Mineral guide
How to Identify Magnetite
Fe₃O₄
Magnetite is a strongly magnetic iron oxide (major iron ore). Identify it by a magnet grab, black metallic color, and black streak — hematite streaks red-brown instead.
About Magnetite
Magnetite is a strongly magnetic iron oxide (major iron ore). Identify it by a magnet grab, black metallic color, and black streak — hematite streaks red-brown instead.
Magnetite is filed under minerals in the RockScan directory. Composition: Iron(II,III) oxide. It forms via magmatic, metamorphic, and sedimentary iron deposits. Typical occurrence: Sweden, USA, Russia, Australia, South Africa. For the broader method, see how to identify rock types.
Magnetite properties
| Mohs hardness | 5.5–6.5 |
|---|---|
| Class | mineral |
| Scientific name | Fe₃O₄ |
| Color | Black |
| Luster | Metallic |
| Crystal system / texture | Cubic |
| Composition | Iron(II,III) oxide |
| Formation | Magmatic, metamorphic, and sedimentary iron deposits |
| Occurrence | Sweden, USA, Russia, Australia, South Africa |
How to identify Magnetite
- Strongly magnetic.
- Black metallic; black streak.
- Hardness ~5.5–6.5; dense.
Lookalikes to rule out
- Hematite: Hematite streak red-brown; magnetite streak black and strongly magnetic.
- Ilmenite: Ilmenite is weakly magnetic at most; magnetite grabs a magnet strongly.
- Chromite: Chromite is less magnetic and often in ultramafic association; magnetite magnetism is decisive.
Photo tips for Magnetite ID
- Show a magnet attracting the specimen if safe.
- Octahedral crystals photograph well on contrasting matrix.
- Metallic black needs careful exposure.
Snap one specimen in natural light, then open the result in the online studio or the rock identifier app.
Magnetite FAQ
How do you identify magnetite?
A magnet sticks strongly. Black streak and metallic black color support the ID.
Is lodestone magnetite?
Lodestone is naturally magnetized magnetite.
Magnetite in beach sand?
Yes — black magnetic sand grains are often magnetite.
How to identify magnetite
Collectors search “how to identify magnetite” when a black metallic grain might be hematite or ilmenite. Use this field checklist:
- Magnetism: strongly attracts a magnet — the fastest field tell among common iron oxides.
- Streak: black streak on unglazed porcelain; hematite streaks red-brown.
- Color & luster: black metallic; dense; hardness ~5.5–6.5.
- Habit: octahedral crystals common; also massive grains in igneous/metamorphic hosts.
- Photo first: show magnet attraction safely, then confirm with RockScan against hematite.
Magnetite vs hematite vs ilmenite vs chromite
- Hematite: Red-brown streak and weaker/no strong grab; magnetite streaks black and grabs a magnet.
- Ilmenite: Weakly magnetic at most; magnetite pulls strongly.
- Chromite: Less magnetic, often ultramafic association; magnetite magnetism is decisive.
Photo tips for magnetite ID
Magnet attraction demo, octahedral faces on contrasting matrix, and careful metallic exposure. Compare hematite, pyrite, and gabbro hosts, then confirm in the online studio or rock identifier app.
Related minerals to compare
Browse all: rocks · minerals · crystals · directory · what rock is this · rock vs mineral vs crystal. Confirm with the online studio or rock identifier app.