RocksdayAcanthite vs Galena
How to tell them apart
Silver sulfide and the most important silver ore — a soft, black, sectile mineral.
Photo: Ivar Leidus, CC BY-SA 4.0
Lead sulfide and the world's main lead ore. Bright silvery cubes that feel astonishingly heavy for their size.
Photo: Ivar Leidus, CC BY-SA 4.0
Quick tests
- Streak (rub on unglazed porcelain): Acanthite leaves a black streak; Galena leaves lead gray.
Key differences
- Galena is brighter and cleaves into cubes.
Side by side
| Property | Acanthite | Galena |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 2–2.5 | 2.5–2.75 |
| Luster | Metallic | Metallic |
| Streak | Black | Lead gray |
| Colors | Black, Gray | Silver, Gray |
| Crystal system | Monoclinic | Cubic |
| Specific gravity | 7.2–7.4 | 7.4–7.6 |
| Formula | Ag₂S | PbS |
| Found in | Guanajuato, Mexico; Freiberg, Germany | Viburnum Trend, Missouri; Tri-State district, USA |
Properties that are the same for both are grayed out.
How to identify acanthite
- Black to lead-gray, dull metallic.
- Cuts like lead with a knife.
- Very heavy.
Crystal system: Monoclinic
Full Acanthite guide →How to identify galena
- Very heavy — noticeably heavier than any similar-sized rock.
- Bright silver-gray metallic, dulling over time.
- Breaks into perfect little cubes.
- Soft enough to scratch with a fingernail edge or coin.
Crystal system: Cubic
Full Galena guide →More comparisons
Could you tell them apart from a blurry close-up?
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