimientos de las paredes y suelos de la cámara (materiales líticos y ocres). In: Ramos Muñoz, J., Giles Pacheco, F. (Eds.), El Dolmén de Alberite (Villamartin). Aportaciones a Las Formas Económicas Y Sociales de Las Comunidades Neolíticas En El Noroeste de Cádiz. Servicio de PUblicaciones de la Universidad de Cádiz, Cádiz, pp. 187–206. Dominguez Bella, S., 2004. Variscite, a prestige mineral in the Neolithic–Aneolithic Europe. Raw material sources and possible distribution routes. Slovak Geological Magazine 10, 147–152. Dominguez Bella, S., 2012. Archaeomineralogy of prehistoric artifacts and gemstones. In: Herrero, J.M., Vendrell-Saz, M. (Eds.), Sociedad Española de Mineralogía. Museo Geominero del Instituto Geológico y Minero de España, España, pp. 5–28. Dominguez Bella, S., Bóveda, M.J., 2011. Variscita y ámbar en el Neolítico gallego. Análisis arqueométrico del collar del túmulo 1 de Chousa Nova, Silleda (Pontevedra, España). Trabajos de Prehistoria 68, 369–380. http://dx.doi.org/10.3989/tp.2011.11075. Edo i Benaiges, M., Fernández Turiel, J.L., 1997. Las cuentas de collar de calaita del dolmen del Prado de las Cruces. Bernuy-Salinero (Ávila). In: Fabián García, J.F. (Ed.), El Dolmen Del Prado de Las Cruces. Bernuy-Salinero (Ávila). Junta de Castilla y León, Valladolid. Edo i Benaiges, M.,Blasco, A., Villalba, M.J., 1990. Approche de la carte de distribution de la variscite de can Tintorer, Gavà (Catalogne). Cahiers du Quaternaire 17, 287–298. Edo i Benaiges, M., Villalba, M.J., Blasco, A., 1995a. La Calaíta en la Península Ibérica. In: Jorge, V.O. (Ed.), 1o Congresso de Arqueologia PeninsularTrabalhos de Antropología e Etnología. Sociedade portuguesa de Antropologia e Etnologia, Porto, pp. 127–168. Edo i Benaiges, M., Blasco, A., Villalba, M.J., Gimeno, D., Fernández Turiel, J.L., Plana, F., 1995b. La caracterización de la variscita del complejo minero de Can Tintorer, una experiencia aplicada al conocimiento del sistema de bienes de prestigio durante el neolítico. In: Bernabeu, J., Orozco Köhler, T., Terradas, X. (Eds.), Los Recursos Abióticos En La Prehistoria. Caracterización, Aprovisionamiento E Intercambio. Universitat de Valencia, pp. 83–110. Esparza Arroyo, A., Larrazabal Galarza, J., 2000. El castro de la Mazada (Zamora): elementos metálicos y contexto peninsular. In: Oliveira Jorge, V. (Ed.), 3o Congresso de Arqueología Peninsular: UTAD, Vila Real, Portugal, Setembro de 1999. ADECAP, Porto, pp. 433–476. Fabián García, J.F., 2006. El IV y III milenio AC en el Valle Amblés (Ávila). Junta de Castilla y León, Valladolid. FernándezTuriel,J.L., Gimeno, D., Cabañas, M., LópezSoler, A., 1996. Análisis de materiales arqueológicos mediante ablación por Laser-ICP-MS. In: I Congrés del Neolític a laPenínsula Ibérica. Formació i implantació de les comunitats agrícoles vol. 1.Museu de Gavà, Barcelona, pp. 223–225. Forestier, F.H., Lasnier, В., L'Helgouach, J., 1973a. À propos de la “callaïs”,découverted'un gisement de variscite à Pannecé (Loire-Atlantique), analyse de quelques “perles vertes”néolithiques. Bulletin de la Société Préhistorique Française 70, 173–180. Forestier, F.H., Lasnier, В., L'Helgouach, J., 1973b. Découverte de minyulite en échantillons spectaculaires, de wavellite et de variscite dans les phtanites siluriens près de Pannecé (Loire-Atlantique). Bulletinde la Société Minéralogique de Cristallographie 96, 67–71. Frumkin, A., Bar-Matthews, M., Davidovich, U., Langford, B., Porat, R., Ullman, M., Zissu, B., 2014. In-situ dating of ancient quarries and the source of flowstone (“calcitealabaster”) artifacts in the southern Levant. Journal of Archaeological Science 41, 749–758. http://dx.doi.org/10.1016/j.jas.2013.09.025. García-Guinea, J., Sapalski, C., Cardenes, V., MLombardero, M., 2000. Mineral inlays in natural stone slabs: techniques, materials and preservation. Construction and Building Materials 14, 365–373. Gonçalves, V.S., 2002. Quelques questions autor du temps, de l'espace et des symboles mégalithiques du Centre et du Sud Poryugal. Origine et Développement Du Mégalithisme de L'ouest de l'Europe (Bougon - 26/30 Octobre 2002), pp. 485–830. Gonçalves, V.S., 2003. A Anta 2 da Herdade dos Cebolinhos (Reguengos de Monsaraz, Évora): sinopse das intervenções de 1996–97 e duas datações de radiocarbono para a última utilização da Câmara ortostática. Revista Portuguesa de Arqueología 8, 143–188. Gonçalves, V.S., 2005. Cascais há 5000 mil anos. Tempos, símbolos e espaços da Morte das antigas Sociedades Camponesas. Cámara Municipal de Cascais, Cascais. Gonçalves, Victor S., 2008. As Ocupações Pré-Históricas Das Furnas Do Poço Velho (Cascais). Cámara Municipal de Cascais, Cascais. Gonçalves, A.A.H. de B., Reis, M. de L., 1982. Estudo mineralógico de elementos de adorno de cor verde provenientes de estações arqueológicas portuguesas. Portugalia Nova série 2–3, 153–166. Gouveia, M.A., Prudêncio, M.I., 2000. New data on sixteen referencematerials obtained by INAA. Journal of Radioanalytical and Nuclear Chemistry 245, 105–108. Guitán Rivera, F., Vázquez-Varela, J.M., 1975. Análisis radiográfico de cuentas de calaíta gallegas. Boletín de la Comisión de Monumentos de Lugo 9, 187–188. Gutiérrez Pérez, J., Villalobos García, R., Odriozola, C.P., 2015. El uso de la variscita en Hispania durante a Época Romana. Análisis de composición de objetos de adorno y teselas de la zona noroccidental de la Meseta Norte. SPAL 24, 165–181. Herbaut, F., Querré, G., 2004. La parure néolithique en variscite dans le sud de l'Armorique. Bulletin de la Société préhistorique française 101, 497–520. http://dx. doi.org/10.3406/bspf.2004.13029. Hunt, M., 1996. Prospección arqueológica de carácter minero y metalúrgico: fuentes y restos. Acontia 2, 19–28. Hunt, M., 2003. Prehistoric Mining and Metallurgy in South-West Iberian Peninsula. Archaeopres, Oxford. Jiménez Gómez, M.C., 1995. Zambujal. Los amuletos de las campañas 1964 hasta 1973. In: Sangmeister, E., Jiménez Gómez, M.C. (Eds.), Zambujal: Kupferfunde Aus Den Grabungen 1964 Bis 1973 —Los Amuletos de Las Campañas 1964 Hasta 1973. Philipp von Zabern, Mainz am Rhein, pp. 155–238. Jubes, E., Carbonell, A., 1920. Estudio geológico–industrial de los yacimientos minerales del término municipal de Encinasola y la Contienda de Moura (Portugal). Boletín Oficial de Minas y Metalúrgia 34–38. Kunst, M., Lutz, N., 2011. Zambujal (Torres Vedras), Investigações até 2007. Parte 1: Sobre a precisão da cronologia absoluta decorrente das investigações na quarta linha da fortificação. Estudos Arqueologicos de Oeiras 18, 419–466. Larsen, E.S., 1942. The mineralogy and paragenesis of the variscite nodules from Near Fairfield, Utah part 1. American Mineralogist 27, 281–300. Lheur, C., 1993. Les minéralisations de l'ancienne carrière de La Floquerie prèsde Pannecé (Loire-Atlantique). Le Cahier des Micromonteurs 4, 14–21. Linares Catela, J.A., García Sanjuán, L., 2010. Contribuciones a la cronología absoluta del megalitismo andaluz. Nuevas fechas radiocarbónicas de sitios megalíticos del Andévalo oriental (Huelva). Menga 1, 134–151. Marini, C., Gimeno, D., Sistu, G., 1989. Le mineralizzazioni a variscite del Sarrabus. Bollettino della Societa Geologica Italiana 108, 357–367. Massé, R., 1971. Découvert de minyulite, wavellite et variscite dans les phtanites de Pannecé. Bulletin de la Société Sciences naturelles Ouest de la France LXIX, 12–15. Meireles, C., Ferreira, N., Lourdes Reis, M., 1987. Variscite occurrences in Silurian Formations from Northern Portugal. Comunicações dos Serviços Geológicos de Portugal 73, 21–27. Moro, M.C., Cembranos Pérez, M.L., Fernández Fernández, A., 1995. Estudio mineralógico de las variscitas y turquesas silúricas de Punta Corveiro (Pontevedra, Españ). Geogaceta 18, 176–179. Murillo-Barroso, M., Martinón-Torres, M., 2012. Amber sources and trade in the prehistory of the Iberian Peninsula. European Journal of Archaeology 15, 187–216. Murillo-Barroso, M., Montero Ruiz, I., 2012. Copper ornaments in the Iberian Chalcolithic: technology versus social demand. Journal of Mediterranean Archaeology 25, 53–73. Murray, A.S., Wintle, A.G., 2000. Luminescence dating of quartz using an improved singlealiquot regenerative-dose protocol. Radiation Measurements 32, 57–73. Nocete, F., Linares, J.A., 1999. Las primeras sociedades mineras en Huelva. Alosno. Historia de La Provincia de Huelva. Madrid, pp. 49–64. Odriozola, C.P., 2014. A new approach to determine the geological provenance of variscite artifacts using the P/Al atomic ratios. Archaeological and Anthropological Sciences 6, 1–22. http://dx.doi.org/10.1007/s12520-014-0195-2. Odriozola, C.P., Villalobos García, R., 2015. La explotación de variscita en el Sinforme de Terena: el complejo minero de Pico Centeno (Encinasola, Huelva). Trabajos de Prehistoria 72 (2). Odriozola, C.P., Hurtado, V., Dias, M.I., Prudêncio, M.I., 2008. Datación por técnicas luminiscentes de la tumba 3 y el conjunto campaniforme de La Pijotilla (Badajoz, España)./ Luminiscence Dating of Burial 3 and the Bell Beaker pottery from La Pijotilla (Badajoz, Spain). VIII Congreso Ibérico de Arqueometría. ACTAS. Instituto de Historia (CSIC), Museo Arqueológico Nacional y SAPaC, pp. 211–225. Odriozola, C.P., Linares Catela, J.A., Hurtado, V., 2010. Variscite source and source analysis: testing assumptions at Pico Centeno (Encinasola, Spain). Journal of Archaeological Science 37, 3146–3157. Odriozola, C.P., Burbidge, C.I., Dias, M.I., Hurtado, V., 2014. Dating of Las Mesas Copper Age walled enclosure (La Fuente, Spain). Trabajos de Prehistoria 71, 343–352. Oliveira, J., 2000. O megalitismo de xisto da Bacia do Sever (Montalvão–Cedillo). In: Gonçalves, V.S. (Ed.), Muitas Antas, Pouca Gente?Instituto Português de Arqueología, Lisboa. Oliveira, J., 2010. Neolítico e megalitismo na Coudelaria de Alter. Transformação E Mudanza No Centro E Sul de Portugal: O 4.o E O 3.o Milénios A.n.e. Cámara Municipal de Cascais, Cascais. Pavón Soldevila, I., 1994. El mundo funerario de la edad del bronce en la Tierra de Barros: una aproximación desde la bio-arqueología de Las Minitas. Mem. Campaña Urgenc. De 2008-141. Pérez Macías, J.A., 2008. Recursos minerales de cobre y minería prehistórica en el suroeste de España. Verdolay 11, 9–36. 175C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176 Pérez Macías, J.A., 2011. Las minas de Encinasola (Huelva). La explotación de un campo filoniano de Ossa Morena. De Re Metallica 16, 1–10. Pétrequin, P., Errera, M., Petrequin, A.-M., Allard, P., 2006. The Neolithic Quarries of Mont Viso, Piedmont, Italy: initial radiocarbon dates. European Journal of Archaeology 9, 7–30. Prescott, J.R., Hutton, J.T., 1988. Cosmic-ray and gamma-ray dosimetry for TL and electron-spin-resonance. Nuclear Tracks and Radiation Measurements 14, 223–227. Prescott, J.R., Stephan,L.G., 1982. The contribution of cosmic radiation to the environmental dose for thermoluminescent dating. Latitude, altitude and depth dependencies. Council of Europe PACT Journal 6, 17–25. Prudêncio, M.I., Oliveira, F., Dias, M.I., Sequeira Braga, M.A., Delgado, M., Martins, M.,2006. Raw materials sources used for the manufacture of Roman “Bracarense”ceramics from NW Iberian Peninsula. Clays and Clay Minerals 54 (5), 639–651. Querré, G., Herbault, F., Calligaro, T., 2008. Transport of Neolithic variscites demonstrated by PIXE analysis. X-Ray Spectrometry 37, 116–120. Querré, G., Calligaro, T., Domínguez-Bella, S., Cassen, S., 2014. PIXE analyses over a long period: the case of Neolithic variscite jewels from Western Europe (5th–3th millennium BC). Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 318, 149–156. Real, Fernando, 1992. Estudo Mineralógico de Adornos de Cor Verde Do Neolítico Antigo Da Gruta Do Caldeirão. In: Zilhão, João (Ed.), Gruta Do Caldeirão O Neolítico Antigo. Lisboa: Trabalhos de Arqueología 6, Instituto Português do Patrimonio Arquitectónico e Arqueológico. Departamento de Arqueología, pp. 315–319. Reimer, P.J., Edouard Bard, A.B., Beck, J.W., Blackwell, P.G., Ramsey, C.B., Buck, C.B., et al., 2013. IntCal13 and Marine13 radiocarbon age calibration curves 0–50,000 years cal BP. Radiocarbon 55, 1869–1887. http://dx.doi.org/10.2458/azu_js_rc.55.16947. Roberts,H.M.,Duller,G.A.T.,2004.Standardised growth curves for optical dating of sediment using multiple grain aliquots. Radiation Measurements 38, 241–252. Rodrigues, A.L., Burbidge, C.I., Dias, M.I., Rocha, F., Valera, A., Prudêncio, M.I., 2013. Luminescence and mineralogy of profiling samples from negative archaeological features. Mediterranean Archaeology and Archaeometry 13 (3), 37–47. Rojo Guerra, M.Á., Delibes de Castro, G., Edo i Benaiges, M., Fernández Turiel, J.L., 1996. Adornos de calaíta en los ajuares dolménicos de la provincia de Burgos: Apuntes sobre su composición y procedencia. I Congrés del Neolític a la Península Ibérica. Rubricatum 1, 239–250. Rothenberg, B., Frejeiro, A.B., 1980. Ancient copper mining and smelting at Chinflón (Huelva SW Spain). British Museum Occasional Papers 20, 41–62. Sanderson, D.C.W., Murphy, S., 2009. Using simple portable OSL measurements and laboratory characterisation to help understand complex and heterogeneous sediment sequences for luminescence dating. Quaternary Geochronology 20, 893–900. Sanderson, D.C.W., Bishop, P., Houston, I., Boonsener, M., 2001. Luminescence characterisation of quartz-rich cover sands from NE Thailand. Quaternary Science Reviews 20, 893–900. Santos Arevalo, F.J., Gómez Martínez, I., Garcia Leon, M., 2009. Radiocarbon measurement programme at the Centro Nacional de Aceleradores (CNA). Radiocarbon 883–889. Sanz Mínguez, C., Campano Lorenzo, A., Rodríguez Marcos, J.A., 1990. Nuevos datos sobre la dispersión de la variscita en la Meseta Norte: las explotaciones de época romana. Primer Congreso de Historia de ZamoraTomo 2. Prehistoria E Historia Antigua. Instituto de Estudios Zamoranos Florián de Ocampo, Zamora, pp. 747–764. Schiffer, M.B., 1986. Radiocarbon dating and the “old wood”problem: the case of the Hohokam chronology. Journal of Archaeological Science 13, 13–30. http://dx.doi. org/10.1016/0305-4403(86)90024-5. Schubart, H., Pingel, V., Kunter, M., Liesau von Lettow-Virbeck, C., Pozo, M., Medina, J.A., Casas, J., Tresserras, J.J., Hägg, I., 2004. Studien zu Grab 111 von Fuente Álamo (Almería). Madrider Mitteilungen 45, 57–146. Schuhmacher, T.X., 2012. El marfil en España desde el Calcolítico al Bronce Antiguo. In: Banerjee, A., López Padilla, J.A., Schuhmacher, T.X. (Eds.), Elfenbeinstudien faszikel 1. Marfiles y elefantes en la península Ibérica y el Mediterráneo Occidental, Iberia Archaeologica. Mainz, Verlag Philipp von Zabern, pp. 45–68. Schuhmacher, T.X., Cardoso, J.L., Banerjee, A., 2009. Soucing African ivory in Chalcolithic Portugal. Antiquity 83, 983–997. Senna-Martínez, J.C., Quintã Ventura, J.M., 2000. Os primeiros constructores de megalitos. En: Por Terras de Viriato. Arqueologia Da Região de Viseu. Museo Nacinal de Arqueologia, Viseu. Shepherd, R., 1980. Prehistoric Mining and Allied Industries, Studies in Archaeological Science. Academic Press, London. Silva, A.M., 2003. Evidence of osteochronditis dissecans in late neolithic/chalcolithic Portuguese populations. Dónde Estamospp. 464–468. Silva, A.M., Wasterlain, S.N., 2010. A possible case of an ossifying fibroma in a Late Neolithic population from Portugal. International Journal of Osteoarchaeology 20, 579–585. Soares, J., 2010. Dólmen da Pedra Branca. Datas radiométricas. Musa. Museus, Arqueologia e Outros Patrimónios 3, 71–82. Soares, J., SIlva, C., 2010. Anta Grande do Zambujeiro —arquitectura e poder. Intervenção arqueológica do MAEDS, 1985–87. Musa. Museus, Arqueologia e Outros Patrimónios 3, 83–129. Sousa, A.C., 2010. Penedos e muralhas. A leitura possível das fortificaçoes do Penedo do Lexim. In: Gonçalves, V.S., Sousa, A.C. (Eds.), Transformação E Mudanza No Centro E Sul de POrtugal: O 4.o E O 3.o Milénios A.n.e. Cámara Municipal de Cascais, Cascais. Sttip, J.J., Tamers, M.A., 1996. Dataciones absolutas. In: Ramos Muñoz, J., Giles Pacheco, F. (Eds.), El Dolmen de Alberite (Villamartín). Aportaciones a Las Formas Económicas Y Sociales de Las Comunidades Neolíticas En El Noroeste de Cádiz. Servicio de publicaciones de la Universidad de Cádiz, Salamanca, pp. 179–186. Stuiver, M., Polach, H.A., 1977. Discussion: reporting 14C data. Radiocarbon 19, 255–363. Stuiver, M., Reimer, P.J., 1993. Extended 14C data base and revised CALIB 3.0 14C age calibration program radiocarbon. Radiocarbon 35, 215–230. Tarriño,A., Lobo, P.J.,García-Rojas,M.,Elorrieta,I.,Orue,I.,Bento-Calvo, A.,Karampanglidis, T., 2011. Introducción al estudio de las minas neolíticas de sílex de la Sierra de Araico (Condado de Treviño): campaña de excavación del 2011. Estudios de Arqueología Alavesa. 27, 4–81. Trindade, M.J., Prudêncio, M.I., Burbidge, C.I., Dias, M.I., Cardoso, G., Marques, R., Rocha, F., 2013. Distribution of naturally occurring radionuclides (K, Th and U) in weathered rocks of various lithological types from the uranium bearing region of Fornos de Algodres, Portugal. Mediterranean Archaeology and Archaeometry (ISSN: 1108-9628) 13 (3), 71–79. Trindade, M.J., Prudêncio, M.I., Burbidge, C.I., Dias, M.I., Cardoso, G., Marques, R., Rocha, F., 2014. Study of an aplite dyke from the Beira uraniferous province in Fornos de Algodres area (Central Portugal): trace elements distribution and evaluation of natural radioactivity. Applied Geochemistry 44, 111–120. Valera, A.C., Silva, A.M., Márquez Romero, J.E., 2014. La temporalidad del recinto de fosos de Perdigões: cronología absoluta de estructuras y prácticas sociales. Spal 23, 11–26. http://dx.doi.org/10.12795/spal.2014i23.01. Villalba, M.J., 2002. Le gîte de variscite de Can Tintorer: production, transformation et circulation du minéral vert. In: Guilaine, J. (Ed.), Matériaux, Productions, Circulations Du Neolithique À l'Age Du Bronze. Séminaire Du Collège Du France, Errance, Paris, pp. 115–130. Villalba, M.J., Edo i Benaiges, M., Blasco, A., 2001. La callaïs en Europe du Sud-Ouest. État de la question. In: Le Roux, C.-T. (Ed.), Du monde des chasseurs à celui des métallurgistes, Revue Archéologique de l'Ouest. Suppléments. Université Rennes I, pp. 267–276. Villalobos García, R., 2012. Adornos exóticos en los sepulcros tardoneolíticos de la Submeseta Norte Española. El ejemplo de Las Tuerces como nodo de una red descentralizada de intercambiosActes Xarxes al Neolític. Museu de Gavà, Gavà (Barcelona), pp. 265–271. Villalobos García, R.,2014. The megalithic tombs of the Spanish Northern Meseta.Material, political and ideological tie between the Neolithic people and their territory. Colloque Internationel Fonctions, Utilisations et Représentations de L'espace Dans Les Sépultures Monumentales Du Néolithique EuropéenPréhistoires Méditerranéennes, s4. Maison Méditerranéenne Des Sciences de L'homme. CNRS, Université de Provence, Aix-en-Provence. Virgilio Sevillano, F., 1978. Testimonio arqueológico de la provincia de Zamora. Instituto de Estudios Zamoranos “Florian do Campo”, Zamora. Waterman, A.J., 2012. Marked in Life and Death: identifying Biological Markers of Social Differentiation in Late Prehistoric Portugal. Weisgerber, G., Willies, L., 2000. The use of fire in prehistoric and ancient mining: firesetting. Paléorient 131–149. Whittle, A.W.R., Healy, F.M.A., Bayliss, A., 2011. Gathering Time: Dating theEarly Neolithic Enclosures of Southern Britain and Ireland. Oxbow Books. Willies, L., 1994. Firesetting technology. Bulletin of the Peak District Mines Historical Society 12. 176 C.P. Odriozola et al. / Quaternary Research 85 (2016) 159–176