RESEARCH POSTER PRESENTATION DESIGN © 2015 www.PosterPresentations.com The site of Castillo de Huarmey is located in the Ancash region of Peru, approximately 300 km north of Lima and 1 km east from the present-day city of Huarmey (Fig. 1). The site covers an area of 45 ha and is dominated by a monumental palace and royal necropolis built on the summit of a natural rock hill. In 2010 a small Polish-Peruvian team of archaeologists, directed by Miłosz Giersz of the University of Warsaw, Poland, began archaeological research at this pre-Hispanic site. Excavations soon revealed Middle Horizon (600 – 1000 CE) architecture and an extensive funerary complex. In 2012 the first known undisturbed royal mausoleum related to elites of the Wari culture was discovered. The royal tomb contained 58 mummies of Wari female aristocrats, six human sacrifices, and over 1,300 sets of unique artefacts made from silver, gold, copper, semi-precious stones, alabaster, wood and other materials (Giersz 2017). In 2018 a new primary burial context was discovered which contained the preserved remains of a young male individual with an intriguing set of copper alloy objects and metallurgical byproducts such as slag and speiss. It is now hypothesized that this individual may have been a metallurgist, potentially associated with the production of the metallurgical materials excavated from this new tomb and that of the site’s royal mausoleum. INTRODUCTION A total of 52 metallurgical objects excavated from Castillo de Huarmey were analyzed by Branden Rizzuto using energy-dispersive x-ray fluorescence spectrometry (pXRF). These objects consisted of 9 gold and silver ear pieces; 4 spindle whorls and an ingot composed of gold alloys; 4 spindle whorls, a bowl, and a chisel composed of silver alloys; and 4 spindle whorls, 11 pins, 4 tumis,2 tupus, 1 round-end spatula, and 10 tool implements (chisels, axes, knives, and saws) composed of copper and copper alloys (see Fig. 2). All analyses were conducted using a Bruker Tracer III-SD pXRF spectrometer. Measurements were taken in air using a 40 kV voltage, a 10.7 μA current, a 60 second acquisition time, and a filter composed of a 25μm layer of titanium and a 300 μm layer of aluminum. Quantification of Au, Ag, and Cu concentrations in all gold and silver objects was performed using Bruker S1PXRF software and custom calibrations designed by Branden Rizzuto (see Table 1). As an insufficient number of reference standards was available for the creation of a copper-arsenic alloy calibration, the raw results obtained from the analysis of copper and arsenic-copper alloy objects were converted into spectral “counts” using Bruker ARTAX software and Bayesian deconvolution analysis. The same method was used to investigate trace and minor elements in the silver alloys analyzed. SAMPLES AND METHODS Table 1 – Results of the pXRF analyses of a gold alloy reference standard (M.A.C. 10156 AC1761), a 14 kt gold alloy sheet, and a Canadian dime containing 92.5% silver by weight. The results demonstrate that the calibrations are both accurate and precise with regards to the elemental quantification of gold alloys and silver-copper alloys. CONCLUSIONS It is clear from the results of the pXRF analyses that the metallurgical objects excavated from Castillo de Huarmey are standardized to some degree. The gold alloy components of the objects analyzed strongly cluster into two groups (Fig. 6). Results from both the gold alloy and silver alloy components of the ear pieces excavated from the Royal Tomb also demonstrate that they were likely produced as pairs with very similar iconographies, morphologies, and elemental compositions. While the little variation and high silver concentrations of these objects suggest the alloying of gold, silver, and/or copper (or their alloys) in carefully measured ratios, some of these objects could have been directly produced from native gold sources (see Petersen 1970). From the analyses of the copper and copper alloy objects excavated from both the Royal Tomb and the Metallurgist’s Burial , it is clear that there is a strong correlation between object type/form and elemental composition. In addition, strong similarities in elemental concentrations between objects of the same type/form from the two contexts indicate the use of a similar production sequence or technological tradition. The results lend evidence to the hypothesis that the individual interred in the Metallurgist’s Burial may have been associated with metallurgical activities at or in connection with Castillo de Huarmey. Lastly, the four spindle whorls from the Royal Tomb are composed of a copper-arsenic-nickel alloy. While, this alloy is commonly associated with Tiwanaku-style metals and some Wari objects from the South-Central Andes (see Jennings et al. 2015), it’s presence is rare on the North Coast of Peru. REFERENCES Giersz, M. (2017). Castillo de Huarmey. Un centro del imperio Wari en la costa norte del Perú. Lima: Ediciones del Hipocampo. Jennings, J., Velarde, M. I., Mora, F., Álvarez, W. Y. (2015). Wari imperialism, bronze production, and the formation of the Middle Horizon: Complicating the picture. Journal of Anthropological Archaeology, 39, 63-75. Petersen, G. G. (1970). Minería y Metalurgia en el Antiguo Perú. Arqueológicas 12. Lima: Museo Nacional de Antropología y Arqueología. ACKNOWLEDGEMENTS The 2010-2018 field seasons of the Castillo de Huarmey Archaeological Project were supported by grants from the National Science Center of the Republic of Poland (NCN 2970/B/H03/2009/37, NCN 2011/03/D/HS3/01609 and NCN 2014/14/M/HS3/00865), the Ministry of Science and Higher Education of the Republic of Poland (579/N-PERU/2009/0), the National Geographic Society (EC0637-13, GEFNE85-13, GEFNE116-14 and W335-14) and financial support from Compañia Minera Antamina S.A. The present study was supported by a grant from the National Science Center of the Republic of Poland (NCN 2014/14/M/HS3/00865), Compañia Minera Antamina S.A., as well as the Pontifical Catholic University of Peru in Lima, Polish-Peruvian Society for Andean Studies, the Ministry of Culture of the Republic of Peru and the local government of Huarmey. The authors would also like to thank Marcos Martinón-Torres (University of Cambridge) and Susan Stock (Royal Ontario Museum) for granting Branden Rizzuto access to their gold alloy reference standards. Miłosz Giersz 1 Branden Cesare Rizzuto 2 1 Institute of Archaeology, University of Warsaw 2 Department of Anthropology, University of Toronto Pre-Colombian Metallurgy at the Middle Horizon (600 – 1000 CE) Site of Castillo de Huarmey, Huarmey Valley, Peru Sample # Object Cu Au Ag Total M-10943 Ear Piece 0.19 89.70 9.95 99.84 M-10944 Ear Piece 0.18 89.13 10.52 99.83 M-10945 Ear Piece 1.97 68.94 28.21 99.11 M-10946 Hybrid Ear Piece 1.40 71.09 26.99 99.48 M-10948 Hybrid Ear Piece 1.53 70.07 27.70 99.31 M-10949 Ear Piece 0.87 86.91 11.94 99.73 M-10951 Ear Piece 1.08 86.76 11.86 99.71 M-10952 Ear Piece 1.42 73.57 24.96 99.95 M-10953 Ear Piece 1.67 72.62 25.47 99.76 M-10954 Spindle Whorl 2.78 64.80 30.87 98.44 M-10955 Spindle Whorl 2.70 75.49 22.13 100.31 M-10962 Spindle Whorl 4.60 67.03 27.08 98.71 M-10963 Spindle Whorl 5.12 67.67 26.03 98.82 M-10970 Ingot 3.86 69.31 25.96 99.13 GOLD Sample # Object Cu Au Ag Total M-10943 Ear Piece (Cylinder) 2.28 bdl 98.44 100.73 M-10944 Ear Piece (Cylinder) 1.54 bdl 98.92 100.45 M-10946A Hybrid Ear Piece (Cylinder) 0.70 bdl 99.29 99.98 M-10946B Hybrid Ear Piece (Base) 1.20 0.31 98.84 100.35 M-10948A Hybrid Ear Piece (Cylinder) 0.90 bdl 99.15 100.05 M-10948B Hybrid Ear Piece (Base) 0.95 0.13 99.00 100.09 M-10956 Spindle Whorl 1.73 bdl 98.68 100.41 M-10957 Spindle Whorl 3.44 bdl 97.26 100.70 M-10960 Spindle Whorl 1.36 bdl 98.88 100.24 M-10961 Spindle Whorl 1.44 bdl 98.88 100.32 M-10974 Bowl 1.22 bdl 98.83 100.05 M-11016 Chisel 0.87 bdl 99.09 99.96 SILVER Standard Statistic Au Ag Cu Sn Zn Total MEAN 74.96 19.12 5.05 1.13 100.26 SD 0.04 0.03 0.02 0.01 Reference Value 74.70 19.20 5.10 1.03 Relative Accuracy (%) 0.34 0.40 1.00 9.50 MEAN 58.21 8.33 29.46 4.29 100.28 SD 0.01 0.01 0.02 0.01 Reference Value 58.3 8.34 29.19 4.17 Relative Accuracy (%) 0.15 0.13 0.91 2.79 MEAN 93.73 7.07 100.80 SD 0.04 0.01 Reference Value 92.5 7.5 Relative Accuracy (%) 1.33 5.78 CALIBRATION TESTS N/A N/A N/A N/A N/A N/A N/A .925 Silver Canadian Dime N/A 14KT Gold M.A.C. 10156 AC1761 Table 2 – Results of the pXRF analyses of the gold alloy components of the objects excavated from the Royal Tomb at Castillo de Huarmey. Table 3 – Results of the pXRF analyses of the silver and silver alloy components of the objects excavated from the Royal Tomb at Castillo de Huarmey. RESULTS AND ANALYSIS M-10943 M-10945 M-10946 M-10949 Figure 2 – Spindle whorls (top-left), ear pieces (top-right), and a silver bowl and chisel (bottom-left) excavated from the Royal Tomb at Castillo de Huarmey and analyzed using pXRF. Copper and copper alloy objects (bottom-centre) as well as hybrid bone-metal objects (bottom-right) excavated from the Metallurgist’s Burial at Castillo de Huarmey and analyzed using pXRF (all photos by Miłosz Giersz). Figure 3 – Principle Component Analysis (PCA) created from the results of the pXRF analyses of the copper and copper alloy objects excavated from the Royal Tomb and the Metallurgist’s Burial. Photon counts obtained from Bayesian deconvolution analysis for As, Ni, Cu, Pb, and Ag were used. All values were first log normalized. Figure 5 – Principle Component Analysis (PCA) created from the results of the pXRF analyses of the silver and silver alloy objects excavated from the Royal Tomb. Weight concentrations for Ag, Cu, and Au were used. All values were first log normalized. Figure 4 – Principle Component Analysis (PCA) created from the results of the pXRF analyses of the copper and copper alloy objects excavated from both the Royal Tomb and the Metallurgist’s Burial. Photon counts obtained from Bayesian deconvolution analysis for As, Ni, Cu, and Pb were used. All values were first log normalized. Figure 6 – Ternary plot of the gold, silver, and copper concentrations obtained from the pXRF analyses of the hybrid ear pieces (blue), other ear pieces (red), spindle whorls (yellow), and ingot (black) excavated from the Royal Tomb at Castillo de Huarmey. All values were first normalized to 100 wt%. Figure 1 – Geographical location (right) and aerial view (left) of the site of Castillo de Huarmey (photo by Miłosz Giersz; map by Julia Chyla) . M-10954, M-10955, M-10962, M-10963 M-10956, M-10957, M-10960, M-10961 M-10958, M-11001, M-11002, M-11008 M-10974 M-11016 M-52 M-48 M-51 M-50 M-49 M-56 M-53, M-54, M-55