Abstract:
Small bluish-grey spots are observed very often in polished sections of ordinary brownish-grey magnetite. Study realized on hundreds of samples from the Kola banded iron ore formation (BIF) has shown the presence of both «bluish» and «brownish» magnetites in 30 % of the BIF ores. The «bluish» magnetite has the higher iron grade, comparatively to the brownish phase, and physical properties of magnetites containing one (brownish) or both phases are more diverse than those of magnetites differing by the trace elements content only.
