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The outcomes from the feasibility study on utilization of synchrotron radiation X-ray microtomography (SR-μCT) to investigate the texture and the quantitative mineralogical composition of selected calcium oxalate-based urinary calculi fragments are presented. The comparison of the results obtained by SR-μCT analysis with those derived from current standard analytical approaches is provided. SR-μCT is proved as a potential effective technique for determination of texture, 3D microstructure, and composition of kidney stones.

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The chemistry of recent fish scales (tench, common carp, amur and European perch) and subrecent fish scales (European perch and mostly taxonomically not determined) was studied by means of laser ablation inductively coupled plasma mass spectrometry and electron microprobe from shallow boreholes in the abandoned meander Certak near Uherské Hradiste. A detailed study of subfossil fish confirms extremely rapid changes in the chemical composition of hydroxylapatite during very early diagenetic processes in the first 2 years, which does not change significantly in the bottom of the boreholes about 25 years old. While there is an enormous increase in Na, K, Ba and Sr, Fe and Mn, there is a major decrease in Mg. The fish scales from 70 to 78 cm (6-8 years old) are approaching already the level of francolite-type hydroxylapatite. The high Na content indicates carbonate substitutions for OH or PO 4 group. Consequently, environmental interpretations based on the chemistry of fossil hydroxylapatites require extreme caution. In recent fish scales, the element concentrations reflect not only the position in the trophic pyramid but also a complicated interplay of the diet, physiological processes and environmental contamination.