LEIFITE, REVISED, AND KARPINSKYITE, DISCREDITED
to be a beryllium mineral and its composition has been redetermined by spectrographic analysis, thermogravimetric analysis, electron mi-croprobe measurements, and wet micro-chemical analysis. The for-mula can be written as: (Na, H30)2 [(Si, Al, Be, B)7 (O, F, OH)ML Z = 3 The mineral is trigonal, the...
| Main Authors: | , , , |
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| Format: | Text |
| Language: | English |
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| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.490.1366 http://2dgf.dk/xpdf/bull20-02-134-151.pdf |
| Summary: | to be a beryllium mineral and its composition has been redetermined by spectrographic analysis, thermogravimetric analysis, electron mi-croprobe measurements, and wet micro-chemical analysis. The for-mula can be written as: (Na, H30)2 [(Si, Al, Be, B)7 (O, F, OH)ML Z = 3 The mineral is trigonal, the probable space groups are P321 and P312, and the unit cell dimensions are: aQ = 14.351 Å and CQ = 4.854 A. The redefinition of Leifite has been approved by IMA. Karpinskyite from the type locality, Karnasurt pegmatites, Kola, has been investigated by scanning electron microscope, optical mi-croscope, X-ray diffraction and electron microprobe. The karpin-skyite is shown to be a mixture of leifite, montmorillonite and sau-conite. The name »karpinskyite « is discredited. The discrediting of karpinskyite has been approved by IMA. The leifite from Kola con-tains slightly less Si and slightly more Na and Al than the leifite from Greenland, and has the lattice constants a0 = 14.400 Å and c0 = 4.881 A. |
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