Raman Gabbro from Scotland.

                     Wide field thin section of this rock.             Raman spectra of the opaque minerals.

    

 

           Six areas in a Gabbro thin section from Scotland analyzed with Raman microscopy.

   Hastingsite, Pargasite, Forsterite, Diopside, Labradorite...

 

         The spectrum of the green area 1, slightly pleochroic green to yellow, could be interpreted as hastingsite, a member of the hornblende family although the spectrum of the thin section is not perfect in this area.

         The small brown green area 6 has a Raman spectrum similar to pargasite, another member of the hornblende family.

     The black area 2 gives surprisingly a spectrum of forsterite plus additional peaks. The clear crystal in area 3 surrounded by the black material is forsterite. The subtraction of both spectra should give the spectrum of the black material (green curve on the left). Up to now, this spectrum has not been identified, it is probably oxidation of the opaque original material by the laser.

  The feldspar in area 4 is labradorite very common in this rock section.

      Most of the high color interference minerals of this section are diopside as shown on the two spectra on the left. Diopside has a high relief and a brownish color in LPNA view.
 

                             Raman analysis of Gabbro areas 8, 9 and 10

The black region 8 gives the spectrum on the left. This black mineral is not yet identified.

The area 9 surrounded by the black minerals is again forsterite.

 

                                           Raman spectra of Gabbro areas 11 and 12.

The green brown areas 11 and 12 have spectra similar to region 1 above, they could be amphibole of the hornblende family. They are slightly pleochroic green-yellow and yellow green to brown. Signal to background ratio of those spectra are rather poor.