LithoMap

Mineral identification comparison

Ilmenite vs. magnetite: how to tell them apart

Ilmenite and magnetite are dense black iron-bearing oxides that commonly occur together in igneous rocks and heavy-mineral sands. Magnetite is normally strongly magnetic; ilmenite is weakly magnetic or nonmagnetic unless altered or intergrown.

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Black submetallic massive ilmenite hand specimen with uneven weathered surfaces
IlmeniteIron titanium oxide · FeTiO₃Photo: Darla Sondrol · CC0 1.0
Black metallic magnetite crystal specimen
MagnetiteIron oxide mineral · Fe₃O₄Photo: Robert M. Lavinsky · CC BY-SA 3.0
Quick answer

The most useful distinction

Compare magnetic strength with a known magnet, then streak. Strong attraction and black powder favor magnetite; weak response with black to brownish-red powder may favor ilmenite.

Side-by-side evidence

Ilmenite and Magnetite comparison table

PropertyIlmeniteMagnetiteHow to use it
MagnetismUsually weak, absent, or variableUsually strongly attracted to a magnetThe fastest field distinction on clean grains.
StreakBlack to brownish redBlack to dark grayA brown-red cast can support ilmenite but is not universal.
Crystal habitThick tabular, granular, or massiveOctahedral, granular, or massiveComplete crystals may help; sand grains usually do not.
AlterationMay alter toward pale titanium-rich leucoxeneMay oxidize toward hematite or maghemiteWeathering can weaken or complicate magnetic and streak responses.
Field sequence

A practical identification sequence

  1. 1

    Separate a few clean grains from attached matrix without grinding.

  2. 2

    Compare their response to the same known magnet at the same distance.

  3. 3

    Make a small streak if grains are large enough and expendable.

  4. 4

    Use reflected-light microscopy or chemistry for mixed concentrates.

Limits and cautions

Where the distinction gets difficult

  • Magnetite-ilmenite intergrowths may respond strongly despite abundant ilmenite.
  • A magnet separates magnetic behavior, not mineral identity by itself.
  • Avoid inhaling fine black-sand or mine-concentrate dust.

Use several independent observations. This comparison supports preliminary field identification, not laboratory confirmation, appraisal, proof of origin, or collecting permission.

Common questions

Ilmenite vs. magnetite FAQ

Is ilmenite magnetic?

Pure ilmenite is generally weakly magnetic or nonmagnetic in a simple hand test, but intergrowths, exsolution, and alteration can increase its response.

Can ilmenite and magnetite occur in one grain?

Yes. Microscopic intergrowths and exsolution textures are common and can make field separation unreliable.

Is every strongly magnetic black sand magnetite?

No. A concentrate can include several minerals and industrial fragments, although strong attraction makes magnetite a leading possibility.

Source basis

Authoritative sources

LithoMap wrote this comparison in original language from the physical properties and geological concepts supported by these public scientific references.

Editorial review: September 17, 2026.

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