Abstract: A general Monte Carlo program for the simulation of X-ray fluorescence (XRF) spectrometers is presented. The global layout of the program is discussed and the way in which variance reduction techniques have been employed to improve the efficiency of the code is described. For the case of polychromatic excitation in a direct excitation energy-dispersive (ED) XRF instrument, experimentally collected ED-XRF spectra are compared with simulated spectral distributions. Applications of the software in the field of quantitative analysis and thickness estimation of samples of intermediate thickness illustrate the potential of the method.

Abstract: Historical glass, especially non-durable mediaeval glass, can undergo corrosion. This sometimes results in the formation of dark-coloured manganese-rich inclusions or stains that reduce the transparency of the glass. A conservation treatment with reducing or chelating agents may be considered with the aim of improving the transparency. In this paper, high-resolution desktop microcomputed tomography (µCT) is used in combination with element-specific twodimensional imaging methods for in situ monitoring of manganese removal by hydroxylamine hydrochloride from an archaeological stained-glass sample suffering from manganese browning and from artificially corroded model glass samples. µCT also proved itself useful for the study of the (re-)penetration of manganese into the gel layer during artificial corrosion of a model glass.

Abstract: The sensitivity and applicability of the synchrotron radiation induced X-ray microfluorescence (mu-SRXRF) spectrometer at the Hamburg synchrotron laboratory Hasylab for the determination of the distribution of trace concentrations of rare-earth elements (REE) in fossilized bone are discussed and critically compared to those of other trace analytical methods such as instrumental neutron activation analysis (INAA) and LAMP-ICPMS (laser ablation microprobe inductively-coupled plasma mass spectrometry). Measurements were carried out on two bone samples from contrasting terrestrial depositional environments at Olduvai Gorge (Tanzania). Results indicate that the microdistribution of the REE in these biological materials is not homogeneous and that the relative abundance of these elements can provide information on the palaeoenvironment during the fossilization process. The heterogeneous distribution of the REE can be determined in a quantitative and completely non-destructive manner provided the concentrations of individual REE are above 10 mu g/g.