Genthelvite and bertrandite from the Cairngorm Mountains, Scotland
- 14 March 1967
- journal article
- Published by Mineralogical Society in Mineralogical Magazine and Journal of the Mineralogical Society
- Vol. 36 (277) , 60-63
- https://doi.org/10.1180/minmag.1967.036.277.08
Abstract
Summary: A zinc-rich helvine (genthelvite) has been found with bertrandite in miarolitic cavities in adamellite at Coire an Lochain in the Cairngorm Mountains. The genthelvite occurs as green or brown tetrahedral crystals of sp. gr 3·58±0·01. It is isotropic, n 1·742±0·003, a 8·133±0·005 Å. Bertrandite crystals are pale brown with sp. gr. 2·60±0·01; biaxial negative with 2V 75°, and α 1·590, β 1·603, γ 1·613, all ±0·003.Keywords
This publication has 3 references indexed in Scilit:
- Beryllium minerals in Cornwall and Devon: helvine, genthelvite, and danaliteMineralogical Magazine and Journal of the Mineralogical Society, 1961
- Note on an occurrence of bertrandite and beryl at the South Crofty mine, Cornwall (With Plate XXV.)Mineralogical Magazine and Journal of the Mineralogical Society, 1940
- On the occurrence of Bertrandite at the Cheesewring Quarry, near Liskeard, CornwallMineralogical Magazine and Journal of the Mineralogical Society, 1911