Phonolite from
Germany | |
| A former H. Westenberger, Kelkheim, Germany, specimen (label), from the Stefan Stolte collection, Frankfurt (#854). |
| Spürgin, Simon & Weisenberger, Tobias & Marković, Marija. (2019) Zeolite-group minerals in phonolite-hosted deposits of the Kaiserstuhl Volcanic Complex, Germany. American Mineralogist. 104:659-670. 10.2138/am-2019-6831. |
| media.lgrb-bw.de (n.d.) https://media.lgrb-bw.de/link/gto/gto_6457.pdf |