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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.

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.

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.