Journal of

GEOsciences

  (Formerly Journal of the Czech Geological Society)

Original Paper

Pavel Povondra, Stanislav Vrána

Crystal chemistry of apatite in tourmaline-bearing alkali-feldspar orthogneiss near Hluboka nad Vltavou, southern Bohemia

Journal of the Czech Geological Society, volume 38 (1993), issue 3-4, 165 - 170

Accessory fluorapatite from three samples of tourmaline-bearing alkali-feldspar orthogneiss was analyzed by methods of wet analysis; rare earth elements were also determined. MnO contents range from 2.11 to 2.84 wt.%, FeO from 0.86 to 2.38 wt.%, REE oxides from 0.36 to 1.02 wt.%, and Na₂O from 0.54 to 1.20. The chemical composition of apatite including its fluorine content indicates primary magmatic crystallization. The increased contents of Fe, Mn, and REE, and the relative concentrations of Mn - Mg - Fe and La - Ce - Y in these fluorapatites correspond to those of apatites from pegmatites. Apatite is deformed and no post-deformation growth was observed.