Articles | Volume 38, issue 1
https://doi.org/10.5194/ejm-38-75-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/ejm-38-75-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Feb 2026
Research article |
| 24 Feb 2026
| 24 Feb 2026
Crystal structure, chemical composition, and twinning of götzenite and wöhlerite from the Fohberg phonolite, Kaiserstuhl
Reinhard X. Fischer
CORRESPONDING AUTHOR
Fachbereich Geowissenschaften, Universität Bremen, 28359 Bremen, Germany
Johannes Birkenstock
Fachbereich Geowissenschaften, Universität Bremen, 28359 Bremen, Germany
Georg Biskup
independent researcher: Pforzheim, Germany
Lennart A. Fischer
Institut für Geo- und Umweltwissenschaften, Geochemie, Albert-Ludwigs-Universität, Freiburg, Germany
Andreas Klügel
Fachbereich Geowissenschaften, Universität Bremen, 28359 Bremen, Germany
Shaghayegh Nezamabadi
Fachbereich Geowissenschaften, Universität Bremen, 28359 Bremen, Germany
Simon Spürgin
Hans G. Hauri KG, Bötzingen, Germany
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Short summary
Götzenite and wöhlerite were found as part of a fissure assemblage in the Fohberg phonolite (Kaiserstuhl, SW Germany) in close contact to each other. Götzenite shows rotation twinning on [001], and wöhlerite shows reflection twinning on (100). Götzenite represents a special case, where the twin domains are arranged in a certain way with the main axis nx of the optical indicatrix being parallel to the twin axis c in both domains.
Götzenite and wöhlerite were found as part of a fissure assemblage in the Fohberg phonolite...
