Arzenic-rich mineral assemblage in granite from Hora Svaté Kateřiny Škoda

 

Karel Breiter, Renata Čopjaková, Bedřich Mlčoch, Radek Škoda

Geoscience Research Reports 40, 2007 (GRR for 2006), pages 116–120
Map sheets: Litvínov (02-31)

Full text (PDF, 0.36 MB)

 

Abstract

Small stock of late-Variscan tin-specialised granite intruded lower Palaeozoic crystalline basement at Hora Svaté Kateřiny, Krušné Hory/Erzgebirge, NW Bohemia. The granite is geochemically specialised: enriched in F, Rb, Li, Sn, Nb, Ta, Th, Y, HREE, Be, As, and poor in P. Some textural features (magmatic brecciation and layering) reveal its subvolcanic character. Low content of phosphorus (<0.1 % P2O5 WR) in intruded silicic melt suppressed crystallisation of common accessory phosphates: monazite and xenotime are rare, apatite is completely absent. Major primary host of Y, HREE and Th are As-enriched zircon and zircon-thorite transitional phases containing 5-12 wt. % Y2O3, up to 32 wt. % of ThO2 and 1-2 wt. % As2O5. As-dominant minerals černovite and zircon-černovite transitional phases crystallized later during the hydrothermal stage.