Record details

Title
    Schorl-oxy-schorl to dravite-oxy-dravite tourmaline from granitic pegmatites; examples from the Moldanubicum, Czech Republic
Author
    Novák, Milan
    Povondra, Pavel
    Selway, Julie Beryl
Language
    anglicky
Publication type
    článek v periodiku
Source title - serial
    European Journal of Mineralogy
Vol./nr.
    Roč. 16, č. 2
Pages
    11
Year
    2004
Thesaurus term
    Czech Republic
    examples from the Moldanubicum
    Schorl-oxy-schorl to dravite-oxy-dravite tourmaline from granitic pegmatites
Keyword
    Czech
    Dravite-oxy-dravite
    Examples
    Granitic
    Moldanubicum
    Pegmatites
    Republic
    Schorl-oxy-schorl
    Tourmaline
Abstract (in english)
   Wet-chemical analyses (41) of tourmaline from granitic pegmatites (barren, barren-pocket, beryl, lepidolite types) in the Moldanubicum, Czech Republic revealed that members of the oxy-subgroup ĄV common oxy-schorl, minor oxy-dravite and rare oxy-foitite are more abundant relative to the relevant members of the hydroxy-subgroup. The primary substitution mechanisms in tourmaline show combination of heterovalent substitutions: YAlWO YR2+-1W(OH)-1, XďYAl2WO XNa-1YR2+-2W(OH)-1, XďYAl XNa-1YR2+-1 and Xď W(OH) XNa-1WO-1, and homovalent substitutions: Fe2+Mg-1 and (OH)F-1. Tourmalines with the chemistry expressed by the general formula X(Na0.5ď0.5)Y(R2+2Al)ZAl6(BO3)3Si6O18V(OH)3W(O0.5OH0.5) crystallized in very similar PT conditions in granitic systems saturated on Na, Al, Si and H2O, it indicates the importance of short-range order requirements on tourmaline chemical composition.
Contributor
    MU Brno, Přírodovědecká fakulta
Contributor code
    MU, PřF
Source format
    R
Import date
    8. 8. 2012