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Pozzolanic reaction of volcanic ash with hydrated lime is thought to dominate the cementing fabric and durability of 2000-year-old Roman harbor concrete. Pliny the Elder, however, in first century CE emphasized rock-like cementitious processes involving volcanic ash (pulvis) "that as soon as it comes into contact with the waves of the sea and is submerged becomes a single stone mass (fierem unum lapidem), impregnable to the waves and every day stronger" (Naturalis Historia 35.166). Pozzolanic crystallization of Al-tobermorite, a rare, hydrothermal, calcium-silicate-hydrate mineral with cation exchange capabilities, has been previously recognized in relict lime clasts of the concrete. Synchrotron-based X-ray microdiffraction maps of cementitious microstructures in Baianus Sinus and Portus Neronis submarine breakwaters and a Portus Cosanus subaerial pier now reveal that Al-tobermorite also occurs in the leached perimeters of feldspar fragments, zeolitized pumice vesicles, and in situ phillipsite fabrics in relict pores. Production of alkaline pore fluids through dissolution-precipitation, cation-exchange and/or carbonation reactions with Campi Flegrei ash components, similar to processes in altered trachytic and basaltic tuffs, created multiple pathways to post-pozzolanic phillipsite and Al-tobermorite crystallization at ambient seawater and surface temperatures. Long-term chemical resilience of the concrete evidently relied on water-rock interactions, as Pliny the Elder inferred. Raman spectroscopic analyses of Baianus Sinus Al-tobermorite in diverse microstructural environments indicate a cross-linked structure with Al3+ substitution for Si4+ in Q3 tetrahedral sites, and suggest coupled [Al3++Na+] substitution and potential for cation exchange. The mineral fabrics provide a geoarchaeological prototype for developing cementitious processes through low-temperature rock-fluid interactions, subsequent to an initial phase of reaction with lime that defines the activity of natural pozzolans. These processes have relevance to carbonation reactions in storage reservoirs for CO2 in pyroclastic rocks, production of alkali-activated mineral cements in maritime concretes, and regenerative cementitious resilience in waste encapsulations using natural volcanic pozzolans.

The Real Museo Mineralogico of the University of Naples Federico II was established in 1801 by Ferdinando IV of Bourbon and his queen, Maria Carolina. Their aim was to create a centre for minerals research and education. The museum at present preserves over 50,000 objects, mainly minerals, but also books, teaching models and instruments. The last of these form a little-known collection of considerable scientific and historical value. Historical studies of the instruments collection are based on extensive archival research conducted on documents and ancient catalogues of the museum and the Archivio di Stato in Naples. This study describes the main instruments, detailing their date of acquisition, typology and use. Its goal is to provide a testimony to the contribution of the Real Museo Mineralogico to the development of the science of mineralogy in Naples, and at the same time to extend, by means of new data (suppliers, acquisition methods, price), the catalogue of the instruments collection. [ABSTRACT FROM AUTHOR]

This paper reports a detailed study on some relevant portions of the main façades of Caserta Royal Palace (Reggia di Caserta), one of the most important Italian monuments, comparable for its impressive architecture to the Royal Palace of Versailles in France and considered the largest royal palace in the world by volume. The research was focused on the weathering pathologies affecting the stone surfaces that, in the last decades, suffered several detachments of fragments from the coatings and from other architectural elements such as string courses, eaves, and capitals. A preliminary characterization of the materials of the façades and an evaluation of the relative weathering pathologies provided the information required for appropriate restoration and securing of these portions of the building. In particular, an innovative evaluation procedure which draws on techniques typical of the earth sciences allowed the proposal of a 'risk attitude' applied to discrete portions of the geomaterials used in the built heritage which is based on the influence of different factors leading to weakening of the stone and to the final detachment of rock fragments. Such a large and complete set of information should be carefully considered by the project planners to adopt the required steps for a suitable risk mitigation and for securing the site during restoration. [ABSTRACT FROM AUTHOR]

The crystal structure, crystal chemistry, and low-temperature structural evolution of natural thomsonite from Terzigno, Somma-Vesuvins volcanic complex, Naples Province, Italy, have been investigated by means of in situ single-crystal X-ray diffraction, electron microprobe analysis in the wavelength dispersive mode, and Raman spectroscopy. Six structure refinements have been obtained at different temperatures: 295.5,248.0, 198.0, 148.0, 98.0, and 296.0 K (after the low-T experiments). The reflection conditions and the structure refinements prove that the crystal of thomsonite here investigated is orthorhombic with a = 13.0809(3), b = 13.0597(3), c = 6.6051(1) [Angstrom], V= 1128.37(14) [[Angstrom].sup.3], and space group Pbmn, which differs from thomsonite from different localities reported in previous studies (with a ~ 13.1, b ~ 13.06, c ~ 13.2 [Angstrom], and space group Pncn). The refined bond distances suggest that the Si/Al-distribution in the tetrahedral framework is fully 'disordered,' giving rise to the halving of the c axis relative to that found in 'ordered' thomsonites. The extra-framework population consists of: (1) one site about 50% occupied by Ca (labeled as 'Ca'); (2) one site occupied by Na (~70%) and Ca (~30%) (labeled as 'Na'); and (3) three water molecule sites ('WI,' 'W2,' 'W3'). The structure refinements allowed the location of all the proton sites, and the hydrogen-bonding scheme in the structure is provided. The low-temperature refinements show no significant change in the structure within the T-range investigated. The evolution of the unit-cell volume with T exhibits a continuous and linear trend, without any evident thermo-elastic anomaly, with thermal expansion coefficients [[alpha].sub.v] = [V.sup.-1]*[delta]V/[delta]T= 20(2)*[10.sup.-6] [K.sup.-1] (between 98.0 and 295.5 K). A list with the principal Raman active modes is provided and a comparison with the vibrational modes previously found for 'ordered' thomsonite is carried out. Keywords: Zeolite, thomsonite, Somma-Vesuvious, crystal chemistry, low temperature, single-crystal X-ray diffraction, single-crystal Raman spectroscopy DOI: 10.2138/am.2010.3353

The crystal-structure, crystal-chemistry, and low-temperature behavior of a natural phillipsite-Na from the 'Newer Volcanic Suite,' Richmond, Melbourne district, Victoria, Australia [[[K.sub.0.75]([Na.sub.0.88][Ca.sub.0.57).sub.[SIGMA]1.45] [([Al.sub.2.96][Ti.sub.0.01][Si.sub.5.07).sub.[SIGMA]8.04][O.sub.16] x 6.2[H.sub.2]O (Z = 2) a = 9.9238(6), b = 14.3145(5), c = 8.7416(5) [Angstrom], [beta] = 124.920(9)[degrees], and V = 1018.20(9) [[Angstrom].sup.3], space group P[2.sub.1]/]m], have been investigated by means of in situ single-crystal X-ray diffraction, thermogravimetric analysis, and electron microprobe analysis in the wavelength dispersive mode. Two accurate structural refinements have been obtained on the basis of single- crystal X-ray diffraction data collected at 298 and 100 K, with: [R.sub.1] [(F).sub.298K] = 0.035, 3678 unique reflections with [F.sub.o] > 4[sigma]([F.sub.o]) and 195 parameters, and [R.sub.1] [(F).sub.298K] = 0.035, 3855 unique reflections, [F.sub.o] > 4[sigma]([F.sub.o]) and 195 parameters. In both refinements, the residuals in the final difference Fourier maps are Keywords: Zeolite, phillipsite, crystal chemistry, low temperature, single-crystal X-ray diffraction