Dr. Liu and others:
Although the chemistry appears to match for lithosite, other
properties do not. Lithosite is not reported to be "mica-like", but as
forming irregular grains with H = 5.5 (Mohs) and biaxial positive
optics, according to abstract in Am Min 69:210 (1984). Lithosite is
from Khibiny and is associated with orthoclase, sodalite, aegirine,
etc. Back to the drawing board?
>Dear sirs,
>A mineral which is extremely rich in potassium is found in two
rocks from
>greenschist belt.It looks like mica under thin section. The
coexisting
>minerals are actinolite, epidote, muscovite, albite and qtz. Some
EPMA
>analysis results are shown as following:
>
> No. SiO2 TiO2 Al2O3 FeO MnO MgO CaO
Na2O
>K2O Cr2O3 Total
>
> 1 45.401 0.232 20.169 0.000 0.000 2.525 0.166
0.129
>24.796 0.049 93.467
> 2 47.237 0.135 20.387 0.000 0.000 2.650 0.067
0.122
>24.809 0.059 95.466
> 3 46.899 0.217 21.157 0.000 0.000 2.541 0.071
0.115
>24.579 0.049 95.628
>I have checked for several possibilities but failed. Could anybody
tell me
>what is could be ?
>
>Thanks.
>
>R. Liu
++++++++++++++++++++++++++++++++++++
Edward S. Grew
Department of Geological Sciences
University of Maine
5790 Bryand Research Center
Orono, Maine 04469-5790 USA
Tel: 207-581-2169
Fax: 207-581-2202
E-mail: [log in to unmask]
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