SEM technology for the analysis of tiny calcified remains from a pre-Hispanic burial from El Hierro (Canary Islands)

Abstract

Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) enables the determination of the composition and structure of tiny calcified remains occasionally recovered during burial excavations. To deepen the practical application of this technique, we performed SEM/EDX analysis on three different tiny mineralized, roughly rounded structures with a diameter of less than 5 mm recovered from a pre-Hispanic collective funerary cave from El Hierro (Canary Islands) and a mineral spherulite of similar size and outer aspect. After SEM imaging and spectroscopic analysis, we conclude that the three samples represent a sesamoid bone, a kidney stone, and a possible case of sialolithiasis. In contrast, the spherulite is a mineral formation composed of calcium carbonate. Our data confirm SEM analysis's usefulness in identifying small, mineralized remains recovered during burial excavations and its contribution to studying past populations. However, we are aware that taphonomic changes may alter, at least partially, the structure, and/or elemental composition of archaeological samples, obscuring differential diagnosis.