SEM, EDS, and FTIR Examination of Archaeological Mineralized Plant Fibers

Abstract

The chemical and p ysical structures of archaeological mineralized plant fibers are studied using energy x-ray dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and FTIR microspectrometry, and compared with two contemporary bast fibers. The outer surfaces of the fibers and the inner surfaces of the lumens are heavily en crusted with copper. Fresh-fractured cross sections of the mineralized fibers display small bead-like copper inclusions embedded within the fiber structure. In comparison with modern bast fibers, the mineralized fibers display an absence of hemicellulosic absorption bands (1740 cm-1), greater intensity, and sharper and well-defined indi vidual absorption bands in the 1200-1500 cm-1 region rather than a broad overlap of absorption found in the modern fibers. The mineralized fibers also display a lower crystallinity ratio ( 1372/2900 cm-1) than those of their counterparts.