RESEARCH ARTICLE Analysis of precious metals from the tomb of the “Lady of Cao” by X‐ray microtomography and digital radiography Soraia R. Azeredo 1 | Roberto Cesareo 2 | Régulo F. Jordan 3 | Arabel Fernandez 3 | Giovanni E. Gigante 2 | Angel Bustamante 4 | Ricardo T. Lopes 1 1 COPPE, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil 2 Istituto diMatematica e Fisica, Universita' di Sassari, Sassari, Italy 3 Museo Señora de Cao and Fundacion Wiese, Trujillo, Peru 4 Fisica del Estado Solido, Universidad Nacional Mayor de San Marcos, Lima, Peru Correspondence Soraia R. Azeredo, COPPE, Universidade Federal do Rio de Janeiro; Centro de Tecnologia (CT), Rio de Janeiro, Brazil. Email: soraia@lin.ufrj.br Funding information Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro; Conselho Nacional de Desenvolvimento Científico e Tecnológico, Grant/Award Number: 154293/2016‐4 Investigative analyses of metallic objects from the tomb of a queen of the Moche civilization, who lived around 100 to 300 AD in the northern coast of current Peru, known as Lady of Cao, have been carried out by researchers in the last 4 years using various destructive techniques. Many of these objects found inside the tomb are jewelry produced using silver, gilded copper, copper, and gold sheets. The application of X‐ray microtomography (μCT) and X‐ray digital radiography techniques using a portable system had the objective of obtaining more information on the structures of the objects studied, and thus to obtain some evidences about the production methods used by Moche arti- sans. In this way, radiographic and microtomographic images were acquired, and qualitative and quantitative analyses were performed. A fish in gold and a nose decoration in silver were examined by radiographic methods, whereas a silver earring and a gold needle were analyzed by μCT. Important informa- tion on the structure of these objects were gained. 1 | INTRODUCTION The Moche was a civilization that flourished approxi- mately in the period 100–600 AD on the north coast of present‐day Peru and produced painted pottery, monu- ments, and gold–silver ornaments. The Moche are known as sophisticated metal smiths, both in terms of their tech- nology and in the beauty of their jewels. The Moche met- alworking ability was impressively demonstrated when Walter Alva and coworkers discovered in 1987 the “Tumbas Reales de Sipán” [1,2] and, more recently, when Regulo Franco Jordan discovered the tomb of the “Lady of Cao” in 2005 [3–7] . Spectacular gold and silver funerary ornaments were excavated and are now exposed in the Museum “Tumbas Reales de Sipán” in Lambayeque, close to Chiclayo and in the site Museum of Cao, about 60 km north to Trujillo. Analyses of metal artifacts from the Moche tomb Lady of Cao (Figure 1) have been carried out in recent years by energy dispersive X‐ray fluorescence, transmission of monoenergetic X‐rays, electron microscopy, and digital radiography [8–10] . In this paper, several artifacts were studied using X‐ray digital radiography and computed microtomography (μCT). These methods are nondestructive and based on the differences in the attenuation of X‐rays by different materials. Their importance is growing in archeological area for structural/investigative analysis of artifacts [11– 14] , especially when the digital version with a plat panel is used [15–21] . Received: 1 October 2018 Revised: 18 December 2018 Accepted: 3 January 2019 DOI: 10.1002/xrs.3013 X‐Ray Spectrometry. 2019;1–6. © 2019 John Wiley & Sons, Ltd. wileyonlinelibrary.com/journal/xrs 1