Section of a transparent
Olivine crystal giving the Raman spectrum above.
Pyroxenes
The Diopside crystal on the left exhibits a weak Raman spectrum above a
huge fluorescence signal. After baseline correction, the spectrum can be
compared with the reference.
Thick section of a Pyroxenite with the
laser spot for Raman measurement indicated by the arrow. The spectrum
has similarities with the reference Enstatite data although some changes
in some peak positions can be noticed. This could be interpreted by a
different iron composition in both samples.
This pyroxenite sample has
also been studied previously by the
absorption spectroscopy.
This absorption spectrum is also characteristic of Otho Pyroxene.
Feldspars
Raman spectrum of the Labradorite sample on the left. The fluorescence
background is high compared to the Raman signal. This seemed to be
common in Feldspars: some other very clear samples gave nothing but
fluorescence. Comparison with 2 reference spectra of Feldspars can be
seen.
Sun Stone
Sun stone feldspar measured without any
sample preparation gives the spectrum above. This spectrum has strong
similarities with the Labradorite sample described above.
The nice red
inclusions have not yet been identified.
Microcline
Spectra of microcline from Italy recorded
with the new spectrograph. For one spectrum, colloidal silver particles
have been sprayed on the sample. No enhancement of the signal has been
noticed.