JewelryWiki
The Encyclopedia of AdornmentEst. 2026Every value cited
AboutContactEN

Nephrite

NephriteJewelryWiki Editorial·4 sources·Reviewed 2026-08-04
Nephrite specimen
Nephrite specimen. Piotr Sosnowski, CC BY-SA 4.0 · Wikimedia Commons

The other jade. Softer than jadeite and generally less valuable, but similarly tough.

Properties

PropertyValueAuthority
Mohs hardness6–6½ [1]
Refractive index1.600–1.627 [1]
Specific gravity2.90–3.03 [1]
Chemical formulaCa2(Mg,Fe2+)5Si8O22(OH)2 Nephrite is a rock name for the massive, interlocking-fibre form of the tremolite–actinolite amphibole series, not a mineral name. This is tremolite, the magnesium end; increasing iron moves the same material toward actinolite and darkens it. [4]
Crystal systemMonoclinic [2]
Read from the species article, Actinolite.
Common treatmentsListed by GIA among the materials dyed since ancient times, and among the opaque materials impregnated with wax or plastic to improve durability and appearance. [3]
Care cautionsIf dyed, avoid acetone, alcohol and prolonged sunlight. If impregnated, avoid heat. [3]

Sources

  1. International Gem Society — reference charts (Mohs hardness, specific gravity, refractive index) — International Gem Society (IGS reference charts)
  2. Wikipedia — mineral article infoboxes (crystal system) — Wikipedia contributors (Wikipedia mineral infoboxes)
  3. GIA — An Introduction to Gem Treatments — Gemological Institute of America (GIA, An Introduction to Gem Treatments (Robert Weldon))
  4. Handbook of Mineralogy — Mineral Data Publishing / Mineralogical Society of America (Handbook of Mineralogy, Mineral Data Publishing)