RocksdayHornblende vs Wolframite
How to tell them apart
A common black amphibole and the dark specks in many granites and diorites.
Photo: Shannon Heinle, CC0
An iron manganese tungstate and a major ore of tungsten — black, flat and very heavy.
Photo: Didier Descouens, CC BY-SA 4.0
Quick tests
- Streak (rub on unglazed porcelain): Hornblende leaves a gray-green streak; Wolframite leaves reddish brown to black.
- Heft: Wolframite feels noticeably heavier for its size (specific gravity 7–7.5 vs 3–3.4).
Key differences
- Hornblende is much lighter.
Side by side
| Property | Hornblende | Wolframite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 5–6 | 4–4.5 |
| Luster | Vitreous | Submetallic |
| Streak | Gray-green | Reddish brown to black |
| Colors | Black, Green, Brown | Black, Brown |
| Crystal system | Monoclinic | Monoclinic |
| Specific gravity | 3–3.4 | 7–7.5 |
| Formula | Ca₂(Mg,Fe,Al)₅(Al,Si)₈O₂₂(OH)₂ | (Fe,Mn)WO₄ |
| Found in | Granites and diorites worldwide; Amphibolites | Panasqueira, Portugal; Jiangxi, China |
Properties that are the same for both are grayed out.
How to identify hornblende
- Black to dark green elongated prisms.
- Two cleavages meeting at about 56° and 124°.
- Shiny, splintery breaks.
Crystal system: Monoclinic
Full Hornblende guide →How to identify wolframite
- Black bladed crystals with one perfect, shiny cleavage.
- Extremely heavy for its size.
- Often with quartz and cassiterite.
Crystal system: Monoclinic
Full Wolframite guide →More comparisons
Could you tell them apart from a blurry close-up?
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