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how do you grade jade?
i have looked on the internet at jade necklaces
have seen prices from 25 dollars to 2500 hundred
what am i looking for?

That is a good question: "how do you grade jade?"

But a better question may be:
"What exactly is jade?"

It is almost like asking "how do you grade gem stones"? You have to identify which gem stone: diamond, ruby, emerald, etc. first

Same applies to jade, how do you define jade?
Do you use only the narrower western definition of jade: jadeite or nephrite?

Or do you expand it to the broader definition of jade used by the Chinese:

Any stone that is beautiful, in that case it will include jadeite, nephrite, xiu yu (serpentine or bowenite), jasper, agate, crystal, Dushan jade (feldspar), turquoise, etc.

If you want to apply the five virtues of a gentleman on the definition of jade, then there is only one jade material that contains all five virtues and it is the Hetain nephrite jade from Xianjiang.

The problem is that is no known and agreed upon grading standard used in grading Hetian jade, most used color and I said something about it in other message and not to repeat myself here.

If you are only interested in grading jade necklace made of mostly jadeite beads, then you may use A, B or C color and you can google the common grading standards for jadeite. Unfortunately so many artificial agents can be applied to inferior jadeite to make it appear to be top grade. Unless you are a real expert, I would stay far away from buying any jewelries made of jadeite because many are fakes even the very expensive ones.

During the last recession in USA (2008-2009) I did buy some pretty nice 14 gold jadeite jewelries for my wife (ring, pendants) but I only paid for what gold of the item was worth and therefore got the jade free.

A few years ago I was at a Chinese mall in Toronto and this Chinese business lady whose shop we shopped show me a jade pendant she just paid $5000 Canadian dollars (at that time Canadian dollar was higher than US dollar, believe or not)from a jade vendor in the same mall. I told her I collected jade and she show me the piece. I asked her if she knew if it was real jade or good jade, she said no but she trusted the guy. I did not want to say any more.

These days, buying any jade carvings or jadeite jewelries can be a very risky business.

I surely hope others will share their experience in "grading" jade with us. Thanks in advance.

Super

I thought xiu yu or xiuyan yu (yu = jade) mined in the liaoning province inside China mainly consist of neprite. This guy sure must have got it all wrong then.



URL Title :Study on Xiuyan Nephrite

There were rumors that nephrite were once being mined at different parts of China, including Xiu Yang, Liaoning. As a matter of fact, once several Chinese professors collected different rock samples from different areas of where Hongshan tribes were known to reside and found some of them were nephrite. The famous Hongshan jade expert in China, Mr. Chou Nam Chuen, once discussed the credible material in the making of Hongshan jade carvings and he believed that some of the jade material at Liaoning that were used to make HS jades were nephrite and he called them "old xiu yu". I also came across articles that mentioned nephrite were still found in Xiu Yang but they were "sugar color" and their quality are not good enough in making high-priced carvings. However, I can neither confirm or reject such story. Lee once said in this forum that there were indeed nephrite from Liaoning. It is also true that some of the genuine Hongshan jade carvings were indeed made of nephrite with quality matching that of Hetian, Xinjiang. Unfortunately, nobody can confirm their original source. There is a slight possibility that once there very small nephrite mines at Liaoning but they were soon exhausted to the point that nobody can identify and confirm their sources. A good example will be nephrite jade that were once mined at Huiliang, Taiwan during late 60s and earlier 70s. The nephrite when first found were too brittle for making carvings until a new process was discovered to "carve" them. Miners worked 24 hours a day to mine those nephrite and soon all the nephrite mines in Taiwan were exhausted. Now barely anybody knows that nephrite was once mined in Taiwan. Also I have yet been able to see and confirm any jade carvings that were made of Taiwan nephrite jade some of which may look like jadeite, some like nephrite (plastic look) and some like Dushan jade. Same may be true with nephrite jade once mined in Wyoming, USA. They were now all gone.
Same may happen with Hetian nephrite jade soon, with so many people went and hunted for Hetian jade, it will soon exhaust, just like any natural resource in earth, this is sad but true. Once you can buy average quality jadeite pretty cheap, now it has become much more expensive to find any at decent prices.

If you read carefully the abstract of your article in which it says:
"They have similar refractive index of 1.60-1.62 and density of 2.660-3.020 g x cm(-3), and only the density has some differences with different colors."

I found the densities of their "nephrite" samples - 2.660-3.02 extremely interesting because if you have ever studied nephrite, you would know that the minimum density (or specific gravity) to call a stone NEPHRITE will be 2.90. I believe some nephrite that may have some impurities may have densities as low as 2.82-2.88, but anything lower than 2.80 I would not call it nephrite. The author included this " He-Mo nephrite, a special nephrite from Xiuyan' to me is peculiar because I had encountered this Hemo jade before, they kind of resembling nephrite, could not be scratched but their densities were too low to be nephrite, they were used to make Hongshan fakes. I had studied and analyzed some of these Hemo jade and can tell you with conviction that they are not nephrite jades. I had also come across some of these interesting material that I believe contains both serpentine and nephrite, cannot be scratched but with a much lower density - 2.80-2.86, that were used to make Hongshan fakes. There were also some unique material that were used to make Liangzhu fakes (small congs, fishes, Huangs with taoties), upon tested they were actually nephrite, some I believe were imported into China but others according to Friends of Jade, were from Liaoning. I cannot confirm or reject this either. If I have time I may post pictures of a few here.

In short, there is a good possibility that nephrite jade may be indeed once found in Xiuyan Liaoning, possibly being mined there or imported there (note: Lapis were never found inside China but was transported into China as early 600 BC, that shows you anything is possible). However, today when one refers to Xiu Yu or Xiu Yan jade, they are being referred to serpentine jade (can be scratched) or so called Bowenite (not really a good term, IMHO) which cannot be scratched. There is another really interesting material, dark green like nephrite, cannot be scratched but the density is too low to be nephrite. I have yet been able to obtain and study a real bowenite rock sample. I believe it has become a general term for every serpentine sample that cannot be scratched. More studies may be needed.

Ok, thank you for your answer. I read somewhere that nephrite from lioning have a much higher content of actinolite than nephrite from xinjiang which mostly consist of tremolte, meaning they are chemically different.

Also the different chemical composition, actinolite vs tremolite, could explain the abnorm density.

Have you noted that some of the xiu jade on ebay looks very similar to the material of some jades sold at Christie's?



URL Title :Xiu Jade - eBay

A charming jade frog that sold for no less than $30.000. I find it extremely interesting if this jade material is actually xiu jade, even more if it's hard serpentine. From the photographs they look very much the same.

URL Title :Xiu Jade(?) - Christie\'s

Links are not working.

The xiu jade on ebay is item number 190974185745.

The jade from Christie's is LOT 1116 - SALE 2297
26 March 2010.

I can no longer find the eBay piece, may be you can post a copy of its picture here.

I did find the Christie's piece and it described its material as jade/jadeite and that of Qing dynasty. I could not enlarge its only one picture, therefore hard to tell its exact material. If it is Qing, it could indeed be made of jadeite. It could also be made of white/black Hetian nephrite jade. Does not look like Xi Yu to me at all. Why do you think it was made of xi yu?

I just thought the materials look similar. Both have a very glossy appearance and a part of the Christie's piece looks more translucent than nephrite usually is.

There are plenty of such black and white xiu jade items available from ebay but usually the quality of those carving are not good.

Interesting, if only based on the two pictures posted here by you, they did look similar, just like you said. But compare the luster of the two, may be you can see the difference. The luster on the Christie's piece is much better and more natural, it can be either jadeite or nephrite jade. I have no idea what the material of the eBay piece is and I wonder if it is really black and white, or perhaps dark greenish/white. It does not look like the usual Xiu yu I had encountered. I wonder if it can be cheaper jadeite, agate or some other soft stones. It is hard to tell for sure unless I can study one in person. I do not believe it is nephrite though. There is a total lack of luster on it, that may rule out jadeite because you will see some luster on even modern jadeite.
May be you should acquire a piece at reasonable price to study. Best luck.

P.S.
Unlike some collectors' beliefs, luster on a jade piece has nothing to do with how hard the stone is or how much you wax it. The luster of Qing jade pieces, especially those that in or before the QianLong era was so great, like satin, is because it would usually take a year or longer just on the polishing part of the piece. It was not until polishing with high hardness grit (like corundum and diamond) was invented in the late Qing dynasty that they were able to greatly reduce the time of the polishing. If you ever compare the luster (polishing) on a genuine Qing dynasty piece with that on a modern jadeite piece, you would understand what I tried to say.

I allready have one inexpensive black and white xiu jade carving bought from ebay, but unfortunately I don't have the equipment to make density test. But I can tell that it's not greenish black, but black black.

I also have some other low value xiu jade carvings bought on ebay in a material that looks very similar to the material of the warring states bracelet that sold at Christie's for more than a quarter millon dollars, and I've been thinking if that one is actually also xiu jade.
This material has a sort of golden color and appear very translucent. It can be scatched with a knife.



URL Title :Warring States Jade Bracelet

Then I have a small selection of identical cicadas but in different kinds of jade materials. One of them is a colorless material that is also very translucent, and by it's visual appearence it could be mistaken for 'icy' jadeite jade, but after looking at xiu jade items om the internet, I suspect the material of this one also to be xiuyan yu.

The cicada itself could be arcahic, but I still need to find a valid reference for the style.

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