Mineral substance of the meteorite Chelyabinsk: infrared absorption, Raman and 57Fe Mossbauer spectroscopy

The brief review of researches of the meteorite Chelyabinsk is made, and our original results based on application of X-ray fluorescence analysis, X-ray diffraction, infrared, Raman and M ssbauer spectroscopy are presented. Spectroscopic characteristics of the meteoritic substance reflect specificity of its main mineral components. Olivine of the meteorite is quite homogeneous and significantly forsteritic, Fo70Fa30 in average composition. The secondary mineral phase is represented by orthopyroxene En 70-80Fs 30-20 and by a small amount of clinopyroxene En 46Fs 34Wo 20, which forms a binding intergrain component together with feldspar. In melting zones, the relative content of silicate forms of iron decreases as a result of the appearance of newly formed magnetite. According to M ssbauer spectroscopy, 70 to 90 % of iron locates in the structure of silicate substance - olivine and pyroxene - in the ratio 2.5:1. The other part of iron is mainly sulphidic and belongs to the troilite phase. In the meteorite, metal iron forms constitute its small part and can not be detected by M ssbauer spectroscopy in the bulk sample.