REE-OXYFLUORIDES FROM THE CINOVEC GRANITI C CUPOLA, CZECH-REPUBLIC

Authors
JOHAN Z JOHAN V
Citation
Z. Johan et V. Johan, REE-OXYFLUORIDES FROM THE CINOVEC GRANITI C CUPOLA, CZECH-REPUBLIC, Comptes rendus de l'Academie des sciences. Serie 2, Mecanique, physique, chimie, sciences de l'univers, sciences de la terre, 318(10), 1994, pp. 1333-1340
Citations number
24
Categorie Soggetti
Multidisciplinary Sciences
Journal title
Comptes rendus de l'Academie des sciences. Serie 2, Mecanique, physique, chimie, sciences de l'univers, sciences de la terre → ACNP
ISSN journal
07644450
Volume
318
Issue
10
Year of publication
1994
Part
2
Pages
1333 - 1340
Database
ISI
SICI code
0764-4450(1994)318:10<1333:RFTCGC>2.0.ZU;2-9
Abstract
Subhedral opaque crystals consisting of submicroscopic intergrowths of REE-oxyfluorides occur in the zinnwaldite granite of the Cinovec (Zin nwald) granite cupola, Czech Republic. The following mineral phases we re observed: 1. Ce4O5F2 with fluorite-type structure, a=5.470(8) angst rom and a possible hexagonal or tetragonal superstructure; 2. (Ce,La,N d)OF, with a hexagonal, bastnaesite-type, unit-cell, a=7.007(10), c=9. 840(15) angstrom; 3. (La,Ce,Nd,Pr)F2.73O0.13 having LaF3-type structur e with a=7.153(10), c=7.365(10) angstrom. This intergrowth is probably due to the fluorination and hydrolysis of homogeneous (Ce,La,Nd,Pr)2O 3 crystals by interaction with a F- and H2O-rich fluid phase.