1. Mineralogy Department, Institute for Geosciences, Friedrich‐Schiller University Jena, Carl‐Zeiss‐Promenade 10, 07745 Jena, Germany, http://www.geo.uni‐jena.de
2. Department of Mineralogy and Petrography, Natural History Museum, Burgring 7, 1010 Vienna, Austria
3. Institute of Mineralogy and Crystallography, University of Vienna, Geocentre, Althanstr. 14, 1090 Vienna, Austria