Native iron is a rare terrestrial mineral typically found in basaltic rocks or as a major component of metallic meteorites. It is strongly magnetic and prone to oxidation, requiring careful storage to prevent rust. Collectors prize samples for their significant weight and extraterrestrial or unique geological origins.
Is this iron?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch iron with a known reference. Iron sits at Mohs 4, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: gray.
- 3Read the lusterHold the specimen under a strong light. Luster: metallic.
- 4Match the color rangeCompare against the expected color range: steel gray, iron black, dark gray.
- 5Look at form & habitCrystal system: cubic. Typical habit: disseminated, granular, massive.
Often confused with
Iron vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Magnetite is the harder of the two (Mohs 5.5-6.5 vs. 4); streak differs, so Iron leaves gray, Magnetite leaves black.
How to tell apart: Hematite is the harder of the two (Mohs 5-6 vs. 4); streak differs, so Iron leaves gray, Hematite leaves cherry-red or reddish brown.
Often found alongside iron
Minerals reported to co-occur with iron. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Fe
- Mohs hardness
- 4
- Density
- 7.3-7.87 g/cm³
- Streak
- Gray
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Cubic
- Crystal habit
- Disseminated, granular, massive
- Cleavage
- {001}; parting on {112}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Rare in igneous rocks, especially basalts; in carbonaceous sediments; in volcanic fumaroles; and in petrified wood, mixed with “limonite” and organic matter
Where rockhounds find iron
18 mapped spotsClassic worldwide localities
- Cameron, Clinton Co., Missouri, USA
- New Brunswick, Somerset Co., New Jersey, USA
- Fortune Bay, Mellemfjord, Asuk, on the west coast, Greenland
- Disko Island, near Uivfaq and Kitdlı̂t, Greenland
- Ben Bhreck, Scotland
- Bühl, near Weimar, Hesse, Germany
U.S. states with iron
Each link opens a state-specific list of mapped rockhounding spots that produce iron.
Field-hunting tip
Where it forms: Rare in igneous rocks, especially basalts; in carbonaceous sediments; in volcanic fumaroles; and in petrified wood, mixed with “limonite” and organic matter. If you start seeing pyrite, magnetite, troilite in float, you are in the right ground. Typical habit: disseminated, granular, massive. Train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Minnesota, Nevada, Georgia. Start trip planning there.
Common questions
How do you identify iron?+
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What rocks look like iron?+
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Find iron on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
