Key properties
| Chemical formula | Ca2(Mg,Fe)5Si8O22(OH)2 |
| Crystal system | Monoclinic |
| Mohs hardness | 6-6.5 |
| Toughness | Exceptional - the toughest gem material known, thanks to a felted interlocking fibrous structure; it outranks jadeite |
| Refractive index | 1.606-1.632 |
| Optic character | Aggregate (AGG); crystals are biaxial negative (-) |
| Specific gravity | 2.90-3.10 |
| Cleavage | Amphibole cleavage present in the fibres but not seen in the massive aggregate |
| Fracture | Splintery to granular, with a fibrous, woody look on broken surfaces |
| Habit | Massive, compact, felted masses of interlocking amphibole fibres; boulders and river-worn pebbles |
| Lustre | Dull to greasy; polish: Greasy to vitreous (the classic oily nephrite sheen) |
| UV fluorescence | Inert |
| Pleochroism | None (polycrystalline aggregate) |
| Cause of colour | Iron within the tremolite-actinolite series: more iron shifts the colour from white (tremolite) through green to black (ferro-actinolite) |
| Typical inclusions | Felted fibrous texture visible under magnification • black chromite or magnetite specks in some greens • no diagnostic single-crystal inclusions |
| Stability | Stable to light and wear • fuses slowly under a blowpipe or torch • warm acids slightly affect the surface |
| Heat sensitivity | Avoid torch work - the structure holds together but the surface will scorch and dull |
| Care and cleaning | Warm soapy water safe • ultrasonic generally safe • steamer safe for solid material • avoid strong acids and torch heat |
| Birthstones | No official birthstone; jade (both nephrite and jadeite) marks the 12th wedding anniversary |
| Availability | Plentiful - large boulder deposits support steady carving and bead supply |
| Recognition | Spot RI about 1.61 (range 1.606-1.632), SG about 2.95, greasy lustre, splintery fibrous fracture and exceptional toughness; spectrum usually featureless apart from a vague line near 500 nm |
Varieties (4)
Green Nephrite
| Colour | light to dark green, often mottled; spinach green is dark greyish green |
| Transparency | opaque |
| Clarity type | Polycrystalline; judge evenness and translucency |
| Phenomena | None |
| Appearance | Quiet, even green with an oily greasy glow; finest grades are translucent spinach to apple-toned green used for fine carving |
| Trade names | New Zealand greenstone / pounamu • spinach jade (dark greyish green) • BC jade (British Columbia) • Polar jade (bright northern BC material) |
| Misnomers | 'Canada jade' serpentine imitations • green dyed white nephrite sold as natural green |
| Typical sizes | Large boulders allow large carvings, bangles and beads |
| Cutting styles | Carvings • bangles • cabochons • beads • knife handles and inlay |
| Key separations | Vs jadeite: jadeite spot RI 1.66, SG 3.34, granular fracture, vitreous polish, often 437 nm line; nephrite 1.61 / 2.95 with greasy sheen and fibrous fracture • Vs serpentine: RI about 1.56, SG about 2.6, softer (scratches with steel) • Vs hydrogrossular: RI about 1.72 • Vs green prehnite: RI 1.62 but different texture • Vs maw sit sit: mixed chrome mineralogy, patchy |
| Sources (localities) | Canada (British Columbia - the principal modern source) • New Zealand (South Island pounamu) • China (Xinjiang Kunlun/Hetian) • Russia (Siberia, Baikal region) • USA (Wyoming, Alaska) • Australia (Cowell, South Australia) • Taiwan (Fengtian) • Poland (Jordanow) |
| Availability | Plentiful |
| Market notes | Sold by the piece and kilogram more than per carat; brightest translucent green (Polar jade class) commands premiums; Maori-design pounamu carries cultural provenance rules in New Zealand |
| Care notes | Warm soapy water; ultrasonic safe; robust in wear - the best everyday 'green stone' for bangles |
| In short | Green nephrite is the historic jade of China and New Zealand and today's carving workhorse from British Columbia. Its iron greens, greasy lustre and exceptional toughness suit bangles and carvings that outlast generations. |
| Size (ct) | USD per carat | Tier | As of |
|---|---|---|---|
| 1.00–20.00 | $2.00 – $30.00 | commercial | 2026-10-26 |
| 5.00–50.00 | $30.00 – $150.00 | fine translucent (Polar/Hetian class) | 2026-10-26 |
Retail market survey, per carat unless noted. Ranges describe what commercial to fine stones trade at; exceptional stones and provenance premiums sit above them.
Yellow-Brown Nephrite
| Colour | honey yellow to reddish brown and tan, often banded or mottled |
| Transparency | opaque |
| Clarity type | Polycrystalline |
| Phenomena | None |
| Appearance | Warm tawny browns and honey tones, often swirled or banded; popular for animal carvings and decorative pieces |
| Trade names | Honey jade (loose trade use) |
| Typical sizes | Large pieces available |
| Cutting styles | Carvings • cabochons • beads |
| Key separations | Vs yellow jadeite: jadeite spot RI 1.66 vs 1.61 • Vs yellow serpentine: RI about 1.56, softer • Vs stichtite-rich serpentine mixes: distinctive pink patches • Spot RI 1.61 and greasy feel identify nephrite |
| Sources (localities) | Canada (British Columbia) • New Zealand • China (Xinjiang) • Russia (Siberia, including 'golden' Siberian material) • USA (Wyoming) |
| Availability | Plentiful |
| Market notes | Decorative price level; golden Siberian nephrite with honey banding is the collector end |
| Care notes | Warm soapy water; robust |
| In short | Yellow-brown nephrite is weathered, iron-stained material in warm honey tones, used mainly for carvings. It shares the family's toughness and greasy lustre. |
| Size (ct) | USD per carat | Tier | As of |
|---|---|---|---|
| 1.00–20.00 | $2.00 – $20.00 | commercial | 2026-10-26 |
Retail market survey, per carat unless noted. Ranges describe what commercial to fine stones trade at; exceptional stones and provenance premiums sit above them.
White Nephrite (Mutton Fat)
| Colour | creamy translucent white to very light yellow, sometimes with faint mottling |
| Transparency | opaque |
| Clarity type | Polycrystalline |
| Phenomena | None |
| Appearance | Even, unctuous creamy white with a waxy-greasy translucency, like solidified tallow - the reference for the 'mutton fat' name |
| Trade names | Mutton fat jade • Hetian (Khotan) white jade • chicken bone jade (opaque chalky white, often simulated by burnt or dyed material) |
| Misnomers | Afghan 'white jade' and Russian whitened material sold as top Hetian mutton fat |
| Typical sizes | River pebbles usually small; mountain material larger |
| Cutting styles | Carvings • bangles • cabochons • pendants |
| Key separations | Vs white jadeite: jadeite spot RI 1.66 vs nephrite 1.61; jadeite SG 3.34 vs 2.95 • Vs white chalcedony: RI 1.54, vitreous-waxy • Vs howlite and magnesite: softer, SG about 2.5, matte • Translucent even white plus greasy feel and RI 1.61 confirm nephrite |
| Sources (localities) | China (Xinjiang, Hetian/Khotan - Yurungkash White Jade River, Kunlun range: the benchmark) • Russia (Baikal region) • Canada (British Columbia) • New Zealand |
| Availability | Fine Hetian mutton fat scarce and extremely prized in China; commercial white more available |
| Market notes | Top-grade Hetian mutton fat trades per gram in China at levels comparable to fine jadeite; provenance documentation is everything at the top end |
| Care notes | Warm soapy water; ultrasonic safe; no torch |
| In short | White nephrite, the famous mutton fat jade of Hetian, is near-pure tremolite with a tallow-like translucency. It is the most culturally loaded white ornamental stone in the Chinese market. |
| Size (ct) | USD per carat | Tier | As of |
|---|---|---|---|
| 1.00–10.00 | $5.00 – $60.00 | commercial white | 2026-10-26 |
| 1.00–10.00 | $100.00 – $1000.00 | fine Hetian mutton fat | 2026-10-26 |
Retail market survey, per carat unless noted. Ranges describe what commercial to fine stones trade at; exceptional stones and provenance premiums sit above them.
Black Nephrite
| Colour | black to very dark green-black |
| Transparency | opaque |
| Clarity type | Polycrystalline |
| Phenomena | None |
| Appearance | Deep uniform black with a slightly oily polish; robust and masculine in feel, popular for men's bangles and carvings |
| Trade names | Black jade (nephrite) • Karakash (Black Jade) river material, Xinjiang |
| Misnomers | Dyed black chalcedony, black serpentine and basalt sold as 'black jade' |
| Typical sizes | Large pieces common |
| Cutting styles | Bangles • cabochons • carvings • men's jewellery |
| Key separations | Vs black jadeite: jadeite spot RI 1.66 vs 1.61, SG 3.34 vs 2.95, vitreous vs greasy polish • Vs black onyx (dyed chalcedony): spot RI 1.54 • Vs black obsidian: glassy conchoidal fracture, RI about 1.50 • Vs black serpentine: RI about 1.56, much softer, waxy |
| Sources (localities) | China (Xinjiang, Karakash river area) • Canada (British Columbia) • Australia (Cowell) • Russia • USA (Wyoming) |
| Availability | Plentiful |
| Market notes | Modest, stable pricing; verify species because true black nephrite is frequently imitated by dyed chalcedony |
| Care notes | Warm soapy water; ultrasonic safe; very robust in wear |
| In short | Black nephrite is the iron-rich, nearly opaque end of the amphibole jades, taking a soft oily black polish. Tougher and more wearable than most black ornamental stones, it anchors men's jade jewellery. |
| Size (ct) | USD per carat | Tier | As of |
|---|---|---|---|
| 1.00–20.00 | $3.00 – $25.00 | commercial | 2026-10-26 |
Retail market survey, per carat unless noted. Ranges describe what commercial to fine stones trade at; exceptional stones and provenance premiums sit above them.
Sources
GIA gem encyclopedia · mindat.org · Wikipedia
Data compiled and fact-checked against gemmological literature, October 2026 (JDMIS gem reference). Properties are ranges accepted in gemmological practice; individual stones vary.
See also
Gemstone reference entries: gem #90 · gem #129 · gem #179 · gem #205
Related materials: Jadeite
Identification wizard · All 83 materials · Singapore gem labs