The first occurrence of centimeter-thick PS-15 polygonal serpentine veins from ultramafics of Monte Avic, Val d'Aosta, is here reported. The combined mineralogical study led by three techniques with different resolutions has provided new analytical tools capable of recognizing the PS-15 polygonal serpentine. In particular, X-ray powder diffraction data (XRPD) and micro-Raman recognize polygonal serpentine more quickly and easily than transmission electron microscopy (TEM) but equally rigorously.

We report a comprehensive data set characterizing and quantifying two types of mineral defects in the most abundant mineral of Earth's upper mantle: olivine. Namely, we investigate translation defects of dislocation and rotation defects, called disclinations, in polycrystalline olivine deformed in uniaxial compression or torsion, at high temperature and pressure. The defects are identified via mapping of the crystallographic disorientation detected using electron backscatter diffraction.

When detecting the light element boron in solid materials with, in part, considerably lower concentrations of boron than present in natural tourmalines by using the electron microprobe, irregularities become visible in the analyses. This was for the first time experienced in synthetic diamond that was contaminated with boron to achieve a blue color. With this work, one can check if boron analyses are reasonable, and if not, one can correct them.

Stannite decomposition leads to the precipitation of an amorphous and metastable Sn–Fe–As-rich phase. With ageing, goethite and cassiterite crystallize from the precursor and mark the end of the weathering cycle. Other elements are lost in the initial stage of weathering (e.g. Zn, S) or after full oxidation of the sulfidic material (e.g. Cu, Ag). Electron microprobe (EMP) and transmission electron microscopy (TEM) analyses were performed to witness the mobility of the released elements.

Labradorite displays various structural features which have received attention in science for a long time. In this paper an electron microscopy study was performed investigating the hierarchical structure and connecting its features over several orders of magnitude. In addition, the atomic structure was solved with three-dimensional electron diffraction, showing results comparable to X-ray diffraction data and demonstrating the potential of the method to solve complicated crystal structures.