A newly developed spectrometer for energy-dispersive micro X-ray fluorescence spectrometry has been designed for the demands of archaeometry. ArtTAX combines the advantages of non-destructive and sensitive multi-elemental analysis at sub-mm resolution with the possibility of working outside the laboratory. The spectrometer consists of an air-cooled, low-power molybdenum tube, new generation polycapillary X-ray optics, a silicon drift detector without the need for liquid-nitrogen cooling, a CCD camera, and three light diodes for sample positioning. The motor-driven measurement head is fixed on a x,y,z-flexible tripod support which can be assembled and dismantled within minutes. The spot size of the primary X-ray beam was determined to be 94 microm for the Cu(Kalpha) energy, the detection limits are in a range of a few tens of microg g(-1) for the medium energy-range in glass. Additional open helium purging in the excitation and detection paths enables the determination of elements down to sodium, thus avoiding vacuum conditions or a size-limiting sample chamber. A selection of qualitative and quantitative results on pigment, metal, glass, and enamel analyses are presented to show the potential of ArtTAX in the field of art and archaeology.

Micro x‐ray fluorescence analyses were undertaken on individual glass particles of different compositions for selected particle sizes between 50 µm and ≥1 mm. These experiments revealed a complex behaviour in the fluorescence spectra; this behaviour is influenced by the glass matrix, topology, particle volume, energy range and polycapillary properties and cannot be corrected by simple approaches. Net fluorescence intensities and reproducibility measured with two different polycapillaries (40 and 60 µm) were evaluated for six element lines between 1 and 10 keV and compared with the same standard glasses provided as ideal specimens (i.e. with flat, polished surface and of ‘infinite’ thickness). A standardless quantification using the fundamental parameter model gave a reasonable accuracy for particle sizes ≥1 mm (ca 15% relative standard deviations for the main elements) without further sample preparation. The feasibility of principal components analysis for a fast identification of compositional types using the measurement data of individual particles was demonstrated. Copyright © 2002 John Wiley & Sons, Ltd.

A novel sampling technique for the analysis of glass is described, which involves the removal of minute particles from an object with a diamond-coated ®le, followed by energy-dispersive X-ray analysis in the scanning electron microscope (SEM/EDXA). The particles are ®xed to adhesive carbon discs and carbon coated without grinding or polishing. Mean compositions are determined for 10 arbitrarily selected particles above a minimum grain size of 150 mm and normalized to totals of 100%. Tests were carried out on two standard soda±lime±silica glasses of well-characterized composition, using two ®les of different grade. The analyses showed good agreement with the accepted values of all elements. Although the precision is somewhat reduced, this highly portable and quasi non-destructive microsampling procedure provides almost the same information as that gained from samples embedded and polished in the normal way. Its application is thought to be especially useful for the investigation of intact glass objects and ceramic glazes.

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