Does jade change color over time?

Does jade change color? Good untreated jade does not. Its body color stays the same through wear, light and time, and GIA describes jade as stable to light. What changes is the surface of the piece and the light you see it in. There are two real exceptions: cheap, coarse-grained jadeite can slowly turn yellowish or dirty-looking, and treated jade can fade or discolor.

What you notice	Likely cause	What it means
Glossier, with color showing a little better, after months of wear	Skin oil on the surface	Harmless, and it washes off
Coarse-grained jadeite slowly going yellowish or grayish	The discoloring the trade calls bian zhong	Permanent, and not a sign of a fake
Dark lines along cracks	Dirt, sweat and oil taken into open cracks	The stone itself may be sound
Vivid green or lavender growing paler	Dye fading	The piece is dyed
Color coming off on skin or a tissue	Tinted polishing powder on the surface	Surface coloring
A different color at home than in the shop	Lighting, setting or backing	No change in the stone

Does jade get greener the longer you wear it?

The belief is old and widely repeated. A saying heard throughout the Chinese jade trade, ren yang yu, yu yang ren (人养玉, 玉养人), means that the person nourishes the jade and the jade nourishes the person. It is the source of the idea that jade improves, or turns greener, the longer it is worn. The gemologist Richard Hughes and his co-authors record a related piece of folklore in their Gems & Gemology study of the jade trade: a spot of fine color in a bangle may spread across the whole stone, depending on the good fortune of the wearer, and an ornament that turns dull foretells bad luck.

That is belief. Dealers who address the claim directly agree on one thing: the green itself does not grow or spread.

Where they differ is on whether wear improves a piece at all. Some say oil from the skin makes the surface glossier and, over time, slightly more translucent, so the color that was already there shows more clearly. Others call the whole idea a sales line. In their account the gloss is a film of oil on the surface, and washing the piece returns it to how it looked before.

Two things about the surface are not in dispute:

• Wax. Waxing is the final step in finishing virtually all cut jadeite. It improves luster and fills surface pits and fine fractures, and a wax-finished stone still counts as untreated. Wax is a surface finish, and a surface finish is unlikely to stay as it was through years of wear, which is one reason an old piece can look different from a new one.
• Nephrite and handling. Fine-grained nephrite becomes glossier with handling, which collectors value. Dealers warn that coarse-grained nephrite does not improve this way. It just gets dirty.

When jadeite really does discolor

Jadeite with coarse, loosely packed grains can slowly discolor in wear, turning yellowish, grayish or dirty-looking. The Chinese trade calls this bian zhong (变种). It happens to genuine untreated jadeite and is not a sign of a fake.

Which stones are at risk

The stones at risk are those in which you can see the grain with the naked eye:

• bean-type jadeite, dou zhong (豆种)
• coarse, milky material
• stone with a “crushed ice” look

Jadeite with fine, tight texture, where no grain is visible, essentially does not discolor this way. Dealers single out one further type: the gray-blue “oily green” jadeite called you qing (油青), which they describe as prone to discoloring even when its texture looks reasonably fine.

Cracks are a separate problem. Open cracks and veins take in dirt, sweat and oil over time and darken along their length, so a piece with cracks that reach the surface will look worse with wear even if the stone itself is sound.

How long it takes

Dealers give different timescales, from two or three years for the cheapest coarse bangles to five to ten years for better ones. Treat these as trade experience, not measurements.

Why it happens

Dealers do not agree on the cause. Three explanations circulate:

1. Skin oil and sweat seep into the gaps between grains and oxidize there.
2. The stone oxidizes on contact with air whether or not it is worn. Dealers who hold this view show unworn stock that has already started to yellow.
3. The yellowing is like rusting, with iron in the stone slowly oxidizing.

No one disputes the outcome. The discoloration is permanent. It runs through the stone, not just the surface, so repolishing does not remove it.

Color change as a sign of treatment

A color that fades, turns blotchy or rubs off points to treatment.

Dye. Hughes and his co-authors saw fading in dyed green and dyed lavender jadeite and found that green dyes fade more readily. Dye concentrates in cracks and along grain boundaries, so look there for uneven color.

Bleached and polymer-filled jade. B jade is made by removing brown or gray staining with chemicals and then filling the stone with polymer, a process documented in a GIA study. The American Gem Trade Association says B and C jade are significantly more brittle than natural jade and can change color if the dye fades or if the polymers or acids release from the stone. It puts the value of B jade at roughly 5 to 10 percent of a natural stone that looks the same. Only infrared spectroscopy gives conclusive evidence of the polymer, which means a laboratory. The grades are explained in type A, B and C jade, and why treated jade breaks more easily in jade hardness and toughness.

Tinted polishing powder. Color applied this way sits on the surface. It wears off within months of use and can stain the skin. Wipe a small spot of the colored area with alcohol on a tissue: if the tissue picks up color, the color was on the stone and not in it. Treat this as a one-off check, not a way to clean jade: solvents also strip the wax finish (see how to clean jade).

Changes that are only in the light

Much apparent color change is a change of light. Pale lavender jade can look clearly purple under shop lighting and nearly white in daylight, and GIA notes that professional buyers judge jade color under more than one light source.

Translucent jade also takes on color from what is around and behind it. A small green vein can make a whole white cabochon look green when it is lit from behind, and a double-domed cut intensifies color. A yellow gold backing or a warm lamp adds a yellowish tone to green that disappears in overcast daylight.

What to do if your jade has changed color

1. Clean it. Warm, soapy water is always safe for jade. GIA says ultrasonic and steam cleaners are safe only for untreated jade, and since treatment is common it advises the soapy-water method. Step-by-step care is in how to clean jade.
2. Look again in daylight. Compare it with how you remember it, away from lamps and off any colored surface.
3. Get it tested if it matters. Where the change sits, as in the table above, narrows things down. For anything valuable, a gemological laboratory report is the only thing that settles whether a piece is treated.

One last point on the saying. The half about jade nourishing the person is a belief about health and luck. There is no scientific evidence that stones worn on the body have healing effects: in a controlled test reported by Live Science, people described the same sensations whether they held a real crystal or a fake one. The traditional claims are set against the evidence in jade stone benefits.