Rock magnetism is useful in
various applications. Hematite is one of the two most important carriers of
magnetism in the natural world and its magnetic features were mostly studied
through laboratory experiments using synthetic hematite samples. A gap exists
between the magnetic behaviors of hematite contained in the natural rocks and
ores and those of synthetic hematite samples. This paper presents the results
of a rock magnetism study on the natural hematite ores from the Whaleback mine
in the Hamersley Province in the northwest of Western Australia. It was found
that high-grade hematite ores carry a much higher remanent magnetization than
induced magnetization. Hematite ores with less than 0.1% magnetite appear to
have an exponential correlation between the bulk susceptibility and hematite
content in weight percentage, different from the commonly accepted linear
relationship between the bulk susceptibility and hematite content obtained from
synthetic hematite samples. The new knowledge gained from this study
contributes to a better understanding of magnetic behaviors of hematite,
particularly natural hematite, and hence applications to other relevant disciplines.
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