Dear Xin,

Thanks for your information Contact with Mr. Ezkenazi. I think i Will have to Contact with someone of Oxford too.

Thanks for your advice Nicdan.

Dear Nic,

you are very right. A vase like this one will not be accepted by the major auction houses (Bonhams, Christie’s or Sothebys etc.) even if it will have a positive TL test result by Oxford Authentication, because of the evident discrepancy with the genuine ones.

The reason being that the potential purchasers, due to the high value, are only high end dealers like Eskenazy, Marchant, etc here in Europe or others in China, who buy for themselves in prevision of future sale or on behalf of wealthy collectors/investors.

Those wealthy collectors usually do not buy directly, they buy through high end dealers.

And those high end dealers/experts do not buy if not convinced by the piece itself, regardless if it has or not a TL test.

Giovanni

Dear Giovani,

Yes, I need facts how they make a fake with the nearly exact same mineral compostion.   ?

1. 

It seems to me it is may be possible gto make it but you need a lot of investigation in technics, time and knowledges .

(Dorin Stoneham is right to say not to give out  to much details!  But we get more then this ICP/MS ++ in

background  "forensic -methods ")

If we talking about pottery we have to be a little bit a "potter" to understand ther base of art-work !!!

And at the  end you may be get the similar porcelain material to make a vase and now what and how they make a Vase ?

from it with orignal painting elements ?  Ok and at least  they have to fired it !  Yes or no ?

Did you read the report from my partner Raymond Bove ?     

By the way  here another sientific report from another partner lab from me  

That is the end of all study anywhere  like Jingdezheng  because if you try to cheat this ánalyses of making  original fake

it will be endless and can not be payed .

2. To your question about  why (Major  ) Auction  houses more handling of sure provenance and I am not

able to give you an answer because I do not test provenance .

If you like I can mail you a private statement from my  clients experineces why they do it !

My partner and cooperation Lab   Recenart Finnland

www.recenart.com. can you give details how they find out faked or real provenance by testing  objects

like ceramic , important old /modern art paintings  +++. sold from major experts-dealers -gallery -collectors

and auction houses )

Best regards

ralf

Here is the b&w copy, again sold by an Auction house on Liveauctioneers, again in the same price range, 3,850 US$. This was sold in 2016.

https://www.liveauctioneers.com/item/43887859_a-ming-dynasty-blue-and-white-moonflask-yongle

Giovanni

I think Labkotalla makes an interesting point regarding the dating of artwork. I believe that with oil paintings the testing of the paint is merely the baseline. It is in no way conclusive evidence? 

There also needs to be provenance AND acceptance by a panel of experts. 

Nic

Dear Nic Dan ,

right Sir .

Have a look to that about rules !?

http://authenticationinart.org/universal-rules-authentication-process/

I think this will be at all th right way

regards

ralf Kotalla

Dear Ralf,

If I understand you correctly, it seems that you do not think possible that today they can make the exact porcelain body and glazes once they know and have the same components.

I repeat, I am not a potter, but I am sure that it is perfectly possible. Please read “Chinese glazes” by Nigel Woods.

You are asking how do they made the vase? Very simple, in the same way that they did four hundred years ago! Where is the problem?

And how they fire it? By knowing exactly the original firing conditions, atmosphere concentrations and so on, with the only difference that today they can control everything in much better way, so they do not have the production waste that they had at the time.

I strongly suggest you in not thinking that to make something special it is necessary to do a lot of search and works, and hence it is not possible to make it at low price. Do not think with Western parameters in this field. I too was thinking the same but had to accept the evidence that in China they can do it at very low cost.

The studies that you have provided are not demonstrating that the object under test was original. They are only shown that the same ingredients are there, that’s it. It is not enough. Thermoluminescence is much better than that, because it gives an indication of time; nevertheless in a minority of cases it can fail and I think that you know that.

All what your partner in Finnland can do is to certificate that the composition of the object under test is the same of known genuine ones, but he can’t date it. Of course he can certificate that an object is not similar to the genuine ones, hence probably fake.

Just a note about what they found in the test of the Tang statue. They found a strange composition of the body on the neck, at the back of the head. It should be because (they probably do not know this) that on almost all those Tang statues the head is made separately by the body. The statues was made in a sort of industrial scale, with different types of bodies and different heads. By coupling for example two different heads on two bodies of the same type they obtain two different statues.

If you look at many Tang minqi statues you will clearly note the joining band at the neck. It is just where they find the different composition.

Giovanni

Hi Ralf, yes, that confirms my understanding, that authentication is a multidisciplinary task, so the findings of testing alone would be insufficient to prove authenticity. The process includes robust questioning of the materials (porcelain in this case) the techniques (how it is painted) and history (provenance).

So even if it is accepted that the materials are contemporaneous and that the results could not be reproduced by fakers, the technique and history would still need to proven?

Nic

Yes Sir , right  !!  

Not allone and not without !    See again Authentication in. Art !

TL-testing give the dates-period of last firing , 14 C analyses the point of death ex. by bone , ivory , cutting date of wood...

Both are so called absolute methods !! 

best regards

Ralf Kotalla

With all due respect, if it was absolutely, 100%, a guaranteed method of authentification, the other components would not be required, but they are, because it is universally recognised that the results can either be misleading or that the fakers have found/could find a way of falsifying the results. 

Nic

Dear Giovanni,

..............

   Right !  Good fake has to be made in the same way like in the past , same technic of firing +all special details to each culture technics !

    Easy to find out with firing with electro-oven, not handmade ...

If the use glue instead of firing , we get several information by drilling , preparing -cleaning - and testing process that 

it is not fired !!

It is not the price in China or anywhere  ???? !! 

I do not thinking  ,

I (we ) get experience 40 years with all different ways to cheat others incl. physical effects!   

Sorry Giovanni please note that every report can only speak about what he had done 

It is absolut physical system and idenpendent !!  Please note my working condition attached in my reports 

Bestr regards

Ralf

I agree with

http://authenticationinart.org/universal-rules-authentication-process/

Dear Ralf,

sorry but we are thinking different. To me you are saying nothing conclusive, to you I am not understanding you.

I remain on all the points that I have said in my previous message, but you are seeing them differently, I do not know what to do.

Today’s condition to reproduce an ancient pot, under the point of view of potting and firing, are much better and less expensive than before. Ask a potter.

You evidently think that today’s potters are not making pots by hand. Just go to Youtube, a lot of potters still works with the same technology.

Of course I agree that a modern pot will be detected by the TL test, I said that already. But there are exception and is not mine who will understand or explain why. You are in better position to understand that, if you wish.

About values in China, anybody that had direct experience can confirm what I said.

According to you, those reports examining glaze/body composition are giving a conclusive answer about dating. That is your idea, but sure is far from being true. They can just provide the list of the ingredients, which to me is not enough. And, be sure, not only to me: ask Marchant if he would buy an item only because of those reports, we will laugh, sorry to be frank.

I never expressed doubts about your working conditions or your professionality.

I think that I have not been clear or you misunderstood what I said about the detached heads of Tang figures. I didn’t mean that it was a repair or a restoration. I was suggesting to your partner that what he found strange is not strange indeed, it is normal on Tang figurines. It was made at the time, it is not a restoration. In case he didn’t know.

I too agree with that “Authentication in art” document. But it is saying the same that I say, you are reading it only under your perspective. It fixes rules about how to approach the matter, it is not saying that scientific analysis alone is enough for dating a piece.

It is useless to continue debating if we think different. I am not doubting the validity of TL test, I repeated that it is the only real dating process, but it is not absolutely always reliable, at present knowledge.

And by the way here we are discussing a vase that is evidently not Ming to any expert, regardless any test.

Giovanni

There is some info here about the problems of TL dating and how it can be faked.

https://www.chinese-antique-porcelain.com/thermoluminescence-dating.html

Please think about and read it

Drawbacks:

• Exposure to an accidental fire may not necessarily damage ceramics, but their energy level can be reset.
•  
•  Right  250-350° reset to cero . Standard last firing-age- TL calculation  use an plateau between 280-380 °
•  
• A thermoluminescence test also resets the stored radiation energy, which afterwards accordingly has a thermoluminescence age equalling zero.
•   Pre-heating a sample will be used for setting a socalled cero-line 
•  
• Any other exposure to the minimum amount of heat will reset the accumulated radiation energy
• Other forms of energy may also cause a release of the stored radiation energy. Additional causes for resetting the energy level are: grinding, crystallization, exposure to sunlight or heat.
•  
• grinding   never  by using right tools and handling with it well
• , crystallization -   rare  not seen on Tang Ming Yuan  Quin !? sometimes possible ,
• exposure to sunlight     only surface 1 micro millimeter , will be removed by sampling  ,OSL - Yes 
• or heat  Right  250-350° reset to cero . Standard last firing-age- calculation TL .
•  
• When an item passes through X-ray safety inspection at an airport, or customs inspection at a sea port, the stored energy can be reset or reduced, resulting in an unreliable age test result.

         the stored energy can be reset ???   Total wrong ,not understanding the TL-basics !

Defeating this dating test:

Exposing ceramics artificially to radiation will enable fakers to artificially produce a high level of stored radiation energy.

 Gamma parts !   not Alpha and beta !!!

Currently, it seems that some use X-rays for this, but the "loading" with this sort of high energy can result in a TL age that is much higher than an item could possibly have, if genuine.

     It seems!?            Facts  , example test puplications ? 

For example, a "Tang" dynasty item may show an age of 2000 years. This would expose the fact that it was artificially irradiated.
However, as soon as a way is found to accurately "add" the proper radiation dose, the thermoluminescence dating method is not reliable anymore.

 Example tests please , you see 2000 years only by Han culture samples.

However, it appears that thermoluminescence dating is feasible only for porcelain of an age that is in the hundreds, or thousands of years. With Chinese ceramics this would mean that only ceramics older than the Qing dynasty can be measured properly. Interpolation is used to compensate for this. However, this again means that short-term measuring is simply not completely reliable.

It is a meaning! nothing more 

There a lot of TL-reports around incl. Oxford tests from Qing period. More then helpful to use additional ICP-MS. AAS ++ analysis to the Tl-test.

Hi everyone, I think this is the most interesting part of the article of Ralf Kotalla. About Tl test of porcelain and the dangerous of being irradiated

"There have been rumour circulating lately about recently fired Chinese pottery being
artificially irradiated to circumvent TL dating. While this is certainly something
we watch for, there is little real cause for concern. There are several reasons
why this dose tampering is difficult to impossible to achieve successfully. First, it
is difficult to get the dose right without considerable research into the properties of
the clay and access to expertise in TL measurements. Second, it is very difficult to
get that dose sufficiently uniform over the extent of the entire object. It also and
obviously requires a sophisticated means of irradiation, not easily available here,
let alone in China. There are many considerations that we will not detail so as not
to offer 'aid and comfort to the enemy'. The 'impossible' part is that different size
grains in the clay actually have different doses in a naturally irradiated ceramic,
but will have the same dose in the artificially irradiated example. This fortunate
phenomenon is due to the heterogeneity of pottery clays, which are a mixture of
fine grains (silt) and coarser grains (sandy inclusions). The radiation dose we measure
in the lab is due to a mix of different kinds of radiation: alpha particles (which
are heavy and have a very short range in matter--typically about 25 micrometers or
1 thousandth of an inch), beta particles (which are light and travel up to several
millimetre or 1/16 to 1/8 inch), and gamma rays (which can pass through up to 30
cm or one foot of mineral material). The major part of the natural radiation dose is
due to alpha particles, and the alpha emitting nuclides-- uranium and thorium and
their daughters--are primarily found in the fine grains. Because of this, the fine
grains have the maximum dose, while the larger sandy grains have that dose only
on their surface, and a considerably smaller dose in their interior. If the different
size grains are measured, and the dose is found to be the same, there is good evidence
of dose tampering, and the converse is true as well. When all these considerations
are taken together, it is extremely difficult to get an artificially dosed object
past routine TL dating. Given the quantity of older pottery available in China,
your concerns should be directed more toward pastiches and assembly of new objects
out of old fragments. There is one problem area, however, and that is porcelain.
This material is so high fired that it actually becomes a glass with small islands
of quartz usually remaining (which makes TL dating of porcelains possible).
In theory, there should be a difference in measured dose between small and large
quartz grains, but the glass matrix makes it extremely difficult to extract the grains
intact"

Not only Kotalla say this, Oxford Lab afirm too that they can detect with a TL Test  if a piece have been irradiated.

I believe that scientific proof should be the principle of authentication. The experts have to clasify, explain, determine the importance and value of each piece, as knowers of the cultures. They have the knowledge of  I think if the experts dont agree with a scientific test we have to repeat the test or to do other test to confirm or deny. But i believe that science is better than the best human eye.