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It is crucial to understand the structural origins of macroscopic properties in silicate glasses for their high-tech applications. An example of such an application is chemically strengthened boroaluminosilicate glasses that are exposed to an ion exchange process during which alkali ions (e.g. Na+) are replaced by larger (e.g. K+) ions. Despite the empirically thorough understanding of this exchange process, much less is known about the fundamental physics of the process. Since Fe atoms are a suitable probe for monitoring chemical stress-induced changes in the local structure in the chemically strengthened glasses, a set of chemically strengthened boroaluminosilicate glasses containing 1 mol% Fe2O3 are here studied using depth-resolved confocal X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy. Information on the Fe oxidation state, coordination number, and bond distance as a function of the sample depth and glass composition is obtained. These new insights on chemical stress-induced changes will aid in the further development and improvement of such damage-resistant glasses.

Because of its major contributions to the world economy and cultural heritage, Chinese porcelain and its technology can be considered as very important. In this research, the applicability of Raman spectroscopy and X-Ray Fluorescence (XRF) spectroscopy to study the pigments of the ruan-cai colour palette of Chinese porcelain dating from the 18th century was evaluated. Next to the investigations based on stylistic analysis, the use of other analysis techniques is important to obtain complementary information. Raman spectroscopy and XRF spectroscopy are two non-invasive, analytical techniques proven to be useful for the determination of the nature and composition of pigments used to decorate ceramics. As a result, analytical analysis allows us to retrieve more information about the production of Chinese porcelain. Based on visual inspection of the decoration, the objects could be divided into two groups and to evaluate the use of the combined analytical approach, all groups and subgroups were sampled. Before Raman and XRF analyses, the samples were cut, embedded and polished, in order to be able to measure the transversal section of the samples. In this way, each layer of the porcelain samples could be analysed separately. The results show that the blue colour is cobalt-aluminium oxide, in red zones haematite (α-Fe2O3) is present and the green area contains a mixture of CuO in a lead-rich basis and a solid solution of malachite (Cu2CO3(OH)2). The opaque yellow and white colours were identified as lead tin yellow type II (PbSn1−xSixO3, where x ∼ 0.25) and a lead arsenate, respectively.

The capabilities and limitations of nanosecond laser ablation ICP-mass spectrometry for bulk and spatially resolved (elemental mapping) analysis of iron meteorites were assessed. The quantitative data obtained were compared to those obtained i. via multi-element solution ICP-MS (after digestion) relying on external calibration and, ii. high-accuracy determination of selected platinum group elements using solution ICP-MS after target element isolation using anion exchange chromatography and deploying isotope dilution. Results generated by the different methods described show good agreement. Significant matrix effects were observed to affect the results of the ns-LA-ICP-MS analysis of iron meteorites, making quantification via a matrix-matched standard a prerequisite. Careless use of intensity distribution maps without proper correction for laser-solid coupling efficiency can lead to incorrect interpretation of the element maps. ns-LA-ICP-MS was shown to be suitable for fast and quasi-nondestructive analysis of iron meteorites, not only homogeneous ataxites and hexahedrites, but also more heterogeneous ones, when considering ablated areas of a sufficient size. In the context of elemental mapping using LA-ICP-MS, Pearson's product–moment correlation analysis was demonstrated to be a powerful tool that can provide valuable information on the fractionation of the elements in the parent bodies of meteorites.

The development of a novel and straightforward procedure for the preparation of matrix-matched calibration standards for the quantitative imaging of iron (Fe) in biological tissues by laser ablation (LA)-ICP-MS with on-tissue internal standard addition is described. This simple approach enabled on-tissue addition of Rh as internal standard to samples (with heterogeneous Fe distribution) and calibrants (with homogeneous Fe distribution). This is achieved without altering the original Fe distribution of the sample. Calibration standards were prepared by full horizontal immersion of slides with mounted homogenised sheep brain tissue section into the corresponding solution containing 0.5, 0.75, 1, 5, 10 and 20 mg kg−1 Fe (each also containing 250 µg kg−1 Rh as IS) in pure methanol for 30 minutes (6 immersions, each for 5 minutes). Subsequent air-drying (bench drying at room temperature) for approximately 5 minutes was undertaken in between consecutive immersions, to prevent long-term exposure of the tissue to lipid degradation. Tissue-matched standards were characterised in-house for Fe composition, homogeneity and stability (at storage temperatures of −80 °C, −20 °C, 4 °C and 25 °C for up to 2 months) in order to investigate their suitability as calibrants for quantitative LA-ICP-MS. The homogeneity data suggested that the materials are homogeneous in terms of Fe and Rh distribution with RSDs (n = 30) of 8.3% and 4.7%, respectively. The Fe measurement precision was improved by approximately a factor of 2 when normalising 56Fe intensities to 103Rh intensities; the RSD (n = 30) for 56Fe/103Rh was 3.6%. The produced calibration standards were found to be stable when stored at room temperature for approximately 50 days, suggesting that they can be reused for multiple batches. Using LA coupled to double-focusing sector field ICP-MS in medium resolution mode (m/Δm = 4000), linear calibration over a range of 107 to 1519 mg kg−1 Fe (R2 = 0.99) was achieved with a limit of detection of 1.84 mg kg−1 Fe. Assessment of the accuracy of the method for the quantitative imaging of Fe in tissues was undertaken by comparison of the LA-ICP-MS data with that obtained by micro-XRF; the average Fe concentrations in selected tissue regions obtained by using XRF fell within the window defined by the LA-ICP-MS values and their associated standard deviations.

Synchrotron μ-XRF (X-ray fluorescence analysis), a trace level micro analytical method, allows the quantitative study of the nature and degree of heterogeneity of inorganic trace constituents in reference materials with a homogeneous matrix. In the present study, glass materials of NIST, MPI-DING and USGS containing trace levels of heavy metals are considered. The measurements involve an extensive series of local analyses, performed in identical conditions at different locations on the material. This procedure is employed to measure the degree of micro-heterogeneity of several existing reference materials and to evaluate their suitability for calibration of trace-level micro-analytical methods. For a number of the trace elements present in the various reference materials, a minimum representative mass for homogeneous measurements is calculated.

In this paper, the differences and similarities in chemical composition between facon-de-Venise glass excavated in Antwerp and two types of Venetian glass, both from the sixteenth and seventeenth centuries, are documented. On the basis of typological criteria alone it is not possible to distinguish imported Venetian glass from locally produced glass. For this purpose, the major element composition of Antwerp and Venetian glass was studied with EPXMA (electron probe X-ray microanalysis) and, in a second phase, these objects were also analysed for their trace element content by means of SR-XRF (synchrotron radiation induced X-ray fluorescence analysis) and LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry). The largest group of Antwerp objects has a composition that significantly differs from truly Venetian compositions, pointing to an important local production. However, a few objects were found that have a major composition very similar to Venetian Cristallo and a larger group corresponds to the Venetian Vitrum Blanchum composition. In order to be able to make a more clear distinction between the Antwerp Cristallo and Venetian Cristallo glass types, to verify that indeed the Antwerp and Venetian Vitrum Blanchum compositions are identical and to understand better the causes of the compositional differences among the groups, the concentrations of a number of trace elements, possibly providing clues on the raw materials, were determined.

Samples of petrified wood of different origins were analyzed by the use of the electron microprobe, capillary X-ray fluorescence microprobe, synchrotron capillary X-ray microprobe and optical microscope, applied in a microprobe manner. The main attention was given to the investigation of the ring structure of the petrified wood and the comparison of this with the ring structure of the living trees analyzed by much the same methods. The continuous X-radiation, applied in a microprobe manner, the distribution of the gray-scale representation of the secondary electron intensities and the characteristic X-ray signals, mainly from the light elements, were registered by the use of the electron microprobe method. The X-ray capillary microprobe detected the Rayleigh and Compton signals, scattered from microareas of the samples, and the characteristic X-ray signals, mainly from the heavier elements. In the synchrotron-based capillary microanalytical measurements, one of the most important results was achieved by the microprobe application of scattered synchrotron radiation. The emission and scattering results were supplemented by transmission measurements, where possible. All the methods proved to be complementary in the analysis of such periodic structures as tree rings. Both capillary microprobes were much more efficient in the detection of heavy elements and penetrated deeper than the traditional electron microprobe. Careful analysis of different signals indicated that some samples of petrified wood in the authors' possession, composed of silica of variable density, are the chemical negatives of the primordial living wood. This is the first such observation in the literature. Microdiffraction studies of the samples proved that polycrystalline α-quartz was the main matrix component of all these samples. The elemental analysis of the petrified wood gives important indications about the petrification processes. Comparison of the particular ring structure of the petrified wood with the ring structure of living trees shows great similarities. The widths of rings, density variations and density maxima are easily readable from the microanalysis of petrified wood. These parameters potentially can be exploited for the investigation of the biological, chemical, chronological and climatic information included in the fossilized tissues.

The performance of ellipsoidally shaped lead-glass capillaries for focusing the polychromatic synchrotron beam produced by a bending magnet of the DORIS positron storage ring (Hasylab, Hamburg, Germany) is discussed. The size, intensity and energy distribution of the focused beam produced by such capillaries are compared with those of beams generated by means of straight borosilicate capillaries, indicating that beam sizes ofca. 4 µm at the sample surface can be obtained with a total flux density that is ca. ten times higher than when a collimated beam is employed. Synchrotron radiation with energies up to 60 keV is focused, leaving the original energy distribution of the white synchrotron beam virtually unchanged. The analytical characteristics of the µ-XRF set-up at Beamline L of Hasylab, when equipped with a lead-glass capillary, were investigated by means of NIST SRMs and indicate that interference-free absolute/relative detection limits in the 1–10 fg/0.8–2 ppm range are achievable from 100 µm silicate-type samples for the elements from Mn (Z=25) to Gd (Z=64) using their Kα lines within 1000 s counting time. Elemental yields are situated in the 10–100 counts s–1 per 100 mA per (µg cm–2) range. As illustrations of the type of investigations these highly energetic, micrometre-sized beams make possible, the two-dimensional mapping of the distribution of REEs (rare earth elements) and other heavy elements in geological igneous rock samples and the three-dimensional non-destructive analysis of heavy metals (such as V, Fe, Ni and Mo) in individual fly-ash particles by means of fluorescence microtomography are briefly described.

Synchrotron radiation based confocal micro-XRF was employed to unravel the tissue-specific three-dimensional (3D) distribution of metals down to trace concentration levels in a non-destructive manner within the crustacean Daphnia magna, an ecotoxicological model organism. Next to the analytical characterization of the employed confocal micro-XRF set-up, specific areas of metal accumulation in different cross-sections of interest within the organism were investigated. The use of a fast dynamic (continuous) scanning approach delivered 3D information on major, minor and trace element distributions in specific sub-regions within Daphnia magna. Coupling the obtained elemental information with microscopic morphological data obtained by laboratory absorption microtomography, full 3D element-to-tissue correlation could be derived, allowing a more detailed interpretation of the obtained results with respect to metal accumulation within this model organism.

In the field of environmental toxicology, the study on the effects of the presence of transition metals such as Cu, Ni and Zn on the health of pelagic and benthic invertebrates is an important research topic. Fast dynamic 2D micro-XRF scanning and dynamic XRF micro-CT experiments on D. magna, a frequently used ecotoxicological model organism, allow the quantitative investigation of the accumulation of metals within specific organs with microscopic resolution. K-means clustering allows comparison of the concentrations of the elements of interest between different tissues/organs. Principal component analysis allows most of the significant statistical variations in these large and complex multivariate data sets to be explained. Also, by combining SR-XRF and absorption CT data sets using appropriate software packages, it becomes possible to unravel the tissue-specific 2D/3D distribution of metals in-situ within delicate organic samples on the 3–15 μm resolution level in an essentially non-destructive manner.

A novel polycapillary based confocal X-ray fluorescence (XRF) technique was applied for the first time at the ID18F beamline of the ESRF to obtain directly three-dimensional (3D) compositional information of an inclusion inside a natural diamond sample (KK200). Preliminary analysis of the results on the basis of the trace elements Sr, Y/Zr, and Th suggest three phases, two of which were identified by earlier micro-Raman spectroscopy as larnite (β-Ca2SiO4) and CaSiO3-walstromite, two minerals with significantly different Ca content. In order to support this multiphase model for the investigated inclusion the data set was analysed combining the conventional multivariate method of PCA and K-means clustering procedure after application of instrument specific routines such as spectral evaluation and normalization. Through the knowledge of the full spatial 3D structure of the different phases, it was possible to correct for absorption of the fluorescent radiation in the different phases of the inclusion and the surrounding diamond.