A multi-analytical study of the Montelirio beaded attires: Marine resources, sumptuary crafts, and female power in copper age Iberia

Sanjuán et al., Sci. Adv. 11, eadp1917 (2025) 29 January 2025 Science AdvAnceS | ReSeARch ARticle 1 of 14 ANTHROPOLOGY A multianalytical study of the Montelirio beaded attires: Marine resources, sumptuary crafts, and female power in copper age Iberia Leonardo García Sanjuán1, Samuel RamírezCruzado1*, Marta DíazGuardamino2, José Antonio Lozano Rodríguez3,4, Teodosio Donaire Romero5, José Ángel Afonso Vargas6, Carlos RodríguezRellán7, Verónica Balsera Nieto8, Luis M. Cáceres Puro5, David W. Wheatley9, Timothy Earle10, Marta CintasPeña1, Juan Manuel Vargas Jiménez11, Álvaro Fernández Flores12, Miriam Luciañez Triviño13, Juan CárdenasPárraga7, María Martínez Merino1, Fernando Muñiz Guinea14,15 Excellent indicators of technology, social organization, exchange patterns, and even beliefs, beads are a topic of research in their own right. Findings made between 2010 and 2011 at the Montelirio tholos burial, part of the Valencina Copper Age megasite, in southwestern Spain, revealed what amounts to the largest singleburial everdocumented assemblage of beads. Furthermore, the Montelirio beads were part of unparalleled beaded attires worn by some of the people buried in the grave, mostly females. A multianalytical study undertaken over the past 5 years—including a meticulous quantification of the collection, the characterization of the raw materials, radiocarbon dating and chronometric statistical modeling, morphometric analysis, phytolith analysis, experimental work and contextual analysis—reveals several previously unidentified aspects of these remarkable creations. This includes the role of the attires as sumptuary attributes heavily loaded of symbolism, used by a selected group of women of high social significance. INTRODUCTION Here, we study a large collection of discoidal perforated beads from the Montelirio tholos tomb and neighboring Structure 10.042–10.049 (also referred to as “The Ivory Lady” grave). Since they were excavated between 2007 and 2010 and then studied in publications including a monograph (1) and several papers [(2–7), etc.] these two tombs have, in barely a decade, become a paradigm of some of the main features associated with the Iberian Copper Age: economic intensification, emerging social complexity, supraregional connectivity, sophisticated monumentality, lavish material culture, and artistic exuberance. Both tombs are part of the Valencina de la ConcepciónCastilleja de Guzmán (henceforth Valencina) megasite, which, located in southwesten (SW) Spain (Fig. 1) and spreading over an area of c. 450 ha in the northern El Aljarafe plateau, barely 6 km from the city center of modernday Sevilla, has itself become a major reference for the study of third millennium BC Europe (8–11). Over the past two decades, diverging interpretations have been put forward to interpret Valencina as a site, including it being a permanently occupied village acting as seat of a centralized statelevel polity, a lowdensity settlement with shifting foci of occupation, a central place used for seasonal or periodical gatherings involving people living in the surrounding region (and further afield), a “cemetery,” or any combination of those [see (2) and (8) for a synthesis of this problem and further readings]. One chapter in the Montelirio monograph (12) offered a preliminary study of the remarkable beaded attires of this tomb. Here, a muchexpanded version of that study is presented based on a multidisciplinary approach that includes completely new elements such as quantification, biogeological characterization, morphometric analysis, radiocarbon dating and modeling, archaeobotanical analysis, experimental work, and some theoretical consideration. The main specific aims of this study are: (i) to quantify the bead assemblage reliably in order to understand the labor investment inherent to it and compare it with other major collections of beads, worldwide; (ii) to establish the chronology of the beads to understand their synchronicity (or otherwise) with the people buried in the tomb; (iii) to characterize the raw materials involved in the making of the beads and attires; and (iv) to understand the technical process involved through experimental archeology and phytolith analysis (intended to identify possible traces of the fibers the beads were weaved with). In general, in this work, we ask how and when these garments were made, what social and cultural context gave rise to these exceptional attires, and what are the implications of the technical aspects of these garments for our understanding of CopperAge society. RESULTS Quantification The location of the beaded attires within the large chamber (LC) of Montelirio and the individuals who wore them, mostly females (13), 1department of Prehistory and Archaeology, University of Seville, Seville, Spain. 2department of Archaeology, durham University, durham, UK. 3canary islands Oceanographic center (cOc), Spanish institute of Oceanography (ieO), Spanish Research council (cSic), Santa cruz de tenerife, Spain. 4department of history and Philosophy, Area of Prehistory, University of Alcalá (UAh), Alcalá de henares, Spain. 5department of earth Sciences, University of huelva, huelva, Spain. 6department Animal Biology, edaphology and Geology, University of la laguna, Santa cruz de tenerife, Spain. 7department of Prehistory and Archaeology, University of Granada, Granada, Spain. 8instituto de la Juventud, Ministerio de derechos Sociales y Agenda 2030, Madrid, Spain. 9department of Archaeology, University of Southampton, Southampton, UK. 10department of Anthropology, northwestern University, evanston, il, USA. 11Servicio de Arqueología, Ayuntamiento de valencina de la concepción, valencina de la concepción, Seville, Spain. 12Arqueología y Gestion S.l.l., Seville, Spain. 13conservation/Restoration Section, department of Painting, University of the Basque country UPv/ehU, vizcaya, Spain. 14department of crystallography, Mineralogy and Agricultural chemistry, Faculty of chemistry, University of Seville, Seville, Spain. 15MUGUS, Museum of Geology of the University of Seville, Seville, Spain. *corresponding author. email: samramagu@ alum. us. es copyright © 2025 the Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. no claim to original U.S. Government Works. distributed under a creative commons Attribution license 4.0 (cc BY). Downloaded from https://www.science.org on March 29, 2025 Sanjuán et al., Sci. Adv. 11, eadp1917 (2025) 29 January 2025 Science AdvAnceS | ReSeARch ARticle 2 of 14 are shown in Figs. 2 and 3. Basically, three types of textiles were identified: full body tunics (worn only by individuals UE343 and UE102), skirts, and cloths of undetermined shape. The excavation involved a painstaking process by which the attires were individualized and, in some cases, consolidated in situ. In Structure 10.042–10.049, located barely 100m north of Montelirio, more than 2000 beads were found scattered in the corridor and the first chamber (which was largely destroyed). A small group of 90 beads were found in the upper level of the second chamber (Structure 10.049), in connection with a rock crystal blade dagger, of whose ivory handle the beads are believed to have been a decoration (4). As it was presented to us in the Sevilla Archaeology Museum in July 2019, the Montelirio assemblage of beads was stored in 51 containers (Fig. 4A). The beads were heavily mixed with soil from the infill of the tomb. Therefore, to quantify the material, the first job was to remove the soil mixed with the beads. A description of the procedure used is provided in Materials and Methods. Work involved seven people and approximately 651 human hours over 3 weeks. Once the cleaning was completed (Figs. 4, B and C; 5; and 6), samples of the soil attached to the beads were taken for phytolith analysis (see below), and the materials were weighed, resulting in 6.93 kg of dirt and stones (which were removed from the beads) and 11.13 kg of beads, including 7.71 kg from LC and 3.42 kg from the small chamber (SC), as well as 0.46 kg from the tomb of The Ivory Lady. A nontrivial amount of the beads found in Montelirio (particularly those of the attire worn by Individual UE 343, individual 111, and cloth 339) were consolidated in situ during the excavation and then transported as blocks to the museum (a 3D model of individual EU343 is available at https://skfb.ly/o7oWO). For this reason, they could not be weighed individually. Therefore, while 11.3 kg of beads was cleaned, weighed, and recorded in the museum, a more accurate overall figure for the total Montelirio assemblage would be between 13 and 15 kg. Next, samples were selected to estimate the total number of beads included in the assemblage and collect morphometric data (see below). Three samples were selected (see description in Materials and Methods). The first sample (Montelirio LC) produced weights between 0.19 and 0.01 g, with an average of 0.0708 g per bead, while the second (SC), with markedly smaller beads, yielded weights between 0.05 and 0.008 g, and an average of 0.0319 g per bead. On the basis on the total weight recorded divided by the average weight of individual beads, the estimated number of beads included in the assemblage is as follows: for the LC (7.71 kg), 108,898 beads; for the SC (3.42 kg), 107,210 beads. In total, 216,108 beads. This count, however, does not include the beads that were consolidated in situ and are kept separately in the museum, including especially individual UE343. On the basis of an approximate weighting (excluding the wooden frame that holds the consolidate material and other elements), this material would amount to a further 3.87 kg of beads, that is to say, another 54,661 beads. Together, the entire Montelirio bead collection would amount to a remarkable 270,769 beads. This figure, which excludes the beads from Structure 10.042–10.049, probably sets the Montelirio bead assemblage as the largest ever recorded worldwide, as discussed below. Identification Basically, three types of beads were identified: those made of marine shell and a very small fraction made of stone and bone. The arrangement of the ribs detected on some of the beads, and their form, either straight or slightly curved, made it possible to identify at least two families of bivalve species (Fig. 7). The first family, or Pectinidae, includes beads with wide, straight and subparallel ribs. There are several species belonging to this family that can be found on the Atlantic coasts of the southern Iberia, including Pecten maximus and Pecten jacobaeus (14). The organisms belonging to this family live buried or semiburied in the seabed, in shallow depressions, generally in places of fine, clean sand and sometimes in muddy Fig. 1. Location of the Valencina Copper Age mega-site in the Iberian Peninsula and the Montelirio tholos within the mega-site. (A) location of valencina in the iberian Peninsula and the Spanish southwest, showing middle holocene coastline. (B) location of Montelirio and PP4Montelirio Sector (with Structure 10.042–10.049) within the valencina de la concepcióncastilleja de Guzman megasite (highlighted in purple). the map base is the nationwide lidar coverage (0.5 points/m2) issued by the Spanish national Aerial Ortophotography Plan and freely available online (https://pnoa.ign.es/pnoalidar/presentacion). design: F. Sánchez díaz. Downloaded from https://www.science.org on March 29, 2025 Sanjuán et al., Sci. Adv. 11, eadp1917 (2025) 29 January 2025 Science AdvAnceS | ReSeARch ARticle 3 of 14 areas, between rocks and crevices (14,15). These organisms live in conditions of water salinity of not less than 25‰ (14). They are found at depths that range from 10 to 183 m, being most common on the marine substrate at depths of 20 to 45 m (14). As for the second family, Cardiidae, with narrow, slightly curved ribs, two possible genera were identified. Genus Acanthocardia includes five species, all of which occur in the Atlantic, namely, Acanthocardia aculeata, Acanthocardia echinata, Acanthocardia paucicostata, Acanthocardia spinosa, and Acanthocardia tuberculata. Species belonging to this genus can be found on wellsorted coarse or fine sandy, clayey sea beds, where they live buried (16,17). They are distributed in a range from 0 to 100 m depth (17,18), with the species A. tuberculata being very common at depths of 3 to 12 m on the Atlantic coasts of southern Iberia (16). On the other hand, two species of genus Cerastoderma were found, Cerastoderma edule and Cerastoderma glaucum, both of which can be found in the south Atlantic of Iberia (extracted from www.sealifebase.ca/). Individuals belonging to C. edule live buried at the bottom of shallow coastal areas and estuaries, in intertidal and subtidal zones composed of coarsefine sand, silts, and sandy silts (19). On the other hand, C. glaucum lives on the bottom of lagoons and mudflats in calm waters, made up of poorly cohesive sediments (fine sand), where wave action does not reach (19). It is possible to establish a range of 0to 50m depth in which these species are distributed, being more common at levels closer to the coast and affected by tides (extracted from www.sealifebase.ca/summary/ Cerastodermaedule.html; www.marlin.ac.uk/species/detail/1315). The species C. glaucum can tolerate higher salinity levels as it lives in environments with higher salt concentration than C. edule, being respectively 15 to 35‰ and 12.5 to 38.5‰ (19). Note that a small proportion of beads do not present the ornamentations typical of Pectinidae and Cardiidae. In some beads, the pearly layer (endostracum) of bivalves, commonly called mother of pearl, was recognized. In these, it is not possible to appreciate the characteristic iridescence of mother of pearl (possibly due to weathering or usewear), but it may point to the use of other bivalves such as those of the genus Ostrea and Anomia. In these genera, the iridescence of the inner layer is much more evident than in Pectinidae and Cardiidae. As for the beads made of stone, in much smaller numbers, 10 beads of different colorations and grain sizes were selected. The following rock types, commonly displaying dark tones and colors ranging from gray to green (Fig. 8), were identified: chloritoid schists (samples 51H and 6G), white micachlorite phyllites (samples 65H and 5G), gray to green shales (samples 24H, 1G, 2G, and 3G), a metasandstone (sample 4G), and a green limestone (sample 47H). Chloritoid schists have a Fig. 2. Distribution of the attires within the LC of Montelirio. design: M. luciañez triviño and Á. Fernández Flores [based on figure 3 in (12)]. Downloaded from https://www.science.org on March 29, 2025 Sanjuán et al., Sci. Adv. 11, eadp1917 (2025) 29 January 2025 Science AdvAnceS | ReSeARch ARticle 4 of 14 lepidoblastic texture and are composed of white mica + chlorite + chloritoid ± quartz ± rutile (Fig. 8A). The phyllites also show a lepidoblastic texture, and their main components are white mica + chlorite ± biotite ± albite ± quartz (Fig. 8B). Shales show a granolepidoblastic texture, and they are composed of white mica + quartz + chlorite ± calcite ± rutile (Fig. 8C). The green color of phyllites and shales is directly related to the chlorite content. The metasandstone has a less foliated fabric, a greater abundance of quartz than previous rocks, and smaller amounts of chlorite, white mica, and carbonates. Last, a greenish limestone with a detrital texture and some remains of fossil organisms, composed essentially of fragments of calcite and white mica, with quartz and goethite as accessory minerals (Fig. 8D), was observed. Both the accessory nature of the lithic beads and the diversity of rocks used suggests that they were not extracted from a quarry but were collected opportunistically where accumulated and mixed with materials of rather diverse composition. Therefore, these rocks were detached from their original outcrop, eroded during transport, and deposited on riverbanks or coastal areas. All these rocks can be found at relatively short distances from the Valencina Copper Age megasite. Chloritoid schists are rocks that, due to their mineralogy and the chemical composition of the chloritoid, can be related to equivalent rocks from the Cubito Formation. This geological formation is a highly deformed set of phyllites and schists outcropping north of the Aracena Massif (20). In addition to chloritoids, the chemical compositions of chlorites and white micas described in the schists and phyllites are also similar to those of the Cubito Formation (21). Gray to green shales, metasandstones, and limestones similar to those described have been observed around this geological formation [for example, in the Terena Formation, (22)], so the source area of all these materials could be located in the sector south of the OssaMorena Zone of the Iberian Massif (Northeast of Aracena). These rocks could have been transported by the numerous streams, such as the Rivera de Huelva, that drain this area and are tributaries of the Guadalquivir River. All this evidence suggest that these beads were made with local material. Morphometry The morphometric analysis of the Montelirio beads was mainly aimed at detecting differences in both their shape and/or size, looking at possible differences between the two chambers and their stratigraphic units (UE). The techniques used to achieve this are described in the Materials and Methods. The results revealed differences in the size of the beads according to their location within Montelirio and Structure 10.042– 10.049. This is evident in the average sizes, with the beads from the LC being noticeably larger and heavier than those recovered in Structure 10.042–10.049 and the SC of Montelirio (table S1). The nonparametric KruskalWallis test confirmed the statistical significance of these differences in terms of all the measures considered during the analysis (table S2). However, the Bonferroni post hoc correction (which analyses onetoone comparisons between pairs of sets) only partly qualified this conclusion, as statistical differences between the beads from Structure 10.042–10.049 and the Montelirio SC were not found in terms of both their maximum thickness and the maximum and minimum diameter of their perforations (table S3). The principal components analysis based on the geometric morphometric analysis (GMA) data suggests that most beads are relatively similar to each other, with a comparatively smaller number of them showing a greater variability (figs. S1 and S2). This is the case even after the removal of c. 100 outliers from the sample (fig. S3, A to D). This apparent similarity seems to be supported by the discrete success of the linear discriminant analysis, which was only able to correctly classify 34.9% of the beads, although this success varies from 65.7% for structure 10.042 to only 2.8% for UE 209 (table S4). However, other data derived from the GMA do indicate significant differences between the beads depending on the UE from which they originate. This is the case of the multivariate analysis of variance analysis (df: 5; HL: 0.62296; approximately F: 5.1532; num. Df: 380; den. Df: 15717; Pr(>F): < 2.2 × 10−16) or the Haralick’s circularity. The latter is particularly interesting, as it evaluates how far the shape of an object is from being a perfect circle (the higher the value, the closer) (23). In the case of the Montelirio beads, circularity can be used as a proxy for the level of “perfection” or standardization achieved during their manufacturing process. The results (fig. S3E) show that the beads from Structure 10.049 and—especially—10.042 have not only an average circularity significantly higher than the rest of the UEs but also a considerably higher degree of internal variability (table S5). The KruskalWallis analysis suggests that these differences in circularity are statistically significant (χ2 = 552.05, df = 5, P value < 2.2 × 10−16), although the Bonferroni correction makes it again necessary to qualify this statement (table S6), with no differences between—for example—the beads found in 10.049 and those recovered in UE 209 and 90. Fig. 3. Montelirio beads in situ. (A) excavation process of individual 343. (B) detail of the threaded beads recorded underneath individual Ue 343 (belonging to attire Ue 344). (C) detail of the threaded beads on attire Ue 344 next to the bones of individual 343. (D) detail of the ivory acorn integrated in the fabric of attire Ue 344, belonging to individual Ue 343. Photographs: (A) by A. Acedo García; [(B) to (d)] by d.W.W. A threedimensional (3d) model of individual eU343 is available at https://skfb.ly/o7oWO. 3d model by M.d.- G. with photographs taken by d.W.W. Downloaded from https://www.science.org on March 29, 2025 Sanjuán et al., Sci. Adv. 11, eadp1917 (2025) 29 January 2025 Science AdvAnceS | ReSeARch ARticle 5 of 14 Chronometric modeling A major goal of this study was to establish the chronology of the beaded attires. In light of the organic character of most beads, radiocarbon was deemed suitable. The specific aims were (i) to obtain an overall model of all beaded attires to establish their age range and a comparison of; (ii) the making of beads and the death of the group of people in the grave; (iii) the time of death of specific individuals and the making of the attires they wore when they were buried; (iv) the individual attires between them; (v) the use of Montelirio and the closely associated Structure 10.042–10.049 (grave of The Ivory Lady), particularly to test the hypothesis (3) that the beads found in the latter (alongside other grave goods) were deposited at the time of construction/use of Montelirio, sometime after the burial of The Ivory Lady. As explained in the Materials and Methods, 24 radiocarbon determinations were successfully obtained. Four determinations were excluded from the Bayesian models: OxAX253532 (human bone), which dates an individual buried in the Montelirio corridor in the early centuries of the fifth millennium BC, long before Montelirio was built, Ua40801 and Ua40802 (human bone) from the Small Chamber, which was badly disturbed in Roman times, and OxA32200, a date on charred material (unidentified roundwood twig) from the Montelirio main corridor, which yielded a much later age (Iron Age). To start with, note that the model based on human bone dates that showed the best overall agreement (Amodel: 95), suggested that the Montelirio tholos was first used (perhaps built) in 2875–2700 2σ cal BC and continued to be used until 2805–2635 2σ cal BC, being in use for a period of 1 to 200 years (95% probability) or 1 to 100 years (68% probability) (2). First, a Bayesian model incorporating all 24 dates on shell beads revealed a start boundary in 3400–2995 2σ cal BC or 3250–3060 1σ cal BC and an end boundary set in 2595–2345 2σ cal BC or 2540–2420 1σ cal BC (fig. S4A), which are compatible with the model based on human bone. Of course, the large number of shells needed to manufacture the whole Montelirio bead assemblage must have involved a wideranging catchment along the neighboring coasts, probably involving shells of varying ages. Next, Bayesian models were calculated for the beaded attires for which radiocarbon determinations were available (fig. S4B and table S8). For Individual UE102, an adult female aged 25 to 34 years at the time of death and wearing a fullbody beaded tunic, two models were calculated. The first, onephased model incorporated all dates available for this individual (three on bone and five on shell beads) and was not robust, with a verisimilitude index below 60%. Removing date OxA41319, which is older, the model was still not robust. The onephase model was only robust if both the oldest shell (OxA41319) and bone (CNA585) dates were removed. A second, twophase model departs from the assumption that the shells for the beads were collected before the woman’s death and includes two sequences, one for the shell bead dates and another for the bone dates. This model was not sufficiently robust; however, if the oldest dates on shell (OxA41319) and bone (CNA585) were removed, then the resulting model is robust. Together, the first model suggests that it could reasonably be assumed that the shells were collected at or near the time of burial, while the second model suggests a collection of the shells beforehand. However, given the short time difference between both phases in Fig. 4. Cleaning and weighing of the beads in the Sevilla Archaeology Museum in July–August 2019. (A) Plastic containers containing the beads. (B) Manual cleaning of the beads after sieving. (C) example of manually cleaned beads. (D) Weighing of the beads. Photographs: l.G.S. Downloaded from https://www.science.org on March 29, 2025 Sanjuán et al., Sci. Adv. 11, eadp1917 (2025) 29 January 2025 Science AdvAnceS | ReSeARch ARticle 6 of 14 the second model, as is shown in fig. S5A, the time difference between the collection of the shells, the making of the beads, and the death of the woman was quite short. For individual UE103, a female aged 25 to 29 years, two models were also calculated. A onephase model including all dates (one on shell and three on bone) was not statistically robust, as the shell bead date is discordant with the oldest date on bone. A second model assuming two phases also turned out not to be robust, even removing date OxA28245, the oldest of the tree bone dates. Therefore, the bead appears to be posterior to the death of individual UE103. Individual UE343, a female aged 24 to 32 years at the time of death, must have been a very special person. Not only she wore what seemingly was a fullbody beaded tunic, but also she was also placed at a prominent location in the tomb, right in front of the unbakedclay stela that presided over the center of the LC, on the path of the narrow projection of sunlight that came from outside on the summer solstice, and with both her arms raised above her shoulders and head, in a gesture frequently described as “oranti” in the literature on European late prehistory (24). Her bones yielded the lowest mercury levels in the Montelirio LC (5). A first, onephase model incorporating all dates available for this woman (four on shell bead and one on bone) provided a statistically robust result. A second, twophase model excluding the oldest shell bead date (fig. S5B) was also statistically robust. Consequently, similar to individual UE102, the shells were apparently collected shortly before or at the time of burial. Regarding Structure 10.042–10.049, which basically is believed to have been originally built some two or three generations before Montelirio (2) and later revisited when Montelirio was built and/or in use, an interesting finding is that the two dates from the motherofpearl beads that decorated the rock crystal dagger deposited above The Ivory Lady are statistically identical. First, a singlephase model that included the three dates on human bone and two on shell bead from the first chamber (Structure 10.042) and the two dates on the beads of said dagger from the second chamber (Structure 10.049) turned out not to be statistically robust. Next, a second model was built excluding date CNA1303 (on human bone) from the first chamber, older than the rest (which are basically coeval). This model turned out to be statistically robust (Amodel: 84); because they share a large proportion of the probability range, these determinations must date events occurring very closely in time. Fig. 5. Highresolution photographs of selected beads. (A) Bead Ue94, inv89, ind102, M020 (marine shell). (B) Bead ind101102, Ue9495, M01 (marine shell). (C) Bead Ue374 (cloth) and M051 (marine shell). (D) Ue94, inv90, ind102, and M055 (marine shell). (E) Bead Ue105, inv3, ind105, and M079 (marine shell). (F) Bead lRtii, e1, and Ue53 (chloritoid schist). the photos are focusstacked composites taken with a canon R5 with MPe 65mm f2.8 macro lens set at f5.6. the same ×3 magnification was maintained for every photograph. lighting was achieved with two led panels, and both camera and lights set to 5200 K to ensure consistent color representation. camera was mounted on a computercontrolled, motorized macro rail (cognisys Stackshot 3X), and raw format images were taken at 0.2mm intervals resulting in a stack of 25 to 35 images for each bead. these were then combined using heliconSoft “helicon Focus” software, method B (depth map setting with radius = 8 and smoothing = 4; these parameters established by experimentation), to produce the resulting final images. Scale was established by photographing physical scales with identical settings and then adding the scale graphic to each image using Photoshop, at which time minor additional corrections of the background were also undertaken to remove dust, etc. Photographs by d.W.W. Fig. 6. Highresolution photograph of beads from the upper level of Structure 10.049 (UE 535, above The Ivory Lady), attached to the rock crystal dagger. the photograph is a focusstacked composite made following the same technique (and with the same equipment) described in Fig. 5. Photograph by d.W.W. Downloaded from https://www.science.org on March 29, 2025 Sanjuán et al., Sci. Adv. 11, eadp1917 (2025) 29 January 2025 Science AdvAnceS | ReSeARch ARticle 7 of 14 Third, considering that the two dates of the rock crystal dagger beads are basically coeval with the individual dated by CNA1291, a third, twophase model was built, assuming a first phase in which the individual dated by CNA1303, buried in Structure 10.042, was earlier than both the individual dated by CNA1291 (in the same chamber) and the rock crystal dagger deposited in the upper level of second chamber (Structure 10.049). This model is very robust statistically (Amodel: 121), which suggest that the reuse of Structure 10.042–10.049 at the time of the construction and/or use of Montelirio involved both the deposition of highend artifacts (such as the rock crystal dagger) and the deposition of human bodies (or bones). In this hypothesis, the temporal limits of Structure 10.042–10.049 would be as follows: First phase, start boundary set in 3150–2775 2σ cal BC or 2955–2880 1σ cal BC and end boundary set in 2925–2760 2σ cal BC or 2910–2855 1σ cal BC; second phase start boundary set in 2900– 2710 2σ cal BC or 2885–2780 1σ cal BC and end boundary in 2870– 2700 2σ cal BC or 2880–2610 1σ cal BC. This fully confirms the complex pattern of use/reuse between Structure 10.042–10.049 and the Montelirio tholos, which had been suggested in previous studies (3), and reveals the close cultural, social, and perhaps kinbased connection between the people buried in both tombs. Phytoliths Two samples of soil solidified inside the perforations of two different beads were taken for phytolith and microarcheological analysis. These beads came from the Montelirio LC and had not been submitted to in situ consolidation. Sample “MONT1 DJ09 UE 355 N°B Ind. I” (from the sediments surrounding the beads) yielded a single, smallsized phytolith fragment (<60 μm), probably of the long cell type associated with grasses (Poaceae). It was affected by siliceous dissolution (Fig. 9A). However, under the microscope, this sample revealed a series of microfiber fragments of birefringent optical behavior, in some cases superimposed, in what look like remains of a mesh, most probably connected with the fabric used to make the attires (Fig. 9B). These fragments are not siliceous, as they do show anisotropic bodies and an internal layered structure, similar to those present in certain plants with cellulose composition. Sample “MONT1 UE 94, N°B7” yielded several examples of globular/spherical phytoliths with echinate ornamentation that are typical, among others, of palmaceae (Arecaceae), probably belonging to Chamaerops humilis (shrublike clumping palm), a species known in Iberia since at least the Miocene [(25) and Fig. 9C]. Similar phytoliths are also produced by palmaceae of the genus Phoenix (26), with known difficulty in identifying genera using only this type of phytoliths (27). Although little evidence exists for either in Iberian archeological contexts dating to late prehistory, C. humilis would appear as the most likely candidate, perhaps in connection with the fabric of the attires. Fragments of what appears to be a mesh of fibers forming a fabric were also found in this sample, with sizes always smaller than 200 μm in length and 70 μm in width (Fig. 9D). The shape and texture of these fiber fragments are not unlike those found in clothing made in Linum usitatissimum (flax) used in traditional rural Galicia (Spain), samples of which were observed under the microscope for this study. Flax is known to have been in use since the Upper Paleolithic (28) and is attested in Early Bronze Age Iberia (29,30). Experimental work Experimental work on the production of shell beads was undertaken, following four steps, as described in Materials and Methods. Section Fig. 7. Details of the beads showing the different directions of the ribs. (A) left: view of the inner side of the bead, right: view of the outer side showing the ornamentation. [(A) and B] Straight and subparallel ribs, corresponding to Pectinidae. (C and D) Slightly curved and parallel ribs, corresponding to cardiidae. design: F.M.G. and S.R.- c. Downloaded from https://www.science.org on March 29, 2025 Sanjuán et al., Sci. Adv. 11, eadp1917 (2025) 29 January 2025 Science AdvAnceS | ReSeARch ARticle 8 of 14 S3 documents time invested in the various tasks preparing one bead for each shell species. Making one Cardiidae shell bead was more timeconsuming (91 min on average) than making a Pectinidae one (19 min on average), as the former are thicker and have more marked ribs than the latter. Using the average of the time needed to make both types of beads (55 min), and the quantification of the whole assemblage described above, 270,000 beads, it would have taken 247,500 hours to make all beads found in Montelirio. However, it must be assumed that the crafts people who made the beads in the Copper Age were far more skilled at the job than modern archeologists. Therefore, if the average time is divided by five, then the resulting average time to make one bead would be 11 min, which would result in 49,500 hours for the production of the whole assemblage. Next, an estimation was made of the volume of shells required to make all the beads. On the basis of the area of an average preform (as shown in fig. S6A2), which is 7.26 cm2, and considering the average area of a P. maximus shell (109.71 cm2), it was calculated that each shell would provide a maximum of 15 preforms. Assuming each preform yielded only one bead (which is reasonable, based on our experimental work), the total number of shells needed to produce the whole assemblage (in the lower range of the estimation, that is to say, 270,000 beads) would be 18,000. This estimate errs on the side of caution, as shells of Cardiidae are smaller and therefore a higher number of them would have been needed. Since, on average, a P. maximus shell valve weighs 44.6 g, this would represent 802 kg of marine shell involved in the production of the entire assemblage of beads. In summary, 10 persons working 8 hours a day would have taken 206 days (nearly 7 months) to produce the whole assemblage using in the process a little less than a metric ton of marine shell. Evidently, the labor value of the beaded attires was high. DISCUSSION The multidisciplinary approach deployed for this study has produced evidence for interpreting the remarkable Montelirio bead assemblage. Beads are a widespread and pervasive element of material culture produced by Homo sapiens. Excellent indicators of technology, social organisation, exchange patterns, and even beliefs, beads are a topic of research in their own right (31). Accordingly, the archeological and anthropological literature on these elements is quite vast. An annotated bibliography produced by the “Society of Bead Researchers” in 2016 and then updated in 2024 lists over 400 pages of references on this topic (32,33). Examples of the extensive bead production and use abound since the Upper Paleolithic in both the New and Old Worlds. However, in quantitative terms, it is difficult to find a singleburial collection of Fig. 8. Scanning electron microscope images of lithic beads. (A) chloritoid schist, (B) white micachlorite phyllite, (C) shale, and (D) limestone. design: t.d.R. Downloaded from https://www.science.org on March 29, 2025 Sanjuán et al., Sci. Adv. 11, eadp1917 (2025) 29 January 2025 Science AdvAnceS | ReSeARch ARticle 9 of 14 discoidal beads of Montelirio’s magnitude, worldwide. At the site of Sunghir, in Russia, dating to c. 32,000 BC, grave 1 contained the remains of an adult male almost completely covered in c. 3000 mammoth ivory beads (as well as other personal ornaments), which are believed to have been sewn onto clothing (34). At Mal’ta, in Siberia, a child burial dating to between 23,000 and 19,000 uncal years before present was found in connection with a rich necklace of 120 bone beads associated with fragments of a tiara made from mammoth ivory, a large ovalshaped pendant, a round bone plaque with a zigzag pattern, and a figurine of a flying bird (35). At the Neolithic village of Ba′ja (7400–6800 BC), in Jordan, an 8yearold child was found accompanied with more than 2500 beads that formed a complex ornament placed around its neck and chest (36). In Iberia, discoidal perforated beads, often made on marine shell, such as P. maximus, are documented since the Early Neolithic (c. 5400 BC) (37) and appear commonly in burials of the Copper Age (c. 3200–2300 BC) (38) and Early Bronze Age (c. 2300–1550 BC) (39). Two thousand years ago, the Chumash people of the Santa Cruz Island (California) produced millions of shell beads that were used as currency and circulated over hundreds of miles across North America, as far as Oregon, the Great Basin, and the Southwest (40–42). Among prestate societies, published Paleolithic and Neolithic examples, such as those of Sunghir, Mal’ta, and Ba′ja involved several hundred or, at most, a few thousand beads. In North America, where bead making was substantial among the Chumash of California and in Cahokia, in the Mississippi region, during the first millennium AD, the bestknown examples, including the “Beaded Burial” (or Mound 72) at Cahokia (containing the remains of a man and a woman), reach up to c. 30,000 beads at most (41,43,44). Of course, beads were widely used among early state societies of Mesopotamia and Egypt, in some cases involving spectacular attires, such as that of Queen Puabi of Ur’s (Mesopotamia) burial dress (or shroud), dated to c. 2500–2600 BC (45). However, in most cases, these attires were made of fewer tubular beads of precious stones such a lapis lazuli, carnelian, or agate and not massproduced discoidal beads such as those found in Montelirio. The calculations presented here suggest that the whole Montelirio bead assemblage could have been made in around 7 months by 10 persons working fulltime 8 hours a day. Obviously, any increase in the amount of labor deployed in its production would have reduced that time. Then, it does not appear as if the communities living at or around Valencina in the early centuries of the third millennium cal BC suffered from a shortage of labor. Together, the tasks involved in the processing of almost one metric ton of shells, which obviously had to be found on the nearby shores, collected, transported, and stored, added to the amount of work involved in the manufacturing of the beads. The detailed chronometric models presented here suggest that the beads were manufactured near the time of death of the women who wore them. This raises the question of the temporality of use of Montelirio. The bestfitting chronometric model, based on human bone, does not exclude a relatively long period of use over a few decades (2). In that scenario, the beads might have reasonably been produced during that period of time. However, the radiocarbon model also does not exclude the possibility of a single burial event, with the women all dying at the same time, in which case the implications for the production would have been different. In that scenario, the attires may have been produced over a much shorter period of time. The chronology of the beads themselves supports both possibilities: They do not appear to have been “old” (for example, heirlooms) by the time they were deposited in the grave. However, at the same time, one of the dated beads is later than the person next to whom it was found, which runs counter to the “single burial event” hypothesis. Either of those two scenarios is consistent with the growing evidence suggesting a rather “explosive” surge of early social complexity at Valencina in the period c. 2900–2650 BC. This is reflected in the deployment of a broad range of highly specialized crafts, involving sumptuous artifacts made of gold, ivory, rock crystal, amber, flint, mylonite, and marine shell, by the local elites. In light of the findings described above, sumptuary textiles must have played a part in the display and exhibition of authority and power and as part of the paraphernalia associated to the emerging elites. All dress is an expression of identity (46). For those sharing common cultural codes, attires can visually (and rapidly) inform about gender, age, and social standing, thus classifying people into groups. Specifically, dress is a crucial element in the performativity of gender (47,48). The social value of dresses may have been even higher in early complex prestate societies, with acquired, and not ascribed, social statuses. In that context, weaving appears as an expanding technological and economic activity in Copper Age Iberia (49,50). Thus, the Montelirio beaded attires may well have been expressions of the collective identity of the people (mostly women) buried in it, including age, gender, and social standing (46). Therefore, the Montelirio beaded attires must be seen as another materialization of the process of identity construction Fig. 9. Microarchaeological and phytolith analysis. (A and B) Sample “MOnt1 dJ09 Ue 355 n°B ind. i”. (C and D) Sample “MOnt1 Ue 94, n° B7”. Magnification: [(A) and (c)] ×600; [(B) and (d)] ×400. (A) Fragment of elongate phytolith, perhaps with echinate ornamentation in origin, proposed to be grasses (Poaceae) and belonging to the contextual sediment. (B) Microfragments of fibers proposed to be remains of L. usitatissimum (flax). (c) Phytolith of palmae (Arecaceae), here in apparent anatomical connection and probably belonging to C. humilis, with fusiform carbonated silt (23 μm × 18 μm) and clays microaggregates. (d) Microfragments of fibers proposed to be remains of L. usitatissimum (flax). images: J.A.A.v. Downloaded from https://www.science.org on March 29, 2025