RocksdayIron Meteorite vs Magnetite
The quickest way to tell Iron Meteorite from Magnetite: Magnetite is clearly harder: Mohs 5.5–6.5 versus 4–5.
Nickel-iron from the core of a melted asteroid. It is heavy, strongly magnetic, and shows a crisscross pattern on an etched slice.
Photo: Ji-Elle, Public domain
The most magnetic naturally occurring mineral. Black, heavy and often found as eight-sided crystals or as black sand on beaches.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Quick tests
- Hardness: Magnetite is clearly harder: Mohs 5.5–6.5 versus 4–5.
- Streak (rub on unglazed porcelain): Iron Meteorite leaves a gray streak; Magnetite leaves black.
- Heft: Iron Meteorite feels noticeably heavier for its size (specific gravity 7.3–8 vs 5.1–5.2).
- Texture: Iron Meteorite is a rock — a mix of grains or minerals; Magnetite is a single mineral.
Key differences
- Magnetite is also magnetic but lighter, and its streak is black.
Side by side
| Property | Iron Meteorite | Magnetite |
|---|---|---|
| Type | Igneous rock | Mineral |
| Mohs hardness | 4–5 | 5.5–6.5 |
| Luster | Metallic | Metallic |
| Streak | Gray | Black |
| Colors | Gray, Silver, Brown | Black |
| Crystal system / structure | Nickel-iron crystals (Widmanstätten pattern) | Cubic |
| Specific gravity | 7.3–8 | 5.1–5.2 |
| Formula | — | Fe₃O₄ |
| Found in | Canyon Diablo, Arizona; Gibeon, Namibia | Kiruna, Sweden; Adirondack Mountains, New York |
Properties that are the same for both are grayed out.
How to identify iron meteorite
- Very heavy for its size, and a magnet sticks hard.
- Thumbprint dimples (regmaglypts) or a rusty brown crust.
- No cubes. A gray streak, not the black streak of magnetite.
- A polished and etched slice shows interlocking bands.
Structure: Nickel-iron crystals (Widmanstätten pattern)
Full Iron Meteorite guide →How to identify magnetite
- Strongly attracts a magnet (some pieces are magnets themselves).
- Black streak.
- Heavy, black, metallic.
- Octahedral crystals when well-formed.
Crystal system: Cubic
Full Magnetite guide →More comparisons
Frequently asked questions
What is the difference between iron meteorite and magnetite?
Iron Meteorite is an igneous rock with a Mohs hardness of about 4–5 and a metallic luster, usually gray, silvery or brown. Magnetite is a mineral (Fe₃O₄) with a Mohs hardness of 5.5–6.5 and a metallic luster, usually black.
How can you tell iron meteorite from magnetite?
Magnetite is clearly harder: Mohs 5.5–6.5 versus 4–5. Iron Meteorite leaves a gray streak; Magnetite leaves black. Iron Meteorite feels noticeably heavier for its size (specific gravity 7.3–8 vs 5.1–5.2). Iron Meteorite is a rock — a mix of grains or minerals; Magnetite is a single mineral. Magnetite is also magnetic but lighter, and its streak is black.
Could you tell them apart from a blurry close-up?
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