In Val d’Ala (Western Alps in Piedmont, Italy), the most interesting rocks for mineralogical research are represented by rodingite (rich in mineralized veins and fractures) associated with serpentinite in the eclogitized oceanic crust of Piedmont Zone, south of Gran Paradiso Massif. Among the vein-filling minerals, vesuvianite is well appreciated for its potential as gem-quality materials, even though it has never been characterized in detail. This study provides a gemological characterization of eleven vesuvianite crystals from different localities of the Val d’Ala. The refractive index (1.717–1.708) and density (1.705–1.709) values of our vesuvianite are in the range of those in the literature. Scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) established that the samples are pretty compositionally homogeneous in terms of major elements, while trace and rare earth elements (REE) contents are more variable. All REE patterns are characterized by pronounced positive Eu anomalies. The variations in color (from olive green to dark green with chocolate (reddish-brown color shades and polychrome bands) are due to the relevant presence of Fe and, to a lesser extent, Ti and Cr. The X-ray powder diffraction (XRPD) analyses and SEM/EDS quantitative study indicate that the other phases associated with vesuvianite are represented by diopside, garnet, clinochlore.

The Burano Formation in Val Secchia in the province of Reggio Emilia is rich in black or very dark quartz. The crystals are often pitted by scars, rarely shiny, often opaque, rarely translucent, and about 3 cm long. However, they have a beautiful color and are generally euhedral and bi-terminate with simple habitus and well developed faces—for these characteristics, they are very sought after by collectors. Micro-Raman analyses showed the quartz contains abundant inclusions of anhydrite and graphite. The inclusions of anhydrite are responsible for the chromatic inhomogeneity, while the black color is linked to the presence of disordered graphite inclusions. LA-ICP-MS analyses did not show a significant presence of chromophore elements. Black quartz formed in the original evaporite deposits of gypsum, which, due to diagenesis and the increase in temperature during deep tectonic burial conditions, lost water of crystallization and subsequently transformed into anhydrite. After the formation of quartz crystals, the Burano Formation was exhumated and rehydrated, resulting in gypsification at conditions close to the surface. The black quartzes of the Burano Formation represent an appreciable gemological material for the development of local craftsmanship, even if the difficulties in reaching the deposit limit their marketing.

In this work a rare and attractive blue diopside present in Sissone valley in the Western Alps was investigated through different methodologies: geological survey; standard gemological methods; X-Ray Powder Diffraction; SEM observations; Raman spectrometry; EMP analyses of major elements; and LA-ICP-MS analyses for minor and trace elements. The host rock of investigated gems is represented by a Mg-calcite bearing marble, belonging to the Suretta nappe and composed of blue diopside, lizardite, phlogopite, forsterite, Ca-Mg-amphibole, and thomsonite; the rock was metamorphosed by the intrusion of Masino-Bregaglia pluton. The diopside is generally found in the core of veins in contact with green–blue tremolite and, more externally, with green–yellowish lizardite. The diopside samples show opaque diaphaneity, are inert to long and short-waves UV radiation, and their specific density varies between 3.24 and 3.30 g/cm³ while medium refraction between 1.680–1.683. The diopside shows a polycrystalline texture with interstitial Mg-calcite which acts as binder. The characteristic blue–turquoise color is mainly determined by traces of V and subordinately of Fe, Mn, Cr and Ti. The contents of V and Ti show a good positive correlation. The minerals associated with diopside in the lenticular veins also show enrichments in V. The blue diopside of the Sissone valley could certainly present a good commercial value, but unfortunately it is difficult to reach the outcrop sites.

This work investigates the gemological properties of the datolite from the famous field of Campotrera near Reggio Emilia in Italy, for a possible commercial use in the market. This mineral occurs in widespread multi-centimeter veins, together with calcite and prehnite, within polygenic breccias in basaltic ophiolites. The most common form for this datolite is the double wedge with a prism (110) and a pinacoid (001). The gems obtained are mixed or carré cut, colorless or salmon pink, transparent, with a vitreous luster and weight between 1 to 5 carats. They have high brilliance, transparency and birefringence, glassy luster, absence of cleavage. The major chromophore is probably Fe, which occurs as inclusion of hematite and ilmenite. Raman investigations highlighted different fluid inclusions. The primary are randomly distributed or, in some cases, follow the growth zones, while the secondary form aligned tracks along the microcracks. Fluid inclusions can be biphasic and made up by liquid + gas (L + G), generally >10 mm in size, and more rarely, monophasic, composed only by liquid (L) generally <10 mm. The gems extracted from the rough sample are very valuable but their delicacy requires attention in the cutting and preparation of the jewels.

The General Assembly of the United Nations declared 2014 the International Year of Crystallography, after 100 years from the awarding of the first Nobel Prize for the discovery of X-ray diffraction by crystals. On this occasion, the Department of Chemical and Geological Sciences of Modena and Reggio Emilia University (Italy)and its Museum “Gemma 1786”, organized an exhibition named Cristalli ai raggi X (Modena, 24 Jan.-29 Mar. 2015). The initiative involved the cooperation of many public and private partners and the active participation of twenty schools of different types and levels. An innovative aspect was the planned participation of highschool students to the fifty collateral events organized during the exhibition. The main purpose of Cristalli ai raggi X was to introduce non-specialists to the world of crystals and their properties, and to show how crystallography plays a role in the development of scientific disciplines. The display ended with the appreciation of 9,000 visitors and a hundred of guided tours for regional and extra-regional schools.The activity developed by the Manini Middle School of Vezzano sul Crostolo (Reggio Emilia province) involved 27 students of 13thyear-old. During an exhibition event opened to the public, they presented a study on the features of gypsum and the extraction history of the land where they come from and where, in the past, the gypsum was an important economic resource.