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Bottom Ashes from Municipal Solid Waste Incinerators and Waste to Energy plants represent an interesting source of secondary raw materials for many applications, like urban mining and inclusion in concrete, and road pavement. However, Bottom Ashes may contain potentially toxic elements, whose actual toxicity depends essentially on their oxidation state and mineralogical environment. For this reason, a representative sample of bottom ashes from Parma Waste to Energy plant has been selected to investigate the chemical speciation of Cr, Ni, Pb, Co, Zn and Cu by means of complementary techniques: Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy (SEM-EDS), micro X-Ray Fluorescence (µ-XRF) mapping and X-Ray Absorption Near Edge Structure (XANES) measurements by synchrotron radiation. This multi-technique approach allowed to obtain a general image of the mineralogical and chemical environment in which these elements are found. SEM-EDS analyses show the presence of Zn and Pb both in minerals and in glass matrix. Cr has been detected in the form of oxide and in spinel structure (chromite) whereas Co and Cu are found as alloy or metal inclusions. µ-XRF mapping reveals that Cu, Ni and Cr are generally associated to Na, K and Si suggesting their presence in glass matrix. XANES investigations exhibit that Cu has a variable oxidation state that suggesting its presence in the form of oxide, hydroxide, acetate and metal. Zn is mainly found as +II and in a number of different phases (including Zn-carbonates, in agreement with SEM-EDS data). Cr has been found only as +III, with XANES features resembling those of chromite, whereas as +VI was never identified. Ni and Co were found either as metal form and oxides. Pb spectra show a good match with oxides.

The Early Bronze Age ceramic collection found into the caves of La Llana and El Toral III in Asturias (Spain) presents common decoration such as that found in the centre of Cantabrian Spain from the same period, which resembles others found in the Ebro Valley and Atlantic Europe. Therefore, the main objective of this study it is to identify the raw material origin and understand the pottery production process during the Early Bronze Age in the Cantabrian region. A methodological approach based on the chemical and mineralogical analysis of vessels and experimentally fired clay samples collected all over the centre of this region was developed. Furthermore, the post‐depositional processes affecting the sherds' composition was evaluated by employing the rare earth elements as markers. The results showed that the studied assemblage has important similarities with the raw materials of the surrounding area, which supports the hypothesis of a regional mobility. [ABSTRACT FROM AUTHOR]

Serpentinized peridotite samples—considered nowadays as deposited waste at the magnesite mine of Gerakini (Chalkidiki, N. Greece)—were collected, and their chemical and mineralogical characterization analyzed with Energy-Dispersive X-ray Fluorescence (ED-XRF) and X-ray Diffractometry (XRD). Dry magnetic separation was used as a convenient enrichment method; however, no significant effect was shown in the chemical composition of separated (magnetic and non-magnetic) fractions, except for small increases in the olivine, antigorite and enstatite contents, which were observed in the non-magnetic fraction. Finally, the calcination of ground peridotites at 1520 °C, with the addition of CaO, Al2O3 and SiO2, presented a negative effect on the structure of the products with regard to their main refractory properties. In contrast, the addition of Cr2O3 and ΜgO mineral oxides showed improved refractory properties when compared with the initial material.