Nephrite
Nephrite is a mineral composed of fibrous crystals, primarily actinolite, and is categorized along with jadeite as "jade." Because of its high toughness (resistance to breakage), it has been used for tools and ornaments since ancient times.
Nephrite with a dense texture derived from its fibrous structure
Basic Information
| English Name | Nephrite |
|---|---|
| Japanese Name | Nangyoku (Soft Jade) |
| Chemical Formula | Ca2(Mg,Fe)5(OH|Si4O11)2 |
| Crystal System | Monoclinic |
| Hardness | 6–6.5 |
| Specific Gravity | 2.96 |
| Transparency | Translucent to Opaque |
Features & Varieties
- Type of Jade: Unlike jadeite, it possesses high toughness due to its fibrous structure.
- Cat's Eye Effect: Specimens containing asbestos fibers exhibit a cat's eye effect (chatoyancy).
- Unique Texture: It has a greasy luster on the surface, which is distinct from a glassy luster.
Origin, Aliases, Treatments & Similar Stones
Representative Origins: Wyoming (snowflake variety), British Columbia (BC Jade), New Zealand, Taiwan, Australia, etc.
Aliases: Mutton-fat jade, etc. Pieces from the White Jade River in Hotan are considered the highest quality.
Treatments: May undergo wax impregnation or dyeing.
Similar Stones: Serpentine (softer; can be scratched with a needle)
Note: While tough, the surface can chip if struck hard, so handle with care.