Two diamond-bearing meteorites (ALH-77257 and ALH-78113) were investigated by petrographic microscope and micro-Raman spectroscopy. The meteoritic diamonds can be found in fractures or veins cross-cutting the original minerals (olivine, pyroxene, feldspar) and inside the host minerals. The micro-Raman spectral features of microdiamonds in two studied meteorites are very similar to each other. The diamond peak was found at 1329 in ALH-77257 and 1332cm 1 in ALH-78113. Hexagonal diamond was not present. However, we observed the D and G bands of graphite or amorphous carbon at 1322 and 1582cm 1 wavenumbers, indicating an origin of the meteoritic microdiamonds by magmatic processes.
- melt pockets
- micro-Raman spectroscopy
ASJC Scopus subject areas
- Analytical Chemistry
- Atomic and Molecular Physics, and Optics