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Dear All

Acid treated fake jade with "expansion of tremolite" will make you sick.

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Tremolite is a member of the amphibole group of silicate minerals with composition: Ca2Mg5Si8O22(OH)2. Tremolite forms by metamorphism of sediments rich in dolomite and quartz. Tremolite forms a series with actinolite and ferro-actinolite. Pure magnesium tremolite is creamy white, but the color grades to dark green with increasing iron content. It has a hardness on Mohs scale of 5 to 6. Nephrite, one of the two minerals of the gemstone jade, is a green variety of tremolite.

A fibrous variety of tremolite is used as ASBESTOS. This material is toxic and inhaling the fibers can lead to asbestosis, lung cancer and mesothelioma.

Tremolite is an indicator of metamorphic grade since at high temperatures it converts to diopside. Calcite, grossular, talc, and serpentine are common associates of tremolite.

http://en.wikipedia.org/wiki/Tremolite
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Health issues

Chrysotile asbestos, like all other forms of asbestos, has produced TUMORS in animals. Mesotheliomas have been observed in people who were occupationally exposed to chrysotile, family members of the occupationally exposed, and residents who lived close to asbestos factories and mines. [18] Amosite and crocidolite are the most hazardous of the asbestos minerals because of their long persistence in the lungs of exposed people. Tremolite often contaminates chrysotile asbestos, thus creating an additional hazard.

http://en.wikipedia.org/wiki/Asbestos
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Pls be safe! don't buy those stuffs.

Anita

A while ago, I was handling a large number of nephrite and serpentine jade carving, rocks, slabs, with some of them seem to have rough edges and some with interesting smell, it had caused me concerns about how safe it would be to handle such material on a routine basis especially after I had read about the relationship between tremolite, actinolite, nephrite, serpentine and asbestos.

I had consulted Mike, a fellow jade collector, who is also a geologist, who assured me that it would be safe to handle such material.

You see, while asbestos can be a fibrous form of serpentine, actinolite or tremolite and nephrite is composed of both tremolite and actinolite, nephrite is really not asbestos despite what Ms. Mui tried to imply.

http://users.lmi.net/drewid/Lap_Techniques.html

http://users.lmi.net/drewid/DFNephrite_asbestos.html#Anchor-34673

In this article written by Mr. Richard Friesen, "
Nephrite, Asbestos, and Rock Dust- Safety Factors in Lapidary Work" he explained it much better than me:

"Nephrite and Asbestos by Richard Friesen

Nephrite is NOT asbestos. The confusion arises from the fact that nephrite has the same chemical composition as one of the forms of asbestos (Actinolite)."

If nephrite is not asbestos, then no matter what it was treated with, acid or alkaline or apple juice, it cannot result in the formation of asbestos and therefore they cannot make you sick like Ms. Mui claimed.

Mr. Friesen further explained:

"The characteristic of asbestos that causes trouble is its ability to easily break into fine fibers that are too small to be seen by the human eye. Nephrite does not have this character. Nephrite is a amphibole silicate but physically it is similar to chalcedony in that they both have a fibrous structure. Nephrite fibers have different directional hardness which results in its tendency to orange-peel. The real problem with asbestos is the quantity of fibers that are released when the material breaks up. The fibers are not tightly bound together and break up easily when they are disturbed. With nephrite or chalcedony the fibers that are released are just what you grind out."

Now that is a wonderful explanation.

Now does that mean there would be no health hazard with nephrite, correct? No, the writer further explains:

"So there is no problem with nephrite, right? No, there is a potential problem. Sanding any silicate can generate silica particles and silica, when freshly ground, is suspected to be even more toxic than asbestos. Wet grinding controls the heavier particles and is definitely recommended on material that does have a chemical toxicity- as well as being a good idea anytime."

Well, I guess if any of us jade collectors would be crazy enough to re-sand any nephrite jade carvings or try to create a piece of nephrite jade carving from scratch, then we better wear a industry-quality mask while we are doing so.

Now what will happen if some of us want to polish a piece of jade and that is what the writer says,

"Polishing also produces airborne particles, but I have not been able to find any reports on the carcinogenic effects of the oxides we use, so I guess we are safe there for a while. But even this may not be correct. I have heard that chrome oxide may be toxic, but I have not been able to find the data. "

Now if you would like to read his whole article, you can click on the above link and do so in your leisure time.

However, from this article written by a jade lapidary expert:

"Richard Friesen, a frequent contributor to Rock and Gem magazine as well as a noted lapidary, has graciously consented to my publishing here some articles he has posted from time to time in the Lapidary Digest and various online forums. The advice he gives is based largely on his own extensive personal experience."

It is very clear that:

NEPHRITE IS NOT ASBESTOS!!!!!!!

Therefore, no treatment on it should create asbestos.

Secondly, being a double majors in college with one of my majors being Chemistry, I am very doubtful with the automatic assumptions of many jade collectors that artificial weathering were created with acid in resulting so-called acid-treated jade fakes.

With my clinical laboratory experience, I had handled many different types of conc. acids such as H2SO4, HCL, HNO3 but I do not believe any of these acid can do anything to a piece of nephrite jade carving. The only acid that may be able to "eat up" nephrite will be HF, Hydrofluoric acid. However, it is extremely toxic, expensive and is very dangerous to handle (it will melt glass container and it will eat up the eye membrane of the handler if he is not careful). The only other means in creating those weathering on jade fakes with acid would be to fracture the jade surface with metal tools and then treat them with strong acid. Serpentine would be much easier to treat with acid or heat to produce white weathering.

On the other hand, alkali such as NaOH, lime will be much more caustic and therefore were very being used in the creation of artificial weathering on jade fakes. I know because when I was handling radioactive istopes we must routinely decontaminate the drainage sink with sodium hydroxide (NaOH) solution made from mixing NAOH pellets with water. This NAOH solution will eat up anything and will definitely create a white coat on it. Other strong alkali such as lime could probably be used for this purpose because it is cheap and easy to obtain.

Unfortunately, there are simply not enough academic literature in the studying of the effects of chemicals being used in creating jade fakes. Many methods that were described in ancient Chinese jade books were simply the results of imaginations of the book writer, such as using dog blood to soak jade to create red color, etc.

One thing is clear though, we must separate all these misinformation from actual facts when we are studying or collecting jades, or we will inadvertently pass such misinformation to other jade collectors.

Bill

Dear Bill

You said "nephrite is really not asbestos despite what Ms. Mui tried to imply."

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But nephrite is composed of both tremolite and actinolite. What "expansion of tremolite crystal" that fake jade dealer make means to you, not including whitening dust? is it safe?

Tremoite contains asbestos!

In case jade altered naturally in tomb without any forgery means, would it be safer than those chemical treatment that pushed tremolite came out of nephrite or serpentine..is it hazardous?

And the authentic one don't look horrible like those fake.

Hope this help.

Have fun
Anita

Dear Ms. Mui:

You really need to spend more time in studying and learning more about mineral
and rocks especially the difference between tremolite/actinolite and nephrite.
Yes, nephrite does contain both tremolite and actinolite, especially the beautiful Hetian jade is supposedly containing at least 95% of tremolite for it to be called Hetian nephrite jade. However, just because nephrite
contains tremolite and actinolite does not mean nephrite is tremolite or nephrite is actinolite. Just like table "salt" which is Sodium Chloride
(NaCl), contains both sodium (Na) and Chloride (Cl), but do you call salt either Sodium or call it Chloride? Since you will see Mike again when he comes back from Canada, I suggest you should really talk to him so that you would
not have such misconception that nephrite is tremolite and therefore it would be dangerous to jade collectors because tremolite contains asbestos. It is not good to try to scare all jade collectors unnecessarily no matter how good you intention may be.

Nephrite does not contain asbestos, therefore it does not matter what you treat it with, it will not create asbestos. It seems you continue to refuse to understand such a simple fact and insist in your misconception about
nephrite jade and in continuing to preach that acid-treated jade fakes do contain asbestos and therefore would be dangerous to jade collector's health. In that regard, you are very similar to the famous Dr. VM who refuses to believe that there are nephrite jade in Taiwan or in New Zealand. Incidentally, both of you believe that archaic Chinese jades could not be made of hetian jade despite recent discoveries of hetian jade carvings being found and excavated from the Lady Fu Hao's tomb (Shang dynasty). I suggest you should really watch those Chinese T.V. links provided by KK in another thread. I found them extremely educating and they explain how Hetian jade being ended up in ancient China even though they originated from the far-away XinJiang. To be a TRUE jade authority, you must continue to learn and have the courage in admitting you could be wrong.

Cheer!! Have fun!!!

B

Dear Bill

That's what you assumed.

You have to understand more geology.

Shang Dynasty is a lower Yellow River valley civilization, and where is the Yellow River originate from?.."Qinghai Province", close to Xinjiang and share the same Kunlun mountain range.

A great mountain chains in Asia, extending more than 3,000 km. From the Pamirs of Tajikistan, it runs east along the border between Xinjiang and Tibet autonomous regions to the Sino-Tibetan ranges in Qinghai province."

"Yellow river originates from Qinling mountain range in Qinghai Province, a continuation of the Kunlun Mountains."
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Is it possible that Fuhou picked up jade from Yellow river base which are from Kunlun mountain and share the mineral content as of those in Hetain?

And Xinjiang share kunlun mountain range with Gansu province...and Gansu province is next to Inner Mongolia... will their jade have the same mineral content as the same as Hetian because they share the same mountain range?

Think about it!

Have fun
Anita

Dear Ms. Mui:

I believe what you are trying to say is the understanding of "geography" and not "geology",correct?

I believe you should watch these fantastic Chinese TV video links listed my kk in his message:

http://www.asianart.com/phpforum/index.php?method=detailAll&Id=40798

It would surely answer a lot of how Hetian jade being imported from XinJiang to mainland China during ancient China for you. Please understand that I had nothing to do with their contents and it is also possible that their explanations for the transport of hetian jade may not be correct. However, lacking better contradictory evidence, I believe their explanations are more credible than yours. Incidentally, in one of the videos, is one of your jade idol, Mr. Gu Fang himself.

Enjoy and have fun!!!

B

The diagram speaks for itself.

By the way it would be geography, not geology.

B

Bill

Off course the main mineral content would be the same, but it doesn't mean that they are truly really from Xinjiang, Hetain.

"They said probably imported from Khotan,, not it surely is!"

Again...stone from the same mountain range will contain the same mineral content...Like brothers and sisters they share DNA but it doesn't mean that their face and body look the same.

Fuhou was a female warrior, she would be paid tribute by the surrendered tribes and minorities, and Fuhou was an antique jade collector. Longshan jade was found in her tomb which doesn't mean that all "Shang Dynasty jade" in her tomb were all made with really, truly Khotan jade. It would take life to travel to Xinjiang to pass through Gobi Desert, thick forest, wild animals, decease, bandits...etc..just to give raw jade to Fuhou.

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The topic is about danger of tremolite dust...why now is Khotan jade, Fuhou tomb and Gufang?

I am tried.

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Once tremolite in nephrite is artificially push out, it is hazardous to your health.

Artificial food coloring, and the natural one...which one is the safest?

Think about it.
Anita

Quote from the Introduction by Yang Jianfang (Yeung Kin-fong), "Jade Carving in Chinese Archaeology - Volume One":

"As to the mineralogical qualities of jades in the late Shang period, 61 specimens from Anyang were studied by Dr. Li Ji in 1945. The result, being limited to type, colour, specific gravity and hardness, is imperfect for lack of the most important factor, the examination of raw materials (ZYLYYJ, no. 13, pp. 179-182). However, a few jades from Yinxu were said to be made from Nanyang yu. In recent years, a number of jades from Tomb of Lady Hao have undergone scientific identification providing different results. In an examination report, seven of the eight specimens are tremolite, a type of nephrite (KG, 1982, no. 2, pp. 204-206). In a primary excavation report, among more than forty pieces of Lady Hao jades, most are similar to Xiuyan yu, some to Nanyang yu and a few to Hetian yu (KX, 1977, no. 2, p. 74). But in the formal excavation report, among some 300 pieces of Lady Hao jades, most belong to nephrite somewhat like those from Hetian, Xinjiang, only three specimens resemble Xiuyan yu, and a few are Nanyang yu, marble or silicious slate ((42) p. 114). The latter identification, if reliable, would be another surprise to students of Chinese archaeology and art. How jades were transported from Xinjiang to Henan over 3000 years ago remains a mystery, although records such as "obtaining jades" and "levying jades" are found in oracle inscriptions of the Shang Dynasty, and a jade halberd from Tomb of Lady Hao bears an inscription which says that the piece was a tribute offered to the king of the Shang Dynasty from Lu, a country acknowledging allegiance to the Shang Kingdom."

"The geological sources of nephrite used by early cultures in China are not currently known. Such sources may have been depleted in antiquity, as nephrite can occur in small localized deposits. Research involving scientific methods on early Chinese jades has been addressing issues related to the geological origin of nephrite in early China, as well as jade production and use (Douglas, 2003). Analysis of early Chinese jades at the Freer and Sackler galleries using X-ray fluorescence spectroscopy (XRF) indicates that the geological sources of the material used for these jades are most likely associated with dolomitic marbles. The 145 jades analyzed by XRF were found to be consistently low in Cr2O3 (< 0.08 percent by wt.) and NiO (< 0.01 percent by wt.), characteristic of nephrites associated with dolomitic marbles. Future work on geological sourcing of nephrite should concentrate on these types of deposits in China.

Of particular interest are the FeO and MnO contents, which have been determined by XRF to point to simple source patterns for the nephrite used by the Neolithic cultures of Hongshan, Liangzhu, and Longshan, possibly involving one or more related geologic sources for each culture. Longshan jades were found to have unusually high FeO (0.35-17.95 percent by wt.) and MnO (0.02-0.89 percent by wt.) contents, suggesting a source particularly rich in iron and manganese. Jades of the Shang and Western Zhou dynasties show a wide range of compositions, suggesting multiple nephrite sources for these objects. XRF is a simple noninvasive tool for determining minor elemental oxide concentrations, but further work on jade sources will need to involve an expanded suite of analytical methods on a wider range of jade objects and geological samples from China."

Janet G. Douglas
Department of Conservation and Scientific Research
Freer Gallery of Art/Arthur M. Sackler Gallery
Washington, D.C.

Have fun
Anita



URL Title :A Review of Some Recent Research on Early Chinese Jades

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