Vesuvianite from Somma-Vesuvius volcano (southern Italy): chemical, X-ray diffraction and single-crystal polarized FTIR investigations
- Author(s)
- Giuseppina Balassone, Dominik Talla, Anton Beran, Angela Mormone, Angela Altomare, Anna Moliterni, Nicola Mondillo, Michele Saviano, Carmela Petti
- Abstract
A suite of twelve vesuviante samples from skarn and syenitc ejecta from the Somma-Vesuvius volcanic complex was studied by means of a combination of energy dispersivespectrometry (EDS), inductively-coupled plasma-mass spectrometry (ICP-MS), powder andsingle-crystal X-ray diffraction, polarized radiation Fourier-transform infrared (FTIR) singlecrystalmicro-spectrometry. Some thermo-gravimetric analyses (TGA) were also performed.Vesuvianite crystals are dark brown to honey yellow-brown, rarely reddish-brown, and up to2 centimetres in dimension. Their major elements (SiO2, Al2O3, CaO and MgO) compositionis rather constant, while Fe2O3, MnO and TiO2 are slightly more variable. Light elements (B,Be and Li), Y, REE and actinides (Th, U) have been detected in all samples in minor to traceamounts, together with V, Zn, Zr, Sn, Co, Ga, Nb, Ta, Hf, Pb and Bi. Among the volatiles,fluorine is prevailing (in a range 1.41-2.25 wt. %). Water and chlorine are always observed,in the range 0.67-1.03 wt. % and 0.01-0.05 wt. %, respectively. Single-crystal X-ray diffractionanalyses of vesuvianite gave P4/nnc as the most probable space group. Cell parameters varyfrom 15.542 Å up to 15.576 Å for a and 11.800 Å up to 11.827 Å for c. Polarized FTIR spectraof the OH fundamental measured parallel to the c-axis are dominated by absorption bands at3638, 3567, 3452 and 3200 cm-1, with two additional bands centred at 3590 and 3117 cm-1.All bands show strong pleochroism with maximum absorption parallel to the c-axis and weakabsorption components perpendicular to c. The spectra measured perpendicular to the c-axisare also dominated by the 3567, 3590 and 3638 cm-1 band group. OH amounts have beencalculated using the total integrated absorption coefficient derived from the fitted spectra.
- Organisation(s)
- Department of Mineralogy and Crystallography
- External organisation(s)
- Università degli studi di Napoli Federico II, Istituto Nazionale di Fisica Nucleare (INFN), Roma, Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", CNR
- Journal
- Periodico di Mineralogia
- Volume
- 80
- Pages
- 369-384
- No. of pages
- 16
- ISSN
- 0369-8963
- Publication date
- 2011
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105116 Mineralogy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/86a98dd8-2be2-4437-ad77-2bb4d04c580c