Geochemical evidence for the use of lead in Prehispanic metallurgy at El Purgatorio, Casma Valley, Peru

Abstract

Portable X-ray fluorescence analyses of metal artifacts from El Purgatorio, the capital city of the Casma state, show a significant presence of lead in several artifacts. Compositional analysis indicates that late Prehistoric peoples were using either intentional selection of lead-bearing ores, intentional mixing of lead with other metals to form alloys during the manufacturing process, or perhaps using both techniques as part of their metallurgical technology. These findings confirm the use of copper-lead alloys by pre-Inca cultures, an advance that had previously lacked much support, and establish the Casma state as one of the cultures contributing to Andean metallurgical traditions.

Chemical composition of small fragments of metals from Castillo de Huarmey (Peru): Chemical analysis in the micro‐area using FE‐SEM‐EDS, FE‐EMPA and XRD

“…The obtained results coincide with the results of other researchers (e.g., Lechtman 1991, 1996; Lechtman and Klein 1999; Petersen and Brooks 2010; Vogel et al . 2015; Giersz and Rizzuto 2018). They also indicate that both sulphide and oxide ores were used in the production of Cu alloys.…”

“…2014; Vogel et al . 2015). Based on the research of these artefacts, they evaluated the melting techniques, the ores used and the obtained metal alloys.…”

“…Until now, research on the production of metals originating from pre-Inca times focused mainly on the analysis of artefacts from the border areas of southern Peru, western Bolivia and northern Chile (e.g., Maldonado et al 2012;Macfarlane and Lechtman 2014;Jennings et al 2015) and from north-west and central Peru (e.g., Lechtman 1976Lechtman , 1981Lechtman , 1984Lechtman et al 1982;Shimada 1996;Schorsch 1998;Cesareo et al 2011bCesareo et al , 2013Shimada and Craig 2013;Shugar et al 2014;Vogel et al 2015). Based on the research of these artefacts, they evaluated the melting techniques, the ores used and the obtained metal alloys.…”

Modern coin debasement discovered by combined portable X‐ray fluorescence and atomic absorption spectroscopy in Peruvian cent coins (1950–1965)

“…XRF spectra were analyzed using the software Artax Spectra 7.4.0 from Bruker Nano GmbH. Instead of a least squares fit, this software uses Bayesian deconvolution of the spectra to minimize the peak overlap effects and then extracts the net intensities of the elements . The background is calculated by the software using the bremsstrahlung radiation of the X‐ray tube.…”

Isotopic composition of lead white pigments on qeros: implications for the chronology and production of Andean ritual drinking vessels during the colonial era

“…In general, the term "lead white" refers to pigments that have a lead carbonate base, which is usually either cerussite (PbCO 3 ), hydrocerussite ((PbCO 3 ) 2 (OH) 2 ), or a mixture of the two [31]. Although Inka and pre-Inka groups are known to have used lead metal and lead-copper alloys [32,33] there is no evidence that they ever made or used lead-based pigments. Instead, white pigments found on prehispanic Andean wall paintings, ceramics, and sculptures generally contain gypsum, calcite, or clays [34][35][36][37].…”