The mineralization of fibres in burial environments

Abstract

The mineralization of cellulosic and proteinaceous fibres has been simulated using oxygenated aqueous solutions. In addition to chemical analysis of the fibres and the aqueous media, the reactions of the fibres were studied by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) microscopy and reflectance UV spectroscopic techniques. Both positive and negative casting mechanisms were observed. The mechanism peculiar to a given solution depends on kinetic factors relating to the mineral product formation; in particular the relative mineralization rates of the basic copper(II) chloride trimorphs are considered. Mineralization of fibres occurs within days of deposition in the burial environment and acts to preserve the fibre morphology. These experiments rationalize both the occurrence and the comparative rarity of mineralized organic fibres from archaeological deposits. Traces of the organic component have been shown to survive long-term burial and, in appropriate circumstances, permit their identification even in highly mineralized samples.