Journal of

GEOsciences

  (Formerly Journal of the Czech Geological Society)

Original Paper

Pavel Povondra, Miloš Lang, Edvín Pivec, Jaromír Ulrych

Tourmaline from the Přibyslavice peraluminous alkali-feldspar granite, Czech Republic

Journal of the Czech Geological Society, volume 43 (1998), issue 1-2, 3 - 8

Chemical composition of tourmaline from the Přibyslavice alkali-feldspar granite (3 km²) in Moldanubian metamorphosed series in eastern Bohemia, is characterized by five wet and 43 microprobe analyses. The composition of the touramaline varies considerably from magnesium-rich FE₆₁Mg₃₆Al₃ to magnesium-poor Fe₈₄Mg₉Al₇ proton- and alkali-deficient schorl. Zoning of tourmaline is weak, however, the chemical differences between cores and rims are systematic: the ion content lowers from core to rim. A small deficiency of Si in the tourmalines is characteristic. In terms of the genetic classification, based on the proportion Al-Fe-Mg, the studied tourmalines belong to association of Li-poor granitoids, their pegmatites and aplites.