Nephrite
Last updated: April 2026
A variety of actinolite-tremolite, known for its toughness and greasy luster.
Nephrite has a specific gravity of 2.95 and a refractive index of 1.600–1.627, with a Mohs hardness of 6.0–6.5. It is aggregate.
Physical & Optical Properties
Measured with a polariscope, a refractometer, a hydrostatic balance, a Chelsea filter, a UV torch, a loupe, a darkfield loupe and a spectroscope — step-by-step for each.
Through the refractometer
Drawn from the refractive index above, on a 1.40–1.81 scale. How to take this reading.
Key Differentiators
- Fibrous, felted texture
- Lower SG than jadeite
- Extremely tough
Common Simulants
- Jadeite jade: Jadeite: RI 1.666; SG 3.34; higher luster (vitreous vs waxy); takes a higher polish.
- Serpentine: Serpentine: usually softer (3–6 Mohs, overlapping nephrite at the top of its range); SG 2.44–2.62, well below nephrite's 2.90–3.03; more waxy luster; low-hardness material scratches easily with a knife.
- Aventurine quartz: Aggregate DR; RI 1.544–1.553; SG 2.65; sparkly aventurescence; lighter feel.
Commonly Confused With
Commonly confused with: Jadeite, Serpentine, Aventurine Quartz, Amazonite, Aventurine, Prehnite.
Treatments
- Dyed (to intensify green)
- Wax or oil impregnation
Related Comparisons
Measurement Guides
Identifying a nephrite? Loupewise walks through these tests in order — RI, SG, fluorescence, and more.
Try Loupewise Free →Studying for the GIA, FGA, or FEEG practical? Nephrite is one of the 132 species in Loupewise’s drill and exam pool — practice identifying it from its measured properties under timed exam conditions.
Practice exams →