Types of jade: jadeite, nephrite, and what imperial jade is

For most of the time humans have used jade, nobody knew there were two of them. The stones look alike, take the same polish, ring when struck, and refuse to be cut by anything softer than themselves. The Chinese trade noticed that some jade was slightly harder than other jade and priced accordingly, but the difference was treated as a matter of degree.

In 1863 the French mineralogist Alexis Damour ran a chemical analysis of each and found they were not related at all. One is a sodium aluminum silicate, a pyroxene. The other is a calcium magnesium iron silicate, an amphibole. They form under different conditions, occur in different places, and had simply been converging on the same appearance for a few hundred million years. Damour named the first jadeite and kept the older word nephrite for the second, and gemology has used his split ever since.

Two rows in that table are worth stopping on, because they are the ones that get mistranslated into shopping advice.

The first is hardness against toughness, which are different properties and point in opposite directions here. Jadeite is the harder of the two, meaning it resists being scratched. Nephrite is far the tougher, meaning it resists being broken, and the reason is structural: nephrite is a felt of interwoven tremolite and actinolite fibers, and a crack trying to cross it has to tear through thousands of fibers running every which way. Jadeite's interlocking grains give a crack an easier route. Drop both bangles on a tile floor and the green one is likelier to be the one in pieces. This is also why nephrite, not jadeite, was the stone prehistoric cultures on four continents made axes out of.

The second is the last row of dates, and it quietly rearranges the whole subject.

GIA dates the arrival of jadeite in China to the late 1700s. Not its discovery, not its first curiosity specimen: its arrival, as a material, coming north out of Burma into a culture that had been working jade for four thousand years by then.

Sit with the arithmetic for a moment. The jade discs buried at Liangzhu before writing existed were nephrite. The six ritual jades of the Zhou li, addressed to heaven and earth and the four directions, were nephrite. The rank tokens that said which nobleman outranked which were nephrite. The jade cases the Han sewed their emperors into, plaque by plaque with gold wire, were nephrite. The stone that became the Heirloom Seal of the Realm and carried the legitimacy of Chinese emperors for a thousand years was nephrite. All of it, every object on our page about what jade means in Chinese culture, is the stone that is not the expensive one.

And the bright emerald green that the word jade now summons anywhere in the world, the one that sets auction records, arrived roughly two centuries ago as an import from what is now Myanmar.

This is not a gotcha. Jadeite earned its place honestly: it does something nephrite cannot, which is glow. But it does mean that a shop assistant telling you that the green bangle connects you to five thousand years of Chinese tradition has the tradition slightly out of order. The five thousand years belong to the white one.

If you want the point above in the tradition's own words rather than in a mineralogist's, the Liji, the Book of Rites, supplies it in one sentence written more than two thousand years before anyone in China had seen a piece of Burmese jadeite.

The chapter called Yu Zao regulates court dress down to the cord you hang your jade from, and it assigns each rank its own stone. The Son of Heaven wears white jade on a dark cord. Dukes and marquises wear a darker mountain jade on a vermilion cord. Grandees wear a water-green jade on a plain cord. The heir apparent wears a fine jade on a patterned cord, and a knight at the bottom of the order wears a lesser stone that is not quite jade at all, on a russet cord.

Read the sequence from the top down and the color scheme is unmistakable. White outranks dark. Dark outranks green. Green is the third tier. Two millennia later the market has inverted the ranking completely, and the word it uses for the top of the green is imperial.

The trade name for jadeite in Chinese is feicui, written 翡翠, and it is one of the more charming accidents in the history of naming things.

Open the Shuowen Jiezi, the first Chinese dictionary, compiled around 100 CE, at the section on feathers. The entry for 翡 reads: a red-feathered bird, from Yulin. The entry for 翠, immediately after: a green-feathered bird, from Yulin. Put them together and you have the kingfisher, whose back is that impossible electric green and whose breast is chestnut red. Kingfisher feathers were a luxury inlay material in Chinese jewelry for centuries, which is how the pair of characters came to mean, loosely, that particular shocking green.

Then Burmese jadeite arrived, glowing in exactly the kingfisher's green, and took the bird's name. So the Chinese word for the stone predates Chinese knowledge of the stone by about seventeen hundred years, and Yulin, where the dictionary says the birds came from, is in Guangxi, several hundred miles from any jadeite deposit. The name traveled first and the stone caught up later.

You will meet these two terms constantly. Jadeite gets called hard jade and nephrite gets called soft jade, and both labels are nineteenth-century inventions that postdate Damour. The classical Chinese record does not sort jade this way at all: it sorts by shape, by color, by rank and by virtue, as the Yu Zao passage above does, and never once by which stone wins a scratch test.

Worse, the labels lead a buyer to the wrong conclusion. The gap in hardness is half a point on the Mohs scale, which is real but small. The gap in toughness runs the other way and is large. Anyone who hears soft jade and thinks fragile has been handed a fact that is technically accurate and practically backwards. If you are buying a bangle for a person who will wear it every day for thirty years, softness is not the property to worry about.

Diamonds have a grading system with letters and an institution behind each letter. Jade has adjectives. The vocabulary below is genuine trade language and every dealer will recognize it, but no authority issues these grades, the boundaries between them are matters of opinion, and the same stone can be described one way in Hong Kong and another way online.

GIA sets out the three properties that actually move the price, and gives them in order of impact: color first, then transparency, then texture. Their working test for transparency is a good one to carry around: hold the stone over printed text, and the best jadeite is semitransparent, meaning the text is blurred rather than hidden.

Imperial is the one to be careful with, because it is doing two jobs. As GIA uses it, it describes the finest jadeite: nearly transparent, vivid emerald green, no gray. As a shop uses it, it is frequently a compliment. There is no certificate that says imperial, no measurable threshold you cross, and no emperor in the story. Treat the word as a claim rather than a grade and ask what the actual color, transparency and texture are.

A separate problem from treatment, and a more common one. These are not fakes in the sense of being altered jade. They are other minerals, usually cheap, usually named so that the word jade appears next to a country.

The pattern is easy to remember once you have seen it: a place name attached to the word jade is almost always a warning rather than an origin. Real jade is described by which of the two minerals it is. If a label leads with a country instead, it is usually because the mineral name would end the conversation.

A stone can also be genuine jadeite and still not be what you were told, because it has been bleached, filled with resin or dyed. That is a different question with different answers, and it has its own page here.

Worth saying plainly, since a page like this can drift. We write about what jade has meant in Chinese culture, which is a subject almost nobody covers well in English and one we can take back to primary sources. We are not a gemological laboratory and we do not grade stones. For refractive indices, spectroscopy and the formal identification of a specific piece, GIA is the reference and we link to them above rather than paraphrase them.

What this page is for is the decision before that one: knowing which of the two stones you are looking at, what the vocabulary around it actually means, and which parts of the sales patter are load-bearing.