Götzenite , Fluorite , Calcite Locality: Poudrette quarry (Demix quarry; Uni-Mix quarry; Desourdy quarry; Carrière Mont Saint-Hilaire), Mont Saint-Hilaire, Rouville RCM, Montérégie, Québec, Canada The götzenite blades (to ~ 12 mm) look like old ivory. Ex Ron Waddell. MOB coll. The label says "götzenite" and I thought this was my best. But I couldn't ID the orange micaceous looking flakes (top). So I tested for polylithionite with UV. No glow. But the götzenite (bottom) did glow. Strong lemony white (SW). Similar to elpidite from the Poudrette pegmatite. But it has now been verified (EDS) as götzenite by Tony S at ROM! Score one for Ron. The fluorescence is a mystery. Other götzenites from MSH do not fluoresce. Sept 2009: Updated using stacking and added stereo and "backside" views. As for the "micaceous" yellowish flakes, my old friend H. Cl tells me that they are calcite. So now it makes sense. This specimen is from marble xenolith - the usual hiding place for götzenite at MSH. — Photo: Modris Baum · Public domain
Götzenite
Götzenite is an IMA-recognized mineral species in the silicate class, with the chemical formula Ca₄NaCa₂Ti(Si₂O₇)₂(OF)F₂.
It crystallizes in the triclinic crystal system (space group P-1). It is a member of the Seidozerite-Rinkite structural group.
Key properties: specific gravity 3.03–3.14; Greasy luster; optically biaxial.
IMA symbol Göz, IMA status: approved, named in 1957.
Found in a nephelinite from the wall of the crater of an extinct volcano (Mt. Shaheru, Congo); in hornfels and marble xenoliths in an intrusive alkalic gabbro-syenite complex (Mont Saint-Hilaire, Canada).
It is found associated with Combeite (Mt. Shaheru, Congo); aegirine, apatite, fersmanite, pectolite (Kola Peninsula, Russia); cancrinite, fluorite, titanite (Azov region, Ukraine).
The name refers to Count Gustav Adolph von GÄotzen (1886{?), noted German traveller who climbed Mt. Shaheru, Congo (Zaire), in 1894.