Mössbauer spectroscopy, x-ray diffraction, and electron microprobe analysis of the New Haifa meteorite

Abstract

Mössbauer spectroscopy, x-ray diffraction (XRD) measurements, and electron microprobe analysis (EMPA) have been carried out for the investigation of a newly fallen Sudanese meteorite named New Haifa. The room temperature Mössbauer spectrum is fitted with three sextets and two doublets. The sextets are assigned to Fe in troilite, kamacite, and taenite, and the two doublets are assigned to Fe2+ in olivine and pyroxene (no Fe3+ was found). The microprobe trace of Ni concentration across a kamacite-taenite-kamacite area shows a high-Ni concentration at the interfaces between kamacite and taenite. From the microprobe analysis, olivine appears to have a constant composition, whereas pyroxene has a varying composition. The mole fractions of the Fe end members of olivine (fayalite) and pyroxene (ferrosilite) are found to be 23.5% and 23.2%, respectively. Accordingly, the New Haifa meteorite is classified as an ordinary L-type chondrite.