Jade — Two Stones, One Legendary Story
Jade isn’t one mineral—it’s a duet. Jadeite (a sodium‑aluminum pyroxene) and nephrite (a tremolite‑actinolite amphibole) look like close cousins but build themselves differently. Jadeite is a sugar‑fine mosaic of grains; nephrite is a mat of interlocking fibers. Both are famously tough, which is why cultures across the world carved jade into tools, ritual objects, talismans, and wearable art. Same name, two architectures—and a very long human friendship. (Also: yes, it feels cool to the touch. That’s part of the charm.)
Identity & Naming 🔎
Two species under one cultural name
Across East Asia, “yu” historically referred to nephrite. In later centuries, fei cui (翡翠) distinguished jadeite, especially the bright, translucent greens. In the West, “jade” is the umbrella for both.
The feel of jade
Jade’s reputation for toughness comes from its microstructure: jadeite’s tight, interlocking grains resist crack travel; nephrite’s felted fibers deflect and blunt cracks. That’s why thin bangles and intricate carvings are possible.
Jadeite vs. Nephrite — Quick Comparison 🧭
| Feature | Jadeite | Nephrite |
|---|---|---|
| Mineral family | Pyroxene (NaAlSi2O6) | Amphibole (tremolite–actinolite series) |
| Microstructure | Fine, interlocking granular mosaic (“sugar” texture) | Interwoven, fibrous (“felted”) texture |
| Typical RI (spot) | ~1.66–1.67 | ~1.61 |
| Specific gravity | ~3.30–3.38 (heftier) | ~2.95–3.10 |
| Hardness (Mohs) | ~6.5–7 | ~6–6.5 |
| Colors | Broad palette: emerald/“imperial” green (Cr), apple, lavender (Mn), icy colorless, yellow, red‑orange, black | Greens (iron), creamy white “mutton fat,” spinach, yellowish, brown to near‑black |
| Translucency | From opaque to highly translucent (“icy”); even texture reads like misted glass | Usually translucent‑opaque; fine white shows a buttery glow |
| Treatments & trade types | Common types: Type A (natural; surface wax OK), Type B (bleached + polymer), Type C (dyed), B+C (both) | Occasional dye/polymer impregnation; many pieces are simply waxed/polished |
Palette & Texture Vocabulary 🎨
Color swatches
- Vivid green — chromium‑bearing jadeite (“kingfisher,” “imperial”).
- Icy — colorless to pale, high‑translucency jadeite.
- Lavender — jadeite with Mn tint; soft lilac to richer violet.
- Mutton fat — fine white nephrite with creamy, even glow.
- Spinach — dark, iron‑rich nephrite.
Lighting matters: cool daylight leans greens cooler; warm light lends honey and cream to whites and pale tones.
Texture words
- Glassy‑mist (jadeite) — fine grains vanish to a smooth inner glow.
- Buttery (nephrite) — soft, waxy lustre with felted micro‑texture.
- Clouds & moss — wispy tonal patches or streaks, often in nephrite.
- Ice & fissures — natural internal lines in translucent jadeite, not surface cracks.
Photo tip: Use a diffused key light and a small backlight at ~30°. Jade likes soft illumination that shows translucency without glare.
How They Form 🧪🌋
Jadeite
Forms in high‑pressure, low‑temperature metamorphic settings (subduction zones). Fluids move sodium and aluminum; pyroxene crystallizes as jadeite masses and veins. Later tectonics bring those rocks up where humans can find them.
Nephrite
Forms where calcium‑magnesium silicates metamorphose and serpentinize. Actinolite/tremolite fibers grow and interlock into tough, felted aggregates—nature’s green felt.
Why the toughness
The key is interlocking microstructure. In both jades, cracks must zigzag through grains or fibers, dissipating energy. That’s why thin bangles survive everyday life.
Physical & Optical Details 📐
| Property | Jadeite | Nephrite |
|---|---|---|
| Chemistry | NaAlSi2O6 (with solid solution) | Ca2(Mg,Fe)5Si8O22(OH)2 |
| Crystal system | Monoclinic (pyroxene) | Monoclinic (amphibole) |
| Hardness | ~6.5–7 | ~6–6.5 |
| Specific gravity | ~3.30–3.38 | ~2.95–3.10 |
| Refractive index (spot) | ~1.66–1.67 | ~1.61 |
| Luster | Vitreous to waxy | Waxy to silky |
| Cleavage | Poor, not obvious in fine‑grained masses | Indistinct in felted aggregates |
| Toughness | Excellent | Exceptional (among the highest in gem materials) |
| Typical treatments | Type A/B/C system (see below) | Waxing; occasional polymer/dye |
Under the Loupe 🔬
Jadeite “sugar”
At 10×, jadeite shows a granular mosaic—tiny grains that meet at curving boundaries. In translucent pieces, look for “cotton” wisps and delicate growth streaks.
Nephrite “felt”
Nephrite shows fibrous/felted structure. Under raking light, the polish looks soft and waxy; thin edges glow buttery rather than glassy.
Treatment clues
Polymer: glassy shine that looks “wet” in fissures; air bubbles in filled cracks under high mag. Dye: intense color concentrating along grain boundaries and fractures; uneven halos.
Look‑Alikes & Misnomers 🕵️
Serpentine (“new jade”)
Softer (often ~3–5), greasy luster, lower heft; scratches more readily. Common decorative stone with jade‑like greens.
Aventurine quartz
Green quartz with mica sparkles (aventurescence); much harder (7), glittery under light, different feel.
Hydrogrossular (“Transvaal jade”)
A green garnet variety; granular, different RI/SG; trade name is a misnomer—beautiful but not jade.
Chrysoprase / prehnite
Apple‑green chalcedony (Ni‑colored) or prehnite (phyllosilicate). Both have different translucency & luster fingerprints.
Glass & polymers
Too even in color, rounded “orange‑peel” bubbles, and a warm feel in hand. Heft and loupe work expose the ruse quickly.
Maw‑sit‑sit
Jade‑related rock from Myanmar (kosmochlor‑rich) with bright green/black patchwork. Historically used alongside jade but compositionally different.
Localities & Traditions 📍
Where jadeite & nephrite turn up
- Jadeite: Myanmar (classic bright greens & lavenders), Guatemala, Mexico, Japan, Kazakhstan, Russia.
- Nephrite: China (Hetian/Hotan “mutton fat”), New Zealand (pounamu/greenstone), British Columbia (Canada), Siberia, Taiwan, Wyoming.
Each region carries its own carving traditions—tools, motifs, and surface finishes that are a joy to compare.
Carving heritage
Jade has been shaped into ritual objects, ornaments, blades, seals, pendants, and bangles for millennia—from Neolithic China and Mesoamerica’s jadeite masterpieces to Māori hei tiki carved in nephrite.
Care & Studio Notes 🧼🛠️
Everyday care
- Mild soap and lukewarm water; soft cloth; dry well.
- Avoid acids, harsh detergents, ultrasonics & steam—especially for Type B/C jadeite or dyed nephrite.
- Store separately; jade is tough but edges can still scuff against corundum/diamond neighbors.
Jewelry guidance
- Wonderful as bangles, cabochons, beads, and carvings. Toughness suits everyday wear; mind sudden shocks on thin bangles.
- Open backs and soft lighting show off translucency; white metals cool greens, yellow metals add warmth.
- For strands, knot between beads—classic look and extra safety.
On the wheel (lapidary)
- Cut cool with light pressure; jade can orange‑peel if over‑heated or rushed.
- Pre‑polish thoroughly (600→1200→3k); finish with alumina or chrome oxide on leather/felt for a deep waxy glow.
- Orient to minimize stress across thin sections (especially bangles and plaques).
Questions ❓
Is all green “jade” the same?
No. Some is jadeite, some is nephrite, and some is not jade at all (serpentine, glass, hydrogrossular). The differences are testable and worth naming clearly.
What does “Type A/B/C” mean?
A shorthand for jadeite’s treatment status: Type A natural (waxed is fine); Type B bleached + polymer; Type C dyed; B+C both. Nephrite isn’t usually described this way but may be dyed or polymer‑treated; disclosure helps everyone.
Why does jade feel cool?
It has decent thermal conductivity for a gem; it draws heat from your skin faster than many materials, so it starts out cool to the touch.
Can jade change color?
Natural color is stable. Dyed/bleached pieces can shift with solvents, heat, or time. That’s another reason to know the treatment story.
How do I tell jadeite from nephrite at home?
Weight (jadeite is heftier), magnification (granular vs. felted texture), and a bright light for translucency clues. Definitive IDs use instruments (RI, SG, spectroscopy).