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The Syntesis of zeolites from hydrothermal experiments on Sardinian Tertiary clinoptilolite-bearing ignibrites.
No full text
The Syntesis of zeolites from hydrothermal experiments on Sardinian Tertiary clinoptilolite-bearing ignibrites.
No full textLearning and researching in the museum: the education program of Real Museo Mineralogico, Università di Napoli Federico II
No full textEPMA, SIMS and FTIR investigations on sodalites and haüynes from Somma-Vesuvius volcano (southern Italy). 14th European workshop EMAS, Modern Developments and Applications in Microbeam Analysis
No full textSodalite-group minerals (sodalite, tugtupite and danalite subgroups) commonly occur in
alkaline igneous rocks, and in some hydrothermal and metamorphic rocks. These minerals
present a zeolite-like cubic structure and two structural cavities per unit cell. Cationic and
anionic contents of SSG are of interest for the study of magmatic systems; in particular, their
volatile components can be useful because they can provide key information on the genetic
environment, like degassing dynamics, fluids behaviour during hydrothermal processes and so
on [1-4]. Besides, SSG are very promising in different fields of material science, since their
(ultra)microporous structures show high flexibility and versatility in hosting tetrahedral cations
and variable channels/cavities components. Hence, they can be suitable as advanced materials
and behave as models for many technological and commercial applications [5, 6], for instance
separation processing (i.e. hydrogen from gaseous macromolecules). The present study is
focused on crystal-chemical characterization of cationic and anionic components of SSG
occurring in various igneous to metamorphic rocks and ejecta from the alkaline-potassic
Somma-Vesuvius volcano (southern Italy), as revealed by using combined microbeam
techniques, i.e., EPMA, SIMS and μ-FTIR. Previous studies on sodalite-group minerals by
means of EPMA, Raman, and LA-ICP-MS techniques focussed on halogen- (Cl, Br) and
S-contents [2, 3, 8]. To the authors’ knowledge no studies on volatiles in SSG have been
performed so far by integrated SIMS-FTIR investigations. Compared to bulk analyses, SIMS
and μ-FTIR methods are particularly pivotal to probe trace to ultra-trace contents, speciations
and orientations of an absorber across the samples [1, 7]. Our investigations show that the
studied SSG correspond to sodalite sensu stricto, nosean (sulfatic sodalite) and haüyne. SIMS
measurements on H, F and C (quantified as H2O, F and CO2, respectively) show contents:
0.02 - 5.0 wt% H2O, 0.01 - 0.14 wt% F, and 0.69 - 2.95 wt% CO2. Within the single crystals,
the F and CO2 concentrations are virtually homogeneous, whereas in terms of H2O, samples
can vary from homogenous to strongly heterogeneous. Single-crystal FTIR spectra of SSG can
be grouped into sodalites and sulphatic sodalites/haüynes, according to the occurrence of the
12CO2 absorption at 2340 cm-1 [1, 9]. The absorption due to H2O and/or OH groups occurs as a
very broad band extending from 3700 cm-1 to 3000 cm-1. In all samples FTIR data show the
presence of CO32-. μ-FTIR focal plane array imaging shows a very heterogeneous and
antithetical distribution of CO2 and especially of H2O according to the SIMS data.
[ 1] Bellatreccia F, Della Ventura G, Piccinini M, Cavallo A and Brilli M 2009 Min. Mag.
73 399-413
[ 2] Hettmann K, Wenzel T, Marks M and Markl G 2012 Am. Mineral. 97 1653-1661
[ 3] Hammerli J, Spandler C, Oliver N H S and Rusk B 2014 Metam. Geol. 32 93-112
[ 4] Wang L X, Marks M A W, Keller J and Markl G 2014 Chem. Geol. 380 133-144
[ 5] Ferraris G and Merlino S 2005 Rew. Min., Geoch. MSA 57 448 pp.
[ 6] Riley B J, Pierce D A, Frank S M, Matyáša J and Burns C A 2015 J. Nuclear Mat. 459
313–322
[ 7] Ottolini L and Le Fèvre B 2008 Microchim. Acta 161 329-336
[ 8] Hammerli J, Rusk B, Spandler C, Emsbo P and Oliver N H S 2013 Chem. Geol. 337-
338 75-87
[ 9] Balassone G, Bellatreccia F, Mormone A, Biagioni C, Pasero M, Petti C, Mondillo N and
Fameli G 2012 Mineral. Mag. 76 191-21
Archaeometric study of artefacts from firing places of Longola-Poggiomarino protohystoric settlement site (Naples, Italy).
No full textFluorophlogopite and F-rich phases in limestone clasts from the Campanian Ignimbrite quarried at Fiano (southern Italy): mineralogical, geochemical and volcanological insights.
No full textFluorine-rich metamorphosed xenoliths associated to the distal Campanian Ignimbrite (CI) tephra (Campania region,
southern Italy) have long attracted the interest of the mineralogical community (i.e. Scacchi, 1890; Zambonini, 1919;
Masi & Turi, 1972; Balassone et al., 2002). These rocks derive from the Mesozoic carbonate lithotypes of the
Campanian Apennine, embedded in the pyroclastic flow and presently resting at the bottom of the tuff formations. The
sedimentary protoliths suffered from the action of hot, volatile-rich pyroclastic flow, and consequently were affected by
thermal metamorphism to various degrees. Their peculiarity is the occurrence of F- and Mg-bearing phases, with an
ubiquitous presence of neoformed fluorite. The occurrence at Fiano quarries (the so-called “Tufare”) is the classical
locality for these rock xenoliths. Similar rocks were also found in the CI of the Caserta area, and in the Latium region
(Colli Albani). This research aims both at a crystal chemical study of fluorophlogopite occurring in the Fiano xenoliths,
and at a geochemical and volcanological survey, to constrain the petrogenesis processes related to this rare F-, Mg-rich
assemblage and to CI.
The analysed samples belong to two lithotypes: mica-bearing clasts and variably metamorphosed carbonate blocks.
The former lithotype is represented by abundant fluorite, followed by fluorophogopite, F-rich chondrodite, fluoborite,
diopside and (Fe,Mg)-oxides. Minor to trace contents of calcite, humite, tremolite, and grossular also occur. Carbonate
rocks can show calcite only, or also trace amounts of fluorite. The Fiano micas composition approaches that of the
Vesuvius micas from the 1872 eruption (Balassone et al., 2013). The micas belong to the 1M polytype and have crystal
chemical features typical of fluorophlogopites i.e., low c lattice parameter (~ 10.13 Å), (~ 2.060 Å) and (~ 3.135 Å)
distances. New data on minor to ultratrace elements amounts found in the studied clasts, together with Carbon and
Oxygen isotope data will be reported and interpreted in a petrogenetic and volcanological frame.
Balassone G., Franco E., Mattia C.A., Petti C. & Puliti R. 2002. Re-examination of fluosiderite, an unknown mineral
from southern Italy: equal to fluorine-rich chondrodite. Eur. J. Min., 14, 151-155.
Balassone G., Scordari F., Lacalamita M., Schingaro E., Mormone A., Piochi M., Petti C. & Mondillo N. 2013.
Trioctahedral micas in xenolithic ejecta from recent volcanism of the Somma-Vesuvius (Italy): crystal chemistry and
genetic inferences. Lithos, 160-161, 84-97.
Masi U. & Turi B. 1972. Frazionamento isotopico del carbonio e dell'ossigeno negli inclusi calcarei metamorfosati del
"Tufo grigio campano" Auct. di Fiano (Salerno). Per. Min., 41, 291-310.
Scacchi A. 1890. La regione vulcanica fluorifera della Campania. Mem. R. Com. Geol. It., I, 1-48.
Zambonini F. 1919. Il tufo pipernoide della Campania e i suoi minerali. Mem. Descr. Carta Geol. It., 7, 130 pp
I reperti dell’eruzione vesuviana del 1872 della “Collezione Scacchi” (Real Museo Mineralogico di Napoli)
No full textMineralogical, geochemical and isotopic characterization of the hydrothermal sites at Ischia island (southern Italy).
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