RocksdayChabazite vs Fluorite
How to tell them apart
A zeolite whose rhombohedral crystals look almost like little cubes.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
A colorful mineral that grows as cubes and splits into octahedrons. Many specimens glow under ultraviolet light — the word 'fluorescence' was coined from it.
Photo: CarlesMillan, CC BY-SA 3.0
Quick tests
- Heft: Fluorite feels noticeably heavier for its size (specific gravity 3.18 vs 2.05–2.2).
Key differences
- Fluorite is heavier and cleaves into octahedrons.
Side by side
| Property | Chabazite | Fluorite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 4–5 | 4 |
| Luster | Vitreous | Vitreous |
| Streak | White | White |
| Colors | White, Orange, Pink, Clear | Purple, Green, Blue, Yellow, Clear |
| Crystal system | Trigonal | Cubic |
| Specific gravity | 2.05–2.2 | 3.18 |
| Formula | (Ca,Na₂,K₂,Mg)Al₂Si₄O₁₂·6H₂O | CaF₂ |
| Found in | Nova Scotia; Oregon | Cave-in-Rock, Illinois; Weardale, England |
Properties that are the same for both are grayed out.
How to identify chabazite
- Nearly cubic crystals in basalt cavities.
- Clear to peach.
- Doesn't fizz in acid.
Crystal system: Trigonal
Full Chabazite guide →How to identify fluorite
- Cubic crystals, often with color zoning in purple and green.
- Cleaves into eight-sided octahedral fragments.
- Hardness 4 — a knife scratches it, but a coin doesn't.
- Often glows blue or violet under a UV flashlight.
Crystal system: Cubic
Full Fluorite guide →More comparisons
Could you tell them apart from a blurry close-up?
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