The short answer

B changes the clarity. C changes the color.

Type B is jadeite that was bleached and then filled with clear resin to make it look clearer. Type C is jadeite that was dyed to make it look greener or more colorful. Type B + C is both done to the same stone.

Neither one is the same as Type A. Type A has had nothing added and nothing taken out — it was only cut and polished. A light wax after polishing is normal finishing and still counts as Type A.

One more thing worth saying right away: these letters describe what was done to the stone, not how pretty it is. A pale, cloudy Type A stone can be worth less than a nice-looking treated piece. What the letter tells you is whether the stone is natural.

Those value ranges are rough trade rules of thumb, not official grades. Jadeite is priced piece by piece, so a good treated stone can beat a poor natural one.

Type B

Bleached, then filled with polymer.

Type B is a two-step treatment, and both steps matter.

Step one is bleaching. The stone is soaked in acid to dissolve out the brown and grey discoloration sitting in the grain. It works, but it also eats into the structure and leaves the stone porous and weak.

Step two is the fill. The stone is then soaked in clear resin or polymer, which seeps into those pores and brings back the transparency the acid removed. That resin soak is called polymer impregnation, and it is the defining step of Type B. It is what separates Type B from a stone that was merely cleaned.

The result looks cleaner than the original rough ever could. Its color is genuinely its own. Its clarity has been engineered.

What the acid and resin actually change

• The grain is loosened. Bleaching dissolves some of the natural cement between the crystals, so the stone is more open and more porous than before.
• The weight can drop slightly. Resin is lighter than jadeite, so a filled stone often reads a touch under the natural 3.34 specific gravity.
• The clarity is borrowed, not grown. The resin does not rebuild the interlocking crystal structure. It fills the gaps and masks them.
• The filler is not one fixed recipe. Wax, resin, and other polymers are all used, and each leaves a different fingerprint under a lab instrument.

That engineering is also the weakness. The resin is softer than jadeite, and over years it can yellow, cloud, shrink, or leach out of exposed fractures. Heat, steam, solvents, ultrasonic cleaners, and some repair work can damage it further. A Type B stone is not a lifetime purchase in the way a Type A stone is.

Type C

Color added with dye.

Type C is about color only. Dye is put into the stone to make it green, lavender, or yellow when nature did not.

No bleaching is required. The mineral structure is often left intact. It is simply wearing a color it did not grow.

Because dye is pushed in from the outside, it tends to gather where the stone is most open: along cracks, along grain boundaries, and near the surface. Under strong light that shows up as darker lines of color in the fissures, or as flat, even brightness with no depth behind it.

Dye also fades. Sunlight, heat, solvents, and ordinary wear can pull the color out or make it patchy over time, exposing the pale stone underneath.

Where dye hides

• In the cracks. Color that looks like a thin green line trapped in a fracture is a classic sign.
• On the surface. Dyed stones can look bright right at the skin and pale deeper in.
• In the grain lines. Dye seeps between crystals, so the color can look painted on rather than growing from inside.

None of those are proof on their own. A photo cannot settle it, and neither can a quick look with a loupe. Only a laboratory report can.

The combination

Type B + C is both, stacked.

Bleach and fill first, dye on top. False clarity and false color on the same stone. Gemological laboratories recognize B and C treatment on a single piece and report it as B + C.

It is the lowest of the treated categories, and in some ways the easiest to spot: dye pooling along the cracks and grain lines of a stone that was already weakened to begin with.

Side by side

How it is caught

You cannot see polymer. A laboratory can.

This is the part most buyers never hear. The treatment is designed to be invisible, and on a well-treated stone it usually is.

Refractive index stays close to normal jadeite either way, so a refractometer alone will not flag Type B. Specific gravity often dips slightly because the resin is lighter than the stone it replaced, but the shift is small enough to overlap natural readings. Neither test is a verdict on its own.

The decisive test is infrared spectroscopy, usually written FTIR. Organic resin and wax absorb infrared light at wavelengths that natural jadeite does not, so the instrument can see the filler inside the stone even when your eye cannot. Laboratories pair that with magnification to look for filled fractures and dye pooled in fissures, and with UV-visible spectroscopy for color origin.

The tests labs actually run

A serious lab does not rely on one test. It combines mineral identification, a microscope look, infrared for the filler, UV-visible for the color, and elemental analysis when the color is unclear.

That is why a certificate carries more weight than any photograph, and why a seller calling a stone natural is not the same as a laboratory confirming it.

The money

What treatment does to the price.

Type A jadeite can sell for many times the price of a similar-looking Type B or C piece. There is no official percentage table, because jadeite is priced one piece at a time by color, translucency, texture, size, cut, and certificate. But the trade discount is large and fairly consistent in direction.

• Type B commonly trades around 5–30% of a comparable untreated piece.
• Type C commonly trades around 1–10%.
• Type B + C is usually the deepest discount, around 1–5%.

Put simply: if a fair Type A piece is $10,000, a similar Type B stone might be $500–$3,000 and a Type C stone might be $100–$1,000. Those numbers are illustrations, not appraisals.

The real problem is not treated jade. It is treated jade sold at Type A money. That is where buyers lose the most, and it is the most common way people overpay in this market.

Durability

How each one ages.

Treatment is not just a price question. It changes what the piece will look like in ten years.

Type A

Untreated jadeite is the most stable. It is tough because its crystals interlock, which is why jade survived generations and was used for tools long before jewelry. It can still chip or crack, especially at thin edges, but it has no filler to break down and no dye to fade.

Type B

Bleaching weakens the grain, and the resin can shrink, yellow, cloud, or come loose from the cracks over time. Heat, steam, harsh cleaners, and ultrasonic machines can make it worse. Many jewelers will not put a Type B piece in an ultrasonic tank at all.

Type C

Dye can fade in sunlight, shift with heat, or creep into cracks. A dyed stone that looked vivid at purchase can look patchy and pale years later.

A treated stone can look wonderful on the day you buy it. The question is what it looks like later.

The rules

Sellers are supposed to tell you.

In the United States, the FTC jewelry guides say a treatment has to be disclosed when it is not permanent, when it needs special care, or when it changes the value in a meaningful way. Bleaching, resin filling, and dyeing all hit those points.

That means “natural jade,” “untreated,” or “Type A” should never be used for a stone that was bleached, filled, or dyed. A correct description reads more like “jadeite, bleached and polymer impregnated — Type B” or “dyed jadeite — Type C.”

If a seller will not put the treatment in writing on the receipt, that is your answer. A real certificate names the stone and says plainly whether it is untreated, filled, dyed, or both.

Before you buy

Five questions that settle it.

• “Is this Type A, and is that on the certificate?” Not the listing — the certificate.
• “Which lab issued the report, and what is the report number?” A real lab report can be checked.
• “Does the description say untreated, impregnated, or dyed?” If it says nothing, assume nothing.
• “Can I see the stone in daylight, not just studio light?” Dye and filler both hide better under warm lamps.
• “What is the return policy if a lab disagrees?” A seller who stands behind the stone will answer this easily.

If it has been bleached, filled, or dyed, it is not Type A.

Common questions

Type B vs Type C, answered.

Keep reading

More on jade, from the stone up.

• What is Type A jadeite?
• How to tell if jade is real or fake
• Is my jade dyed?