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Dear Sirs,
I note with interest the discussion between Mirceau Veleanu and Wingchuntaiji about raised crystals.I have seen similar discussions in other forums. If possible I would like to kill this myth about raised crystals.
It is said that raised mineral crystals are caused by clay minerals or similar forming in and around large crystals in a rock matrix. The clay minerals as they form occupy a larger volume than the original mineral so exert a force to push out the larger crystal.This phenomenon does occur in nature, but the surface of the rock will have a distinct appearance. Yes, there will be raised crystals, but also there will be pits in the shape of the large crystals that have fallen out. There may also be signs of breakage on the surface as the crystal has been forced up and out it has broken the surface.
I have have never seen anything like this on jade items.
I have seen what appear to be raised crystals but with out the pock marks of the missing ejected crystals. These are relic crystals that remain after the surface has been corroded away by some agency.
What has happened here is the finer matrix being more susceptible to corrosion, has dissolved away, leaving the larger crystal behind, so relative to the surrounding fine matrix the crystal appears raised.
Now, literally the $64,000 question is what caused the relic crystal? Natural agencies such as soil acids, decomposing body fluids may cause corrosion. Unfortunately, these actions can be imitated by modern chemical treatments.
One clue to age and natural processes being responsible is that there can be a defined zoning in the article, due to the migration of ions such as Fe, which causes banding/zoning. This is very difficult to imitate.
However, this zoning may not always occur, and as usual one must look at the holistic nature of the jade piece, design, tool marks etc, before reaching the final verdict.
Mike

Dear Mike,

Basing on what you said that raised crystals are possible, but you expect to see at the same time the drop holes of the crystals after the crystals were being pushed out.....! My agrument is that what if the crystals were pushed to the point that they have not dropped out yet???

I have seen raised crystals that have not been pushed out yet. I have seen drop holes that were resulted from the crystals that fell off, and I also have seen both raised crystals and drop holes that were presented on the same jade. These surface crystals are clearly different than the eroded "islands" that remain on some jade surface!

You know that it is not a myth, and it is just a matter of acceptance from the people who base mainly on the outdated paradigms!

It would be unusual for all the crystals to be at the point of not quite dropping out, as some would be nearer the surface than others. So I would expect to see the variation from part raised to dropped out.
It also depends on enough clay to be made under the crystal to have the force to lift the crystal up.
The phenomenon does occur but I have yet to see an example of it associated with a man made jade item.
Regards

Mike

Dear Mike,

You are welcome to email me at wingchuntaiji@gmail.com so that we can make some more in-depth discussions between you and I!

We always need more than just one observation to determine the age of a jade item. We need to look at all possible indications of any jade. I have developed certain techniques to aid in determining the age of archaic and antique jades especially on Sheng Keng archaic jades. Too bad, most people would not listen! I took advantage of my techniques for many years!

Raised crystals is just one of the indications. Most artificially raised crystals can still be identified by well-trained experts.

I am a traditional jade collector, and I prefer jades in their perfect state. During my time of active collecting, that was before China's urbanization. Most jades were Shou Keng. I actually keep just a very small amount of jades sepcimen showing raised crystals. These were the jade speciment that I acquired in the latest stage of my collecting. The archaic jades that I collected over the years mainly are free of raised crystals. I found one or two small sporadic clusters of tiny raised crystals on a few pieces, but they are not fully-covered with raised crystals!

Thanks for the message will try and contact you when I get back to Hong Kong, now in deepest China and email hit and miss. Look forward to discussion with you.

Mike

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