Ricerc@Sapienza

Manganese oxides are important geomaterials, used in a large number of applications. For instance, as pigments in art works or in the treatment and removal of heavy metals from drinking water. Particularly, ramsdellite [Mn4+O2] and groutellite [(Mn0.54+,Mn0.53+)O1.5(OH)0.5], because of their 2 × 1 frameworks that enable proton diffusion, are very important cathode materials. Manganese oxides commonly occur as crypto-crystalline and very fine mixtures of different Mn-phases, iron oxides, silicates and carbonates. Thus, proper characterization can be a difficult task using XRPD.

The identification of dyes from ancient textiles represents a challenging issue requiring high proficiency and versatility, that must be guided by the principles of non-destructiveness. The complexity of the dye/textile system influences both the choice of sampling and extraction procedures and the analytical methodology. For instance, in order to preserve both the fibre and the original chromophores on it, the extraction procedures commonly used for natural dyes have evolved in last few decades towards increasingly mild conditions.

In the road construction sector, soil treatment is a method for increasing the strength and durability of fine soils that would otherwise be waste: the treatment with lime allows building embankments with clayey soils. However, in-situ and laboratory tests should be carried out to verify the correct addiction of lime during earthworks. This study deals with SEM-EDS analyses in order to identify the most reliable method to prepare specimens and obtain relationship between added quicklime and Calcium content after treatment.

A group of orichalcum Roman coins, from private collections, have been studied for this research. Numismatic examination indicated that they are asses, sestertium and dupondius, minted from Julius Caesar to Nero. Orichalcum is an ancient copper based alloy with a variable percentage of zinc.
The aim of this study was to investigate the process of dezincification from the external layers to the core of the samples. Furthermore, the research was aimed to disclose the real chemical composition of the orichalcum alloy.

This article shows the first pigment identification of the Campana reliefs, Roman architectural earthenware plaques. The Campana reliefs polychromy were investigated by applying a multidisciplinary approach involving non-invasive and micro-destructive techniques to some fragments with traces of colour found on the north-eastern slopes of the Palatine Hill in Rome.

The open rock shelter of Yabelo in Ethiopia hosts diverse Holocene paintings of great cultural importance. The paintings are characterized by the presence of different mineral coatings, whose features have not been studied yet. Our goal was to understand whether different rock samples from the Yabelo paintings collected in close proximity may reveal coatings with different minerology and biology. Thus, elemental analyses combined with microscopic and molecular investigations were performed on two coatings, one whitish (sample 1) and one reddish (sample 2).