RocksdayNephrite vs Serpentinite
How to tell them apart
The other jade: a dense mat of interlocking amphibole fibers that makes one of the toughest natural materials.
Photo: Piotr Sosnowski, CC BY-SA 4.0
Rock of serpentine minerals, formed when mantle rock reacts with seawater. Slick, green and mottled.
Photo: Gabriel HM, CC BY-SA 4.0
Quick tests
- Scratch glass: Nephrite scratches glass (Mohs 6–6.5); Serpentinite can't (Mohs 3–5).
- Texture: Serpentinite is a rock — a mix of grains or minerals; Nephrite is a single mineral.
Key differences
- Nephrite is much tougher and harder.
Side by side
| Property | Nephrite | Serpentinite |
|---|---|---|
| Type | Mineral | Metamorphic rock |
| Mohs hardness | 6–6.5 | 3–5 |
| Luster | Greasy to waxy | Waxy to greasy |
| Streak | White | — |
| Colors | Green, White, Black | Green, Black |
| Crystal system / structure | Monoclinic (fibrous) | Massive, often sheared |
| Specific gravity | 2.9–3.03 | 2.5–2.8 |
| Formula | Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂ | — |
| Found in | British Columbia, Canada; Hotan, Xinjiang, China | California Coast Ranges; Newfoundland |
Properties that are the same for both are grayed out.
How to identify nephrite
- Extremely tough, with an oily, waxy polish.
- Spinach to olive green, creamy white or black.
- Often found as smooth river boulders.
Crystal system: Monoclinic (fibrous)
Full Nephrite guide →How to identify serpentinite
- Green to black with a waxy, slippery look.
- Polished, scaly surfaces where it was sheared.
- Softer than it looks.
Structure: Massive, often sheared
Full Serpentinite guide →More comparisons
Could you tell them apart from a blurry close-up?
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