Both Raman and infrared spectroscopy have been used to characterise the three phase-related minerals -dreyerite (tetragonal BiVO 4 ), pucherite (orthorhombic BiVO 4 ) and clinobisvanite (monoclinicBiVO 4 ) -and a comparison of the spectra is made with that of the minerals namibite (Cu(BiO 2 )VO 4 (OH)), schumacherite (Bi 3 O(OH)(VO 4 ) 2 ) and pottsite (PbBiH(VO 4 ) 2 ·2H 2 O). Pucherite, clinobisvanite and namibite are characterised by VO 4 stretching vibrations at 872, 824 and 846 cm −1 . The Raman spectrum of dreyerite shows complexity in the 750 to 950 cm −1 region with two intense bands at 836 and 790 cm −1 assigned to the symmetric and antisymmetric VO 4 modes. The minerals schumacherite and pottsite are characterised by bands at 846 and 874 cm −1 . In both the infrared and Raman, spectra bands are observed in the 1000-1100 cm −1 region which are attributed to the antisymmetric stretching modes. The Raman spectra of the low wavenumber region are complex. Bands are identified in the 328 to 370 cm −1 region and in the 404 to 498 cm −1 region and are assigned to the n 2 and n 4 bending modes. The minerals namibite and schumacherite are characterised by intense bands at 3514 and 3589 cm −1 assigned to the symmetric stretching vibrations of the OH units. Importantly, Raman spectroscopy enables new insights into the chemistry of these bismuth vanadate minerals. Raman spectroscopy enables the identification of the bismuth vanadate minerals in mineral matrices where paragenetic relationships exist between the minerals.

The phosphate minerals hannayite, newberyite and struvite have been studied by Raman spectroscopy using a thermal stage. Hannayite and newberyite are characterised by an intense band at around 980 cm -1 assigned to the ν 1 symmetric stretching vibration of the HPO 4 units. In contrast the symmetric stretching mode is observed at 942 cm -1 for struvite. The Raman spectra are characterised by multiple ν 3 antisymmetric stretching bands and ν 2 and ν 4 bending modes indicating strong distortion of the HPO 4 and PO 4 units. Hannayite and newberyite are defined by bands at 3382 and 3350 cm -1 attributed to HOPO 3 vibrations and hannayite and struvite by bands at 2990, 2973 and 2874 assigned to NH 4 + bands. Raman spectroscopy has proven most useful for the analysis of these 'cave' minerals where complex paragenetic relationships exist between the minerals.

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Raman microscopy was used to confirm the presence of wyartite, CaU 5+ (UO 2 ) 2 (CO 3 )O 4 (OH)(H 2 O) 7 , in the presence of rabejacite, (Ca(UO 2 ) 4 (SO 4 ) 2 (OH) 5 ·6H 2 O), obtained from the Ranger Mine, Northern Territory, Australia. This occurrence is unusual in that it means that a uranyl carbonate has been formed under acidic conditions. Wyartite is a mineral known for the occurrence of pentavalent U 5+ . A band is observed at 818 cm −1 in the Raman spectrum of wyartite assigned to the n 2 symmetric bending mode of the (CO 3 ) 2− units. The presence of carbonate is confirmed by the n 1 stretching vibration at 1071 cm −1 and the n 3 stretching vibrations at 1445 and 1345 cm −1 . Two bands are observed at 853 and 837 cm −1 and are assigned to the n 1 stretching modes of the UO 2 units. Raman spectroscopy allows the partial band separation of the n 2 (CO 3 ) 2− and n 1 modes of UO 2 . The Raman spectrum of rabejacite is characterized by an intense sharp band at 1010 cm −1 assigned to the n 1 stretching mode of (SO 4 ) 2− . Three bands observed at 1086, 1123 and 1175 cm −1 are attributed to the n 3 antisymmetric stretching modes of (SO 4 ) 2− . The mineral rabejacite is also characterized by n 2 bending modes at 457 and 394 cm −1 and n 4 bending modes at 666, 605, 537 and 505 cm −1 . Raman spectroscopy has proven most useful for the detection of wyartite in the presence of other mineral phases.

Advanced analytical techniques have been used to characterize arsenic in taxidermy specimens. Arsenic was examined to aid in discriminating its use as a preservative from that incorporated by ingestion and hence indicate poisoning (in the case of historical figures). The results are relevant to museum curators, occupational and environmental exposure concerns, toxicological and anthropological investigations. Hair samples were obtained from six taxidermy specimens preserved with arsenic in the late 1800s and early 1900s to investigate the arsenic incorporation. The presence of arsenic poses a potential hazard in museum and private collections. For one sample, arsenic was confirmed to be present on the hair with time-of-flight secondary ion mass spectrometry and then measured with neutron activation analysis to comprise 176 microg g(-1). The hair cross section was analysed with synchrotron micro-X-ray fluorescence to investigate the transverse distribution of topically applied arsenic. It was found that the arsenic had significantly penetrated all hair samples. Association with melanin clusters and the medulla was observed. Lead and mercury were also identified in one sample. X-ray absorption near-edge spectroscopy of the As K-edge indicated that an arsenate species predominantly existed in all samples; however, analysis was hindered by very rapid photoreduction of the arsenic. It would be difficult to discriminate arsenic consumption from topically applied arsenic based on the physical transverse distribution. Longitudinal distributions and chemical speciation may still allow differentiation.