The Contribution of Transmission Electron Microscopy (TEM) to Understanding Pre‐Columbian Goldwork Technology

Abstract

This paper highlights the contribution of transmission electron microscopy (TEM) when combined with scanning electron microscopy and energy-dispersive X-ray microanalysis (SEM/XEDS) to characterize objects in archaeology. The application of TEM in archaeology is not yet a common tool, but it may provide data that are significant to understanding pre-Columbian gold metallurgy, specifically the gilding and silvering methods. Two gilded rods were studied using a combination of TEM and SEM/XEDS techniques. The objects were found at the Atacames archaeological site, in the Esmeraldas region, Ecuador, which was occupied between AD 750 and 1526 by the Atacames culture. The microchemical and structural results of the inner and the external gilded part of the artefacts support the hypothesis of a gold diffusion to the surface enhanced by chemical treatment with chloride-rich solutions, heating and successive annealing processes. The present study reveals that microstructural investigation by TEM provides useful information with which to investigate the techniques used to modify the chemical surface composition of pre-Columbian artefacts.

Archaeometallurgical investigation of ancient artefacts’ degradation phenomenon

“…Further to this, its impact on the corrosion resistance is expected to be explored using advance characterization technqiues such as FIB SEM, TEM etc. [19][20][21] Although the process of corrosion is known to be described in detail, no information is available about the driving force for the formation of delta-FeOOH. It is elucidated that the delta-FeOOH appeared as the amorphous phase with discontinuity in the layer; however, the presence of P is known to enhance the formation of delta-FeOOH as illustrated by Misawa et al 22 however, delta-FeOOH is found to be enriched with Cu, Cr, etc.…”

X‐ray fluorescence spectroscopy and Monte Carlo simulation for quantitative characterization of Bolivian pre‐Hispanic golden artefacts

“…It was one of the first metals used by humans to express different aspects of their culture, such as ritual, decorative purposes and religious uses [1,2,3] . Moreover, there are important civilization expressions about gold artefacts production technology and how they reflected in the evolution stages of a given civilization [4,5,6] . Gold can be found in the nature in its geological native form, it does not corrode and it has a brilliant colour.…”