We tested several sample pre-treatment protocols for the study of oxygen isotope ratios in the phosphate phase of mammalian enamel of ten different fossil samples. We investigated the effect of different pre-treatment methods and the duration of the hydrogen fluoride treatment on enamel samples from skeletal phosphate with known δ18O values. The samples had been measured previously, so we could compare the ratios measured in our laboratory with the previous values to choose the best chemical preparation procedure. Four pre-soaking methods and two different time intervals of 2 mol dm−3 hydrogen fluoride treatment were compared during our experiments. In our experimental conditions, the distilled water wash and the 6 h of soaking in hydrogen fluoride gave the closest results to the expected δ-values. The steps of the tested preparation processes were repeated at least three times on each sample, so the reproducibility of the process could be also investigated.
Impact material, especially magnetizable tiny grains (spherules, globules and platelets) of Barringer Meteor Crater (Arizona) was studied by combined nuclear analytical techniques. The samples were analyzed first by micro-proton-induced X-ray emission (PIXE) and deuteron-induced gamma-ray emission (DIGE) methods. In this way it was possible to determine the distribution of elements down to carbon. Using micro-synchrotron radiation X-ray fluorescence technique (SRXRF) we could determine medium and high atomic number trace elements such as the platinum-group metals. Our methodological developments made it possible for the first time to carry out quantitative analysis for more than 40 elements, providing new perspectives for the interpretation of the impact materials. Various compositions of the findings around the Barringer Crater were compared to analytical data of similar objects found in Carpathian Basin to elucidate their origin. This paper summarizes the more important results obtained by using ion beam microanalytical techniques.