New parameters for the characterization of diagenetic alterations and heat-induced changes of fossil bone mineral using Fourier transform infrared spectrometry

Stable isotope and multi-analytical investigation of Monte da Cegonha: A Late Antiquity population in southern Portugal

“…Diagenetic alterations of archaeological bones present a potential problem for the interpretation of isotopic ratios as a source of information for dietary and mobility reconstructions (Hollund et al, 2013;Lebon et al, 2010). Through FTIR and XRD analyses of bone samples it is possible to screen for diagenetic alterations (differences in bone carbonate and collagen content, and in bone crystallinity) in order to understand the reliability of the isotopic data used for dietary and mobility studies.…”

“…XRD analysis revealed the presence of calcite in 13 samples and the presence of quartz in three samples. The increase of bone porosity, due to the loss of organic matter, subsequently allows interactions between bone components and groundwater, as well as promoting the precipitation of secondary minerals (Lebon et al, 2010), such as calcite. Therefore, FTIR and XRD analysis indicate that the samples have been diagenetically transformed in comparison to fresh bones (IRSF N 3.4 (Beasley et al, 2014;Berna et al, 2004;Salesse et al, 2014), C/P values out of the range 0.23 to 0.34 (Beasley et al, 2014), Am/P values below 0.9 (Salesse et al, 2014) and CI N 0 (Person et al, 1996)).…”

“…Diagenesis is a complex process that involves biological and physico-chemical post-mortem alterations of skeletal material directly exposed to soil environments during burial (Beasley et al, 2014;Hollund et al, 2013;Lebon et al, 2010;Maurer et al, 2011Maurer et al, , 2014. Such processes that affect bone preservation can be caused by microbial attack, temperature, humidity, hydrology, pH, and may lead to partial or complete degradation of organic matter (Beasley et al, 2014;Lebon et al, 2010).…”

“…Changes in crystallinity relevant to the evaluation of diagenesis can be measured by X-ray diffraction (XRD) and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) (Beasley et al, 2014;Berna et al, 2004;Brown and Brown, 2011). FTIR also gives information about the composition and structure of the organic phase (Hollund et al, 2013;Lebon et al, 2010).…”

Informative Potential of Multiscale Observations in Archaeological Biominerals Down to Nanoscale

“…Re-crystallization of biogenic biominerals during the first steps of diagenesis can encapsulate non-collagenous proteins or DNA fragments within crystal aggregates and preserve them to longterm alteration. Uranium uptake in dental, osseous and calcareous material and accumulation of electrons in paramagnetic centres of apatite crystal lattice over geological time can allow obtaining chronological data by Uranium-series and Electron Spin Resonance (ESR) dating methods (used separately or combined) (Grün et al 2010;Falguères et al 2010). However, the main part of diagenetic processes leads to a partial or complete modification of biogenic signal such as elemental or isotopic composition.…”