Type A, B and C jade: what the letters mean

A type A jade bracelet is one made of natural jadeite that has not been bleached, filled or dyed, and has been finished only with wax. That is all the label says. It does not guarantee quality, because untreated jadeite runs from coarse, opaque stone worth very little to the finest gems. And it does not guarantee itself: on a tag or a listing, “type A” is the seller’s claim about treatment, and it is only as good as the independent laboratory report behind it.

The letters describe what has been done to a piece of jadeite, not how good it is. This page uses them as GIA and gemological laboratories do.

Type A, B, C and B+C at a glance

Type	What was done	Effect on the look	How it holds up	Effect on value	How it is detected
A	Nothing beyond the traditional wax polish	None. The stone looks the way it formed	The standard the others are measured against	Full value for its quality, which may be high or low	A laboratory report finding no impregnation and no dye
B	Bleached with acid, then impregnated with polymer resin or wax	Brown and gray staining removed. Cleaner, brighter, more transparent	More brittle. The filler can discolor	Roughly 5% to 10% of the equivalent type A, by one trade estimate	Etched web on the surface, sometimes a UV glow. Conclusive only by infrared spectroscopy
C	Dyed	Green, lavender or orange-brown color added to pale stone	Dye can fade with time, heat or light	About $2 to $20, by the same estimate	Color lying in a net of cracks and grain boundaries. Spectroscope
B+C	Bleached, impregnated and dyed	Both of the above	Both of the above	As for B and C	Both of the above

Dealers describe B+C as the most common kind of treated jadeite in the low-priced market.

Where the letters come from, and what they leave out

The system comes from the Chinese and Hong Kong trade. Dealers there describe the letters as commercial shorthand for what the national standards call enhancement and treatment.

Three limits follow from that:

• A is not a quality grade. Dealers point out that a coarse-grained A bangle is worth very little even though nothing has been done to it.
• The letters are for jadeite. Nephrite can also be dyed, waxed, acid-washed or given an artificial colored skin, according to Chinese dealers, but those treatments are not normally labeled A, B or C.
• Dealers use the letters loosely. You will meet “D jade” as slang for an imitation that is not jade at all, and sellers who describe B jade as resin-filled only. The laboratory definitions in the table are the ones to hold a seller to.

Wax, and where the line is drawn

Wax does not make jade treated. Waxing is part of the traditional finishing of virtually all cut jadeite. As the Gems & Gemology study of the Burmese jade trade describes it, the polished piece is boiled to open the pores, soaked in melted wax and buffed, which improves luster and fills surface pits. Serious buyers expect it and it does not reduce value.

The line is drawn at bleaching. Jadeite that has been bleached with acid and then heavily impregnated with wax instead of resin is also B jade. GIA documented such a bangle and noted that many traders wrongly describe B jade as resin-only, which leads buyers to assume wax-impregnated jade is type A.

How B jade is made, and why

1. Coarse, loosely textured, stained low-grade jadeite is selected and rough-cut into slabs or bangle blanks.
2. The blanks are soaked in strong acid, sometimes heated, for as long as several weeks.
3. They are neutralized with an alkaline solution, washed and dried.
4. Resin is forced into the emptied spaces.
5. Only then is the piece shaped and polished.

What the acid removes is the brown or gray part of the color, probably iron compounds sitting in fractures and along grain boundaries, according to the GIA study of bleached and polymer-impregnated jadeite. The stone left behind is white to green, cleaner and more porous. Filling it with clear polymer makes it brighter and more transparent, so cheap material looks like a much better grade.

B jade is recent compared with dyeing, which is much older. A specialist US dealer dates its appearance in East Asian markets to the early 1980s, and a Chinese gemology instructor places it in the late 1970s to early 1980s, first in Hong Kong, where it shook buyers’ confidence because at first there was no good way to detect it.

What is dyed jade (type C)?

Dyed jade is pale jadeite colored green, lavender or orange-brown with organic dyes. The color is not stable. The authors of the Gems & Gemology study report seeing dyed green and dyed lavender jadeite fade, the green more readily. Dyes can also fade with heat or light.

Dye is recognized by where the color sits: concentrated in veins, surface cracks and along grain boundaries in a net-like pattern, where natural color is smoother and lies within the grains. Two instruments go further, though few buyers own either:

• Spectroscope. A broad absorption band at about 630 to 670 nm is considered proof of dye in green jadeite. Natural chromium-green jadeite shows sharp lines at about 630, 655 and 690 nm instead.
• Chelsea color filter. Gem-A’s instructions for the filter list green jadeite as appearing dull green and say only that certain dyed green specimens may show a red or pink tint. A red or pink tint is therefore a warning, and a stone that stays green has not been cleared.

A piece can also be partly dyed. GIA examined a carving in which one green band was natural and other green spots were dyed, and warned that testing only one part could miss the dye. A Chinese dealer describes the same thing with bleaching: bangles in which a single stained area was masked off and bleached, so that most of the bangle looks and tests natural. The whole piece has to be examined.

Treatments and tricks outside the letters

• Heating. Red, orange and yellow-brown jadeite owes its color to natural iron-oxide staining, and the color is sometimes intensified by heating. Chinese dealers say heated material is still certified as jadeite, because nothing foreign is added, and that most testing laboratories there cannot or do not separate heated from naturally red stone. The color itself is covered in red jade.
• Colored polishing compound. A newer trick, mostly on coarse-grained bangles: green, lavender or blue compound used in the final polish. The color lies only on the surface, lodges in pits and cracks, and wears off. A tissue moistened with alcohol picks it up.
• Coatings. The Gems & Gemology study documents pale cabochons coated on top with green plastic, given away under magnification by peeling at the edge, and a dye layer under varnish.
• Closed-back settings. The same study describes very dark green stones hollowed to a thin shell, filled with resin and set with a closed back so that they look like fine translucent green. Chinese dealers describe pale jadeite mounted over colored film, foil or lacquer. Be cautious with any strongly colored stone whose setting is sealed at the back.
• Glued repairs. Broken bangles are sometimes glued back together. The glue often fluoresces blue under UV.

How treated jade ages, and how to care for it

B jade does not last like untreated jade. The acid leaves the stone more brittle and the polymer can discolor with time. A specialist US dealer says it often discolors, can fracture with minimal impact, and that household detergents and acetone can break down the polymer. The gemologist who writes for Geology.com says type B can deteriorate within a few years.

That sets the care for a treated piece: keep it away from detergents and solvents, protect it from knocks, and keep dyed jade out of heat and strong light. General cleaning is covered in how to clean jade.

What treatment does to price

The only published figures found in English come from one US jade wholesaler, so read them as a trade estimate and not a laboratory finding: B jade at roughly 5% to 10% of the value of the equivalent A jade, and dyed and imitation pieces at between $2 and $20.

Durability is only part of the reason. The treatment is applied to poor, stained material that was worth very little to begin with, so a good-looking B piece is a cheap stone made to look like a better one. What does make untreated jadeite costly is explained in why jade is so expensive.

How a type A jade bracelet is confirmed in a laboratory

Treatment is detected reliably only in a laboratory. The GIA study found infrared spectroscopy to be the one method that gave conclusive evidence of polymer impregnation in all cases, and it also separates wax from resin. Refractive index and specific gravity do not help: the bleached, wax-impregnated bangle GIA tested still measured 1.66 and 3.34, the normal values for jadeite.

A report that supports a type A claim states both the species and the absence of treatment. A certificate that says only “jadeite” is worthless for this purpose. A GIA report quoted in a Sotheby’s catalogue shows the kind of wording to look for: the jadeite jade “has no indications of impregnation”.

Selling B or C jade is legitimate when it is disclosed. In the United States the FTC’s Jewelry Guides call for disclosure of gemstone treatments that are not permanent, that create special care requirements or that significantly affect value. A specialist US dealer notes that many sellers nonetheless do not disclose.

The hands-on routine for a bangle is in how to check a real jade bracelet, the light and UV technique in checking jade with a flashlight or UV light, and every home test with its limits in how to tell if jade is real.