NEW OBSERVATIONS ON NATURAL PYRRIIOTITES Part IL Lamellar Magnetite in Monoclinic Pyrrhotite
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چکیده
Monoclinic pyrrhotite from Norseman, Western Austra"lia, has lamellae of submicrometer thickness, identified by microprobe and electron diffraction as magnetite. The lamella zurface is (111) of magnetite parallel to (001) of pyrrhotite, corresponding to a close fit of close-packed planes of the two structures' The perfect lamellar nature of the magnetite in unaltered pyrrhotite indicates origin by exsolution, requiring solid solution of oxygen in earlier pyrrhotite.
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