Record details

Title
    Ferrotapiolite as a pseudomorph of stibiotantalite from the Laštovičky lepidolite pegmatite, Czech Republic; an example of hydrothermal alteration at constant Ta/(Ta+Nb)
Author
    Cempírek, Jan
    Černý, Petr
    Filip, Jan
    Novák, Milan
    Šrein, Vladimír
Language
    anglicky
Publication type
    článek v periodiku
Source title - serial
    Canadian Mineralogist
Vol./nr.
    Roč. 42, č. 4
Pages
    12
Year
    2004
Thesaurus term
    an example of hydrothermal alteration at constant Ta/(Ta+Nb)
    Czech Republic
    Ferrotapiolite as a pseudomorph of stibiotantalite from the Laštovičky lepidolite pegmatite
Keyword
    Alteration
    Constant
    Czech
    Example
    Ferrotapiolite
    Hydrothermal
    Laštovičky
    Lepidolite
    Pegmatite
    Pseudomorph
    Republic
    Stibiotantalite
    Ta/(Ta+Nb
Abstract (in english)
   Dark brown porous ferrotapiolite is a dominant alteration product in pseudomorphs after primary stibiotantalite from the lepidolite pegmatite at Laštovičky, western Moravia, Czech Republic. Two compositionally distinct varieties of ferrotapiolite were recognized a volumetrically dominant Fe3+-rich phase and a very rare Sb-rich phase. Niobium-rich ferrotapiolite, with up to 17.51 wt.% Nb2O5 (0.61 apfu), is highly heterogeneous with Ta/(Ta+Nb) of 0.69 to 0.84 and Mn/(Mn+Fe) of 0.01 to 0.05; Fe2O3calc. 3.09 wt.% (0.18 Fe3+ apfu; ~ 0.16 to 0.22 Fe3+ apfu from Mössbauer spectroscopy) in the ferrian, and Sb2O3 9.87 wt.% (0.34 Sb3+ apfu) in antimonoan variety. The unit-cell dimensions of ferrian ferrotapiolite a = 4.746-4.757 ? and c = 9.198-9.244 ? calculated from X-ray powder diffraction data indicate highly variable degrees of structural order.
Contributor
    MU Brno, Přírodovědecká fakulta
Contributor code
    MU, PřF
Source format
    R
Import date
    8. 8. 2012