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Il recente crollo di un blocco di piperno da una cornice del campanile di Sant'Agostino Maggiore (o alla Zecca) in Napoli, annesso alla basilica omonima, ha dato avvio a riflessioni dal carattere interdisciplinare relative alle problematiche di stabilità e conservazione dei materiali costituenti tale architettura, importante riferimento visivo nel centro storico di Napoli. Realizzato entro il 1618 e già consolidato con catene metalliche nel 1732, il campanile barocco presenta una struttura in Tufo Giallo Napoletano rivestita all’esterno da una cortina in laterizio e da elementi decorati in piperno, lava e marmo che, con il loro accostamento, generano un raffinato esito cromatico. Fenomeni di distacco di blocchi lapidei, come quello verificatosi di recente, non sono nuovi per questa struttura, come dimostra il distacco già verificatosi nel 1889. Quest’ultimo condusse ad un complesso restauro effettuato tra il 1914 e il 1919, documentato nel dettaglio attraverso fonti archivistiche. L’intervento, individuando le cause dei dissesti nella scadente messa in opera dei materiali di rivestimento e nell'erosione delle malte, condusse all'introduzione di cerchiature e tiranti metallici per il consolidamento strutturale del campanile e di grappe in rame per il fissaggio dei rivestimenti. Mirando a salvaguardare soprattutto l'aspetto esteriore della fabbrica, gli interventi furono in parte nascosti con tasselli lapidei o celati tra i blocchi dei rivestimenti e delle murature. Seguendo una prassi in via di diffusione, inoltre, il cemento fu ampiamente impiegato nel fissaggio delle parti distaccate con l’obiettivo di migliorare l’aderenza al nucleo tufaceo. Sulla scorta di un’approfondita conoscenza e localizzazione puntuale dei restauri condotti sul campanile nei secoli passati, il contributo si propone di delineare, primariamente, un dettagliato quadro dei materiali e delle tecniche costruttive adottate nel cantiere di inizio Seicento e, quindi, di mettere in evidenza le problematiche connesse all’interazione tra parti ‘originarie’ e quanto apposto nel corso dei restauri successivi: l'ossidazione delle parti metalliche, in particolare, appare oggi molto evidente, unitamente ad un più diffuso degrado dei materiali. Coniugare il rispetto dell’autenticità della fabbrica e, di conseguenza, delle soluzioni adottate nel tempo per il suo restauro e salvaguardare, nel presente, il campanile a fronte di fattori di rischio ricorrenti costituisce il nodo – teorico prima ancora che tecnico – intorno a cui si sviluppano le riflessioni contenute nello scritto con un apporto multidisciplinare, al fine di fornire un contributo culturalmente fondato al progetto di conservazione da attuarsi.

In Europe the use of zeolite-rich tuffs as additives in animal feeding is well established and ratified by legislation. Quality checks on batches are mandatory to determine the undesirable elements such as lead that, among the heavy metals, plays a primary role for its devastating effects on the life quality of living beings. The present study aimed at determining the total and leached Pb for different samples of Campanian zeolite-rich tuffs related to the most relevant volcanic eruptions (Campanian Ignimbrite and Neapolitan Yellow Tuff). Other samples deriving from other Italian and extra-european exploitation sites were used for comparative tests. The research demonstrated that lead occurrence is linked to the specific paragenesis of the investigated rocks whereas the leached Pb largely depends on the type of zeolite and its amount. It was also established that the use of Campanian zeolite-rich tuffs as additives in animal feeding can be tolerated as these materials are well comparable to analogous products from the minerogenetic point of view such as the clinoptilolite of volcanic origin..

This study deals with the characterization of ancient seawater concretes from the Roman harbour of Soli-Pompeiopolis, 1st century B.C., at Mersin in Turkey, drilled by the ROMACONS (Roman Maritime Concrete Study) team in 2009. This research activity was performed in collaboration with the Laboratories Department of CTG Italcementi Group and the Earth Sciences Department of the University "Federico II" of Naples. Results confirmed that the Roman engineers extensively used coarse tuff aggregate, lime hydrated in seawater, and pozzolanic volcanic fine sand, the so-called pulvis puteolanus of Vitruvius's treatise De Architectura (1st century B.C.). The typical mineralogical association of phillipsite > chabazite > analcime, in particular points out the provenance for the tuff aggregate from the Yellow Neapolitan Tuff (NYT) formation, which is connected to the Campi Flegrei volcanic activity, dated back to 15.000 years ago. As far as the fine pozzolanic sand, of which just some scoria relics have been observed, can be ascribed to the same formation, or, probably, to the pozzolan stricto sensu pyroclastic flow from the Campi Flegrei area, as well. EDS microanalyses of different phillipsite crystals showed that the content of major alkaline and alkaline-earth metals was very close to those of phillipsite crystals from NYT, with K higher than Na and Ca, as previously reported in the literature. This fact clearly attests that zeolites were not involved in cation exchange processes within the seawater, despite of their long time curing approximately two thousand years - in the marine environment.

Cusano limestone is an ornamental stone cropping out in the central-southern Italy and extensively used for the historical buildings construction with structural and architectonic purposes. Artificial weathering experiments were conducted on Cusano limestones coming from La Valle and Cana le quarries, located in the Benevento and Frosinone provinces (Italy) respectively. Rock specimens were subjected to standardized freeze-thaw cycles and salt crystallization tests; to this aim non-destructive and destructive tests were carried out including open porosity and p-wave velocity measurements and mechanical testing. Finally the main deterioration morphologies affecting the Cusano limestone were identified through a detailed study on the facades of the bell tower of the Santa Chiara monastery in Naples.

The purpose of this research is to provide a new mixture of Campanian zeolitized tuffs for solving two specific problems in the production of white wines: the protein and tartaric stability. In fact, a very frequent cause of turbidity and formation of organic deposits in white wines is the occurrence of thermolabile and thermostable proteins colloidal suspensions which precipitate in time, especially in summertime and during the storage and transport. Normally, to mitigate this risk wine producers use organic and inorganic stabilizers and clarifiers. The best known treatment, recognized also by the International Organisation of Vine and Wine (OIV) foresees the use of bentonite with a montmorillonite content not lower than 80%. The present paper aims at evaluating the use of two high zeolite grade Italian volcanoclastites such as the Neapolitan Yellow Tuff (NYT) and the Yellow Facies of the Campanian Ignimbrite (YFCI), in the treatment of three peculiar white wines of the Campanian region (Southern Italy): Falanghina, Fiano di Avellino and Greco di Tufo. Granulates were produced starting from tuff blocks as provided by quarries. Some grain size fractions have been prepared to investigate the zeolite content (phillipsite + chabazite + analcime) by X-ray diffraction (XRD). A 2-5 mm grain size fraction was chosen for NYT and a 5-10 mm for YFCI. Three Campanian monocultivar white wines were used for the test: the Falanghina 2006 vintage, the Fiano di Avellino DOCG 2007 vintage, and the Greco di Tufo DOCG 2008 vintage. 48 samples with mixture of the zeolitized tuffs, 1 sample with mixture of a synthetic zeolite A and 1 sample with mixture of a commercial sodium activated bentonite were prepared. ICP-OES analysis for the determination of ECEC, Ion Chromatography (IC) analyses for the determination of some major cations and Turbidimetric tests for the definition of the protein stabilization process before and after treatments were also carried out. It was evidenced that high zeolitized tuff/wine ratios enable the protein stabilization whereas a significant decrease of potassium ion after the treatment with a zeolite-rich powder improves the tartaric stability, a serious problem in all the wine productions. The results of these tests refer to a laboratory scale research. A transfer of the experiment to a pilot plant scale is in progress.

Low-cost, naturally-occurring mixtures of feldspar and zeolite occurring in epiclastic rocks are promising substitutes for conventional quartz-feldspathic fluxes in ceramic bodies, since their fusibility and low hardness are expected to improve both grinding and sintering. Three epiclastic outcrops, with a different zeolite-to-feldspar ratio, were characterized (XRPD, fusibility) and tested in porcelain stoneware bodies; their behaviour during processing was appraised and compared with that of a reference. The addition of an epiclastic rock (20 wt.%), replacing rhyolite and aplite fluxes, brought about some significant advantages, mainly represented by better grindability, lower firing temperature with improved mechanical strength and lower porosity. Disadvantages concern increased slip viscosity, worse powder compressibility, resulting in larger firing shrinkage, and a darker colour of the tiles due to relatively high amounts of iron oxide.

The combination of erythromycin and zinc in the topical antibiotic therapy of acne has been proved useful to reduce the development of antibiotic-resistant strains. An Italian zeolite-rich rock, containing 66 wt.% of clinoptilolite, has been used to prepare an active carrier for erythromycin. The zeolite has been conditioned in zinc form by a set of cation exchange processes, then erythromycin has been adsorbed onto the micronized rock by vacuum drying. After 6 month ageing, almost 95% of the loaded drug was found, indicating good stability of the Zn-carrier-erythromycin system. Minimum inhibitory concentration (M.I.C.) assay on Propionibacterium acnes showed that the process of adsorption of erythromycin does not affect its antimicrobial activity. Both drug and zinc release were evaluated from the carrier powder: the erythromycin release was more than 80% in the first hour and independent on hydrodynamic conditions (United States Pharmacopoeia dissolution apparatus or Franz cell). The release of zinc was fast, and more dependent on the hydrodynamic conditions. The influence of formulating the carrier by dispersion in two anhydrous bases, an absorption petrolatum base (HP) and a water soluble polyethylenglycol base (PEG), was evaluated. In both cases erythromycin and zinc showed a release quantitatively similar to that of the powder, although the release rate was slightly lower from the more hydrophobic HP base.