A systematic study of a large set of moldavites and the application of cathodoluminescence (CL)‐spectroscopy with a detailed discussion of spectral features is presented. Optical CL microscopy and spectroscopy (OM‐CL) were performed on 57 moldavite samples from different substrewn‐fields in Germany and the Czech Republic. The extracted CL data were supported by SEM‐EDX analysis. In general, two different kinds of CL colors can be distinguished: different shades of green in the matrix of the tektite glasses and a variation of blue color for lechatelierite inclusions (a pure silica‐glass phase). Spectral analysis of these colors shows three CL emission bands for green and five bands for blue c. Most CL activators are structural defects of the local glass network, influenced by the crystal field. The visible green CL emission is caused by defects related to strong local disorder as well as Al‐O−‐Al defects. The blue CL emission is activated by different types of lattice defects such as nonbridging oxygen‐hole center (NBOHC), self‐trapped excitons (STE), and oxygen deficiency centers (ODC). Intensity variations of the CL emissions were observed for samples from the different localities, but there is no direct correlation between substrewn‐fields and CL characteristics. Nevertheless, CL microscopy is a powerful tool for the high‐contrast visualization of internal textures such as streaks and lechatelierite in the tektite matrix due to the luminescence properties of the defect structures in the glassy network.

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<p>The Brandholz/Goldkronach district is situated in the southeastern part of Germany in the Bavarian Fichtelgebirge. Previous literature of the mineralogy of the district is rather descriptive and modern geochemical analysis are entirely missing. In this contribution, we combine petrography, bulk rock-geochemical analysis, SEM-MLA as well as EPMA to infer on precipitation mechanism and ore-forming processes. The quartz-polymetallic-sulfide veins are hosted in Ordovician shists, called “Phycodenschiefer”, which were intruded by upper Devonian meta-basalts. Antimony-sulfides are the main ore mineralization inside of the quartz-veins, accompanied by minor auriferous arsenopyrite and pyrite. Petrographic observations suggest a precipitation of an early stibnite phase (stage I). Sb-Pb-sulfides/sulfosalts (stage II) precipitated in fractures and fissures of stage I stibnite with a slightly change to Pb-rich Sb-phases. The antimony-mineralization event evolved from stibnite (Sb<sub>2</sub>S<sub>3</sub>), over fülöppite (Pb<sub>3</sub>Sb<sub>8</sub>S<sub>15</sub>), zinkenite (Pb<sub>9</sub>Sb<sub>22</sub>S<sub>42</sub>), plagionite (Pb<sub>5</sub>Sb<sub>8</sub>S<sub>17</sub>) to boulangerite (Pb<sub>5</sub>Sb<sub>4</sub>S<sub>11</sub>). Chemical analyses corroborate the petrographic observations and indicate a change in the hydrothermal environment from a Sb- to Sb-Pb dominated system with a distinct geochemical change from Pb-free to Pb-containing Sb-phases. A characterization of the precipitation sequence can be used to improve the understanding of the hydrothermal evolution of the whole Sb-Au-ore system in Goldkronach.</p>