Abstract
Abstract. The textural appearance of Co-bearing pyrite was visualized
by a mapping method using a Raman microprobe. Two out of five Raman active
modes (Eg and Ag) of pyrite were evaluated here. The obtained
Raman map tightly correlates with a Co distribution map revealed by electron
microprobe. Both Eg and Ag modes gradually downshift and broaden
with increasing Co concentration. The broadening and shifting of the Ag
mode is stronger compared to the Eg mode. Especially the intensity of the
Ag mode drastically drops and diminishes in comparison to the Eg
mode. Both 532 and 633 nm lasers revealed the same variation in position and
width of the Eg and Ag modes. Only the intensity ratio of the modes
differed because of an energy-dependent resonance scattering from the Ag
mode. The 1064 nm laser was unsuitable since the Raman scattering intensity
is inversely proportional to wavelength. Furthermore, highly broadened Raman
modes at upshifted frequencies caused by the standard mechanical polishing
could be avoided by analyzing cut or polished samples with a broad ion
beam.
Subject
Pulmonary and Respiratory Medicine,Pediatrics, Perinatology and Child Health