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This study undertook the mineralogical and chemical analysis of anglesite (PbSO4), cerussite (PbCO3), gypsum (CaSO4∙2H2O), langite (Cu4(SO4)(OH)6∙2H2O), malachite (Cu2CO3(OH)2), and posnjakite (Cu4(SO4)(OH)6·H2O) detected for the first time in the abandoned Mastricarro Barite Mine (Catanzaro, Calabria, southern Italy). Geological conditions make this one of the few well-preserved, partly accessible mines in the Calabria region. Numerous mineralogical species, some beautifully crystallized, have been discovered among the alteration products of the sulfides present within the barite veins. The newly identified crystals occur as secondary minerals in the oxidized portions of deposits originally containing lead and copper sulfides; they are widely distributed and are almost always detected as microcrystals. The anglesite, cerussite, gypsum, langite, malachite, and posnjakite crystals were identified and characterized using optical microscopy (OM), micro-Raman spectroscopy (µR), and scanning electron microscopy, combined with energy dispersive spectrometry (SEM/EDS). The new mineral occurrences can be useful for scientific and didactic purposes; further, for langite, malachite, and posnjakite crystals, new Raman bands, which have not been mentioned before in the literature, were identified. [ABSTRACT FROM AUTHOR]

This paper presents the results of the compositional study of 29 samples of mortar from the so-called 'Garum Shop' (I, 12, 8) at Pompeii in Southern Italy. The characterization of the samples yielded information on the raw materials used in the mixtures, the production technology of mortars, and the building phases. It was carried out through polarized optical microscopy, X-ray powder diffraction, X-ray fluorescence, microanalysis energy-dispersive X-ray spectroscopic microanalysis, and image analysis through the JMicroVision software. The resultant data show great compositional homogeneity among the samples, suggesting the presence of a principal construction phase, probably associated with the first phase of the house. Apart from this main construction phase, there are some samples that show differences related either to their different function or to the fact that they come from different construction phases or restoration works. The raw materials used are related to the geology of the area and are fully compatible with the pyroclastic deposits of Vesuvius. [ABSTRACT FROM AUTHOR]

The work shows the results of an archaeometric study performed on fourteen white marble samples from the Roman city of Tauriana (Palmi, Reggio Calabria, Italy), belonging to different architectural elements of the Municipal Museum Complex and artifacts reused in the modern town. Samples were studied by optical microscopy (OM), x-ray powder diffraction (XRPD), and isotope ratio mass spectrometry (IRMS) of 13C and 18O with the aim to identify their provenance. The comparison between the collected data and the historical ones, concerning the ancient quarries of white marble of the Mediterranean area, allowed us to prove that most of the marbles used in the city of Tauriana were from the Apuan Alps Basin (Carrara) and, in few cases, from Minor Asia (Proconnesos, Aphrodisias, Docimium) and Greek (Thasos and Pentelic) quarries. [ABSTRACT FROM AUTHOR]

Hydraulicity is a well-known characteristic of mortars and plasters from the Roman, Late Roman, and Medieval periods, while the use of hydraulic mortars in pre-Columbian Mesoamerica and Central Mexico in particular, has not received equal attention. To address this issue, in this paper, we discuss the problem of hydraulicity and suggest a method to study it in Mesoamerican plasters. To prove the effectiveness of this method, we selected plaster samples from the archaeological site of Teotihuacan (Mexico), the main city of Central Mexico during the Classic period. The characterisation of plaster samples confirmed that, similar to other Teotihuacan plasters, they are made of two layers: the outermost layer (enlucido), composed of a mixture of lime and volcanic glass shards, and the underlying layer locally called firme , consisting of crushed volcanic scoria (tezontle) mixed with a mud-based binder. The compositional characterisation of the plasters confirmed their hydraulicity and the combination of microchemical (energy dispersive spectrometer (EDS) microchemical analysis), microphysical (Vickers microhardness), and petrographic (optical microscopy) measurements demonstrated that it was not the presence of glass shards in the external plaster layer which produced hydraulicity, as we originally thought. Instead, this was due to the reactivity of the tezontle , present in the lower layer. This suggests that the small thickness of the enlucido layer, in addition to save the amount of lime used, increased its performance, promoting chemical reactions with the tezontle in the contact layer and that the glass shards played another role in the mixture, rather than producing hydraulicity. • The compositional characterization of 11 plasters from Teotihuacan was performed. • The approach used allowed to study the hydraulicity of the plasters. • A correlation between hydraulicity and tezontle (volcanic material) was highlighted. • Through p-XRF analysis were identified the pigments used in some plasters. [ABSTRACT FROM AUTHOR]