RocksdayGalena vs Sphalerite
How to tell them apart
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
Zinc sulfide and the main ore of zinc. Its resinous, honey-to-black crystals can look metallic or almost gem-like.
Photo: Ivar Leidus, CC BY-SA 4.0
Quick tests
- Streak (rub on unglazed porcelain): Galena leaves a lead gray streak; Sphalerite leaves pale yellow to brown.
- Heft: Galena feels noticeably heavier for its size (specific gravity 7.4–7.6 vs 3.9–4.1).
- Luster: Galena looks metallic; Sphalerite doesn't.
Key differences
- Galena is silvery, truly metallic and much heavier; they often occur together.
Side by side
| Property | Galena | Sphalerite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 2.5–2.75 | 3.5–4 |
| Luster | Metallic | Resinous to adamantine |
| Streak | Lead gray | Pale yellow to brown |
| Colors | Silver, Gray | Brown, Black, Yellow, Red |
| Crystal system | Cubic | Cubic |
| Specific gravity | 7.4–7.6 | 3.9–4.1 |
| Formula | PbS | (Zn,Fe)S |
| Found in | Viburnum Trend, Missouri; Tri-State district, USA | Picos de Europa, Spain; Tri-State district, USA |
Properties that are the same for both are grayed out.
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 →How to identify sphalerite
- Resinous, 'tree-sap' luster.
- Six directions of cleavage — sparkly broken surfaces.
- Pale yellowish streak, even from black pieces.
- Smells of rotten eggs in hydrochloric acid.
Crystal system: Cubic
Full Sphalerite guide →More comparisons
Could you tell them apart from a blurry close-up?
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