RocksdayApatite vs Tourmaline
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 boron-bearing silicate found in more colors than almost any other gem. Black schorl is the most common form.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Quick tests
- Scratch glass: Tourmaline scratches glass (Mohs 7–7.5); Apatite can't (Mohs 5).
Key differences
- Tourmaline is harder and has a triangular, not hexagonal, cross-section.
Side by side
| Property | Apatite | Tourmaline |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 5 | 7–7.5 |
| Luster | Vitreous | Vitreous |
| Streak | White | White |
| Colors | Green, Blue, Yellow, Purple | Black, Green, Pink |
| Crystal system | Hexagonal | Trigonal |
| Specific gravity | 3.16–3.22 | 3–3.3 |
| Formula | Ca₅(PO₄)₃(F,Cl,OH) | Complex borosilicate |
| Found in | Durango, Mexico; Madagascar | Mount Mica, Maine; San Diego County, California |
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 tourmaline
- Long prisms with lengthwise grooves (striations).
- Rounded-triangle cross-section when broken across.
- Hard — scratches glass.
- Gem crystals can change color from end to end ('watermelon').
Crystal system: Trigonal
Full Tourmaline guide →More comparisons
Could you tell them apart from a blurry close-up?
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