Investigation of structure and phase composition of the Chelyabinsk meteorite

Six principal phases are found in the meteorite: three Fe Ni solid solutions with different crystal lattices and nickel concentrations (α-kamacite with 3.5-5.5 at. % Ni, γ-taenite with 38-43 at. % Ni and ordered Fe Ni phase with the cubic lattice), iron sulphides Fe 1-xS x, olivine Mg 1,727Fe 0,273SiO 4 and aluminum silicates Al 2Si 24O 51. Metallic particles contain α and γ solid solutions separated by distinct interfaces. High-angle boundaries within both phases are not revealed. Unlike a and y phases harder sulphides are present as aggregates of grains with well-defined high-angle boundaries.