RocksdayNatrolite vs Okenite
How to tell them apart
A zeolite forming glassy, needle-like crystals in sprays.
Photo: Didier Descouens, CC BY-SA 4.0
Puffballs of fine white fibers that look like cotton or snowballs inside basalt cavities.
Photo: Kora27, CC BY-SA 4.0
Key differences
- Okenite is soft and fluffy.
Side by side
| Property | Natrolite | Okenite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 5–5.5 | 4.5–5 |
| Luster | Vitreous to silky | Silky |
| Streak | White | White |
| Colors | White, Clear | White |
| Crystal system | Orthorhombic | Triclinic |
| Specific gravity | 2.2–2.26 | 2.28–2.33 |
| Formula | Na₂Al₂Si₃O₁₀·2H₂O | CaSi₂O₄(OH)₂·H₂O |
| Found in | New Jersey; Kola Peninsula, Russia | Pune, India; Greenland |
Properties that are the same for both are grayed out.
How to identify natrolite
- Clear to white needles in radiating sprays.
- Square cross-section on larger crystals.
- Light and brittle.
Crystal system: Orthorhombic
Full Natrolite guide →How to identify okenite
- Fluffy white fiber balls, soft to the eye.
- Fibers flatten when touched — handle by the matrix.
- Often with green apophyllite or quartz.
Crystal system: Triclinic
Full Okenite guide →More comparisons
Could you tell them apart from a blurry close-up?
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