Beryllium and other trace elements in paragneisses and anatectic veins of the ultrahigh-temperature Napier complex, Enderby land, East Antarctica: The role of sapphirine

Abstract

Anatectic veins containing the Be minerals khmaralite and beryllian sapphirine as primary phases (or surinamite derived therefrom) are associated with Mg-Al-rich paragneisses at three localities in the ultrahigh-temperature Napier complex, Antarctica, a unique Be mineralization in the granulite facies. Likely precursors of the paragneisses are volcaniclastic deposits that were hydrothermally altered by heated seawater prior to metamorphism. Regular distribution of Be among minerals in the paragneisses suggests an approach to equilibrium with Be greatly concentrated in sapphirine (25-3430 ppm Be) or cordierite (560-930 ppm Be) relative to plagioclase An53-66 (14-43 ppm Be) > cores of coarse-g..