RocksdayCuprite vs Hematite
How to tell them apart
Copper oxide forming deep red cubes and octahedrons, sometimes as hair-like 'chalcotrichite'.
Photo: Didier Descouens, CC BY-SA 3.0
Iron oxide and the world's most important iron ore. It can be shiny steel-gray or earthy red, but always leaves a reddish streak.
Photo: Wikipedia Loves Art participant "Assignment_Houston_One", CC BY-SA 2.5
Quick tests
- Hardness: Hematite is clearly harder: Mohs 5.5–6.5 versus 3.5–4.
- Streak (rub on unglazed porcelain): Cuprite leaves a brownish red streak; Hematite leaves reddish brown.
- Luster: Hematite looks metallic; Cuprite doesn't.
Key differences
- Hematite is harder and not as red inside.
Side by side
| Property | Cuprite | Hematite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 3.5–4 | 5.5–6.5 |
| Luster | Adamantine to submetallic | Metallic to earthy |
| Streak | Brownish red | Reddish brown |
| Colors | Red, Black | Silver, Black, Red |
| Crystal system | Cubic | Trigonal |
| Specific gravity | 6.1–6.15 | 5.26 |
| Formula | Cu₂O | Fe₂O₃ |
| Found in | Onganja, Namibia; Bisbee, Arizona | Lake Superior iron ranges; Carajás, Brazil |
Properties that are the same for both are grayed out.
How to identify cuprite
- Deep red, glinting crystals that can look almost black.
- Heavy.
- Brownish-red streak.
Crystal system: Cubic
Full Cuprite guide →How to identify hematite
- Reddish-brown streak — the key test, even on silvery pieces.
- Heavy for its size.
- Not magnetic (or only weakly).
- Sometimes forms bubbly 'kidney ore' masses.
Crystal system: Trigonal
Full Hematite guide →More comparisons
Could you tell them apart from a blurry close-up?
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