SUMMARY
Preliminary study on tourmaline in
beryl-bearing pegmatite bodies
in the Sông Chảy Massif (Hà Giang Province)
Nguyễn
Văn B́nh, Phan Tiến Dũng, Trần Văn Soát
Tourmaline
is rather widespread in the Sông Chảy granitogneiss massif. The Sông Chảy
tourmaline occurs in the following formations: beryl- and tourmaline-bearing
mica pegmatite, tourmaline-bearing mica pegmatite, feldspar pegmatite,
tourmaline-bearing mica rocks, quartz-tourmaline
veins. Main mineral association: tourmaline, quartz, feldspar, muscovite,
biotite, phlogopite. The results of roentgen diffraction analysis show that the
Sông Chảy tourmaline is mainly dravite (belonging to the dravite-schorl
isomorphic series).
Ngày
nhận bài: 23/5/2007
Người biên tập:
Nguỵ Tuyết Nhung