The muscovite, transparent on a transmission image is
a major mineral in this rock sample. It appears with brilliant
interference colors throughout the
On the reflection image (left below), the muscovite appears dark due to
the light absorption of the minerals deeper in the section (glaucophane)
Muscovite Raman spectra at 532 nm.
With the red laser, spurious lines appear in the Raman spectrum. Those
lines are absent in spectra got with green laser. Fluorescence? To be
Picture of the opaque minerals. Magnetite and
hematite have been identified in this section. Hematite has a higher
Hematite Raman spectrum compared with a pure hematite sample.
Magnetite is also identified by Raman. The intensity of the laser should
be decreased to see the magnetite spectrum. If light intensity is too
high, the magnetite is oxidized and an hematite spectrum is obtained.