Tantalum-free niobium analogue of ixiolite from the Eifel paleovolcanic region, Germany, and its crystal structure

database, nuove specie, discrediti,
ridefinizioni, classificazioni, ecc.
Rispondi
Avatar utente
Marco E. Ciriotti
Messaggi: 27901
Iscritto il: ven 25 giu, 2004 11:31
Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
Contatta:

Tantalum-free niobium analogue of ixiolite from the Eifel paleovolcanic region, Germany, and its crystal structure

Messaggio da Marco E. Ciriotti » sab 10 apr, 2021 15:23

Referenza:
▪ Zubkova, N.V., Chukanov, N.V., Pekov, I.V., Ternes, B., Schuller, W., Pushcharovsky, D.Yu. (2020): Tantalum-free niobium analogue of ixiolite from the Eifel paleovolcanic region, Germany, and its crystal structure. On the problem of “ashanite”. Zapiski RMO (Proceedings of the Russian Mineralogical Society), 149(4), 125-134.

Abstract:
The crystal structure of a Ta-free Nb-dominant analogue of ixiolite with the empirical formula (Nb1.55Ti1.11Fe3+1.01Mn2+0.19Cr3+0.04Mg0.04Al0.03Zr0.02Mn3+0.01)S4O8 (Z = 1) from the Laach Lake area (Eifel, Germany) was solved based on single-crystal X-ray diffraction data and refined in the space group Pbcn to R = 4.47%. The unit-cell parameters are: a = 4.6578(6), b = 5.6230(7), с = 5.0182(5) Å, V = 131.43(3) Å3. The mineral belongs to the α-PbO2 structure type. It was found in volcanic nosean sanidinite, in a late (presumably, pneumatolytic) mineral association including sanidine, nosean, magnetite, ilmenite, biotite, corundum, and columbite-(Fe). The crystal chemistry of the ixiolite-like niobate is discussed, including the aspect related to the definition of the discredited mineral species “ashanite”.
Marco E. Ciriotti

«Things are interesting only in so far as they relate themselves to other things»

Rispondi

Chi c’è in linea

Visitano il forum: Bing [Bot] e 7 ospiti