Definition of magnetite in English:



  • A gray-black magnetic mineral that consists of an oxide of iron and is an important form of iron ore.

    • ‘In part, the hypothesis involved tiny grains of the naturally magnetic mineral magnetite, which is commonly found in basalt (a high-temperature volcanic rock that makes up oceanic crust).’
    • ‘Nearby is a magnet, composed of natural magnetite, that once belonged to Lomonosov.’
    • ‘The majority of the rhyolites are porphyritic and contain phenocrysts of one or more of the following: plagioclase, clinopyroxene, magnetite, quartz and sanidine, plus accessory apatite and zircon.’
    • ‘Spinels in the country rock are essentially pure magnetite.’
    • ‘Along the contact zone the limestones were recrystallized into a cloudy white, massive calcite containing grossular, epidote, magnetite, quartz, and tremolite.’
    • ‘The dominant carrier of remanent magnetization of the doleritic rocks is relatively pure magnetite of pseudo-single domain size, and the characteristic remanent magnetizations are typically well defined and unidirectional.’
    • ‘The third potential way the hematite could have formed is by oxidation of a mineral called magnetite in basalt and lavas.’
    • ‘The new ‘evidence’ is tiny (one-millionth of an inch in diameter) crystals of magnetite, a magnetic oxide of iron.’
    • ‘Chemically, Strain 121's respiration process reduces ferric iron to ferrous iron and forms the mineral magnetite, the source of most of the magnetic material deposited on Earth some two billion years ago.’
    • ‘The replacement of the authigenic magnetite by hematite probably occurred at the same time as the specular hematite that surrounds the dolomite grains.’
    • ‘The palaeomagnetic analyses of this study have revealed that the dominant carrier of remanent magnetization of the Whin Sill dolerite is relatively pure magnetite in the pseudo-single domain size range.’
    • ‘In the left test tube, a magnet attracts magnetite, the byproduct of Strain 121's respiration of iron oxide and offers a tell-tale sign of life in the tube.’
    • ‘More important, because the presence of magnetite gives the basalt measurable magnetic properties, these newly discovered magnetic variations provided another means to study the deep ocean floor.’
    • ‘The magnetite, uralite, and other minerals can be exposed by etching away the enclosing calcite with hydrochloric acid.’
    • ‘Microscopic analyses reveal that the oxide mineralogy of the dolerites is dominated by magnetite and ilmenite.’
    • ‘The sedimentary clasts also contain abundant opaque minerals, chiefly magnetite.’
    • ‘This colour change occurs over only a few metres on the ground and is probably related to the reduction of hematite to magnetite.’
    • ‘The sample is composed of K-feldspar, plagioclase and quartz with accessory apatite, magnetite, titanite, zircon and secondary epidote.’
    • ‘The claims centre on a mineral with a high iron content called magnetite, which is found embedded in the Martian rock in an unusual form.’
    • ‘Lodestones are simply naturally occurring magnets composed of the magnetic mineral magnetite.’
    lodestone, magnetite
    View synonyms


Mid 19th century: from magnet + -ite.