Publikationsdatum:
2011-04-11
Beschreibung:
Tourmalines of unusual (mushroom) habit are common in granitic pegmatites of Momeik, northeast of Mogok, Myanmar. Here, we examine a sample of elbaite of significantly different habit, consisting of a series of diverging crystals, resembling a sheaf of wheat and ranging in colour from light purplish-red at the base to dark purplish-red at the tip with a thin green cap at the termination. The crystal structures of eight crystals are refined to R1-indices of [~]2.5% using graphite-monochromated Mo-K X-radiation; the same crystals were analysed by electron microprobe. 11B and 27Al magic angle spinning nuclear magnetic resonance (MAS NMR) spectra were collected on four regions of the wheatsheaf crystal, and show [~]0.3 a.p.f.u. [4]B and
Print ISSN:
0026-461X
Digitale ISSN:
1471-8022
Thema:
Geologie und Paläontologie
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