By The Eye desk · Last verified 29 September 2026

In the jade trade, “Type A”, “Type B” and “Type C” describe whether jadeite has been treated. Type A is natural, apart from traditional cleaning and waxing. Type B has been bleached with acid to remove stains and then filled with polymer resin to improve its translucency. Type C has been dyed to add or strengthen its colour. Type B+C is both. Treated jade can look as good as, or better than, natural jade, and even experts often can’t tell by eye, so for a valuable piece a laboratory report is the only reliable proof.

Quick facts

• Type A: natural jadeite; wax polishing is allowed.
• Type B: acid-bleached and polymer-impregnated.
• Type C: dyed; the colour can fade.
• Type B+C: bleached, filled and dyed.
• These are trade terms for treatment, not quality grades.
• Labs detect treatments with instruments, not by eye.

What does each type mean?

Type	Treatment	What happens over time
A	None, beyond traditional cleaning and wax polishing	Stable
B	Soaked in acid to remove stains, then impregnated with polymer resin	The polymer can break down with heat and household detergents, and the stone can lose its lustre
C	Dyed to add or deepen colour	The colour can fade or change with heat, chemicals or sunlight
B+C	Bleached, filled and dyed	Worth a fraction of what it appears

Why does treatment matter?

Because it changes both value and durability. Bleaching loosens the interlocking crystal structure that makes jadeite tough, which is why Type B needs polymer to hold it together. It can make low-grade, opaque jade look like fine translucent jade, at a small fraction of the price.

How can I tell?

Mostly, you can’t, by eye. Standard tests of weight and refraction are often inconclusive. Laboratories use instruments such as infrared spectroscopy to detect polymer and other methods to detect dye. For anything costly, ask for a report from an independent gemmological laboratory, and ask the seller in writing whether the piece is Type A.

The WahLiao Verdict

If a translucent green bangle is cheap, assume it’s treated. Buy costly jade only with an independent lab report stating Type A, and treat a price that’s too good as the best clue you’ll get.

Questions people ask

Is Type B still real jade?

Yes, it’s jadeite, but chemically treated, and worth much less than natural Type A.

Is waxing a treatment?

Traditional wax polishing is accepted as part of finishing and doesn’t change a piece from Type A.

What’s the difference between jadeite and nephrite?

They’re two different minerals both called jade. Jadeite, mainly from Myanmar, is the one the A, B and C terms describe.

Can a jade be glass?

Yes. Glass, plastic and resin imitations exist; they’re not jade at all.

Sources: Jewellery Business on identifying Type A, B and C; H&F Jewellery on the trade definitions; Contract Laboratory on jade testing; Mason-Kay on why testing by eye fails.

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