Andreas Ertl1, John Rakovan2,
John
M. Hughes2, Heinz-Jürgen
Bernhardt3, and George
R. Rossman4
1Institut für Mineralogie und Kristallographie,
Geozentrum, Universität
Wien, Althanstraße 14, A-1090 Vienna, Austria
2Department
of Geology and Environmental Earth Science,
3Institut
für Geologie, Mineralogie und Geophysik, Ruhr-Universität Bochum,
D-44801
Bochum, Germany
4Division
of Geological and Planetary Sciences, California Institute of
Technology,
The
crystal structure of a green,
transparent, vanadium-rich 2M1
muscovite-2M1 (V2O3
= 11.35 wt%, one of the
highest amounts reported to date in muscovite) with the optimized formula (K0.94Na0.06)
(Al1.20V3+0.61Mg0.12Cr3+0.07)
(Si1.54Al0.46)T
1
(Si1.54Al0.46)T
2 O10 (OH)2 and space group
C2/c, a =
5.2255(6), b =
9.0704(10), c =
20.0321(21) Å, b = 95.773(2)º, Z = 4 has
been refined to R = 7.2% for 1,070 unique reflections (Mo Ka). This muscovite, which occurs in small
quartz veins in graphite schist from
Weinberg Mountain, near the village of Amstall,
In hand specimen, the mica appears as a thin green veins of mica flakes.
The optical spectrum arises from V3+.