Abstract
NWA1950 is a typical lherzolitic shergottite similar to other samples of this Martian meteorite group. However olivine in NWA1950 shows strong dark color in thin sections and dark parts consist of crystallographically-controlled dark stripes present in colorless olivine crystal. Parallel stripes of 200-500 nm width were observed under TEM that are corresponding to dark stripes under optical microscope. Stripes are consist of tens-nanometer-sized minute crystals although they are inside of a single crystal. Dislocations are present in the surrounding host crystal, but not in stripes. Fe-rich nano-particles are concentrated in stripes. Nano-particles are usually 10-20 nm in diameter and do not contain Ni. The FFT patterns of these nano-particles are consistent with hematite.
