RocksdayApatite vs Pyromorphite
How to tell them apart
A calcium phosphate group of minerals — the same family that makes up your teeth and bones.
Photo: Thomas Spann, CC BY 2.0
A lead phosphate forming bright green hexagonal barrels.
Photo: Ivar Leidus, CC BY-SA 4.0
Quick tests
- Heft: Pyromorphite feels noticeably heavier for its size (specific gravity 6.5–7.1 vs 3.16–3.22).
Key differences
- Apatite is much lighter and harder.
Side by side
| Property | Apatite | Pyromorphite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 5 | 3.5–4 |
| Luster | Vitreous | Resinous to adamantine |
| Streak | White | White |
| Colors | Green, Blue, Yellow, Purple | Green, Yellow, Brown |
| Crystal system | Hexagonal | Hexagonal |
| Specific gravity | 3.16–3.22 | 6.5–7.1 |
| Formula | Ca₅(PO₄)₃(F,Cl,OH) | Pb₅(PO₄)₃Cl |
| Found in | Durango, Mexico; Madagascar | Bunker Hill mine, Idaho; Les Farges, France |
Properties that are the same for both are grayed out.
How to identify apatite
- Six-sided prisms, often with flat ends.
- Hardness 5 — a knife just scratches it.
- Glassy, often yellow-green or neon blue.
- No obvious cleavage.
Crystal system: Hexagonal
Full Apatite guide →How to identify pyromorphite
- Grass-green to olive hexagonal prisms, often hollow-ended.
- Very heavy.
- Resinous luster.
Crystal system: Hexagonal
Full Pyromorphite guide →More comparisons
Could you tell them apart from a blurry close-up?
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