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PostPosted: Mon Mar 16, 2009 5:42 pm 
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Barbra Voltaire wrote:
And exactly how would that be done, gsellis?

I don't remember if there are new steps anymore, but the methods I remember are not kind to the material (destructive). There is a centrifuge method that they use to create weapons material with. The other one involved a particle accelerator and generated a spectrum where the atoms fell. New spectral analysis, I do not know.


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PostPosted: Mon Mar 16, 2009 5:49 pm 
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If you look at the original cease and desist letter from the DSN lawyer, they specifically only asked RJ and ISG to stop claiming that the Olympic andesine was originally from Mexico. They never mentioned treatment or diffusion at all.


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PostPosted: Mon Mar 16, 2009 6:17 pm 
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I raised the issue of tourmaline with Dr. Rossman. I was curious as to his take on the famous goop in the tubes. He was not surprised that lateritic material would have found itself into open growth tubes or that it would bake on hard after heating. However, when I asked him about the magnetic properties of hematite and limonite (bog iron). He said the neither is particularly magnetic. That is, neither would be likely to stick to a magnet.

You recall James' magnetism images showing "goop" sticking to a magnet? Here is a curious anomaly. Iron in the flux used in the heating crucible would explain it, but it does raise a question.

Wonder if James' was a neodymium magnet. Anyone have an answer?

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Last edited by Richard W. Wise on Mon Mar 16, 2009 7:45 pm, edited 1 time in total.

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PostPosted: Mon Mar 16, 2009 6:27 pm 
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More later. :)

http://van.physics.illinois.edu/qa/listing.php?id=357

Here is an interesting article by Dr. Rossman from 1983


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PostPosted: Mon Mar 16, 2009 7:16 pm 
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Richard W. Wise wrote:
P.S. Not that I doubted you Barbra, but when I am researching for a possible post I always try to talk directly to the source rather than relying on secondary sources and I was very curious to find out if Dr. Rossman was a GO aficionado. He apparently is!

No worries. I appreciate reinforcement and I always like to double and triple check to make sure I'm not getting something wrong. I was all prepared to take copious notes at the lecture, but since I was sitting next to the Power Point projector, I volunteered to be in charge of clicking to the next page.
I couldn't write and click at the same time, so I had to commit everything to memory :shock: .
Therefore, it was entirely possible that I put a little spin on my first draft.
I've rewritten it 3 times.
I think the one I finally posted here is spinless. :wink:

PS I'm very much looking forward to reading YOUR article, Richard.


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PostPosted: Mon Mar 16, 2009 7:56 pm 
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Barbra,

Have to say I am getting awfully tired of this issue. My specialty is aesthetics. You, along with Bear and several others, know a good deal more about the science than I do.

I am constantly amazed by the level of knowledge exhibited by the members of this forum. I have never owned a piece of andesine and honestly, the only reason I took this on is that it seemed like no one else would come right out and publicly challenge James' and Federman's nonsense.

I am just a humble grass-roots jeweler working my way through life. Talking to Rossman only added to my humility.

I believe at this point GemWise has a larger audience circulation than Colored Stone. I would love to get a few of you all to join the GemWise team and publish an article.

Best,

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PostPosted: Mon Mar 16, 2009 9:13 pm 
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Richard W. Wise wrote:
I raised the issue of tourmaline with Dr. Rossman. I was curious as to his take on the famous goop in the tubes. He was not surprised that lateritic material would have found itself into open growth tubes or that it would bake on hard after heating. However, when I asked him about the magnetic properties of hematite and limonite (bog iron). He said the neither is particularly magnetic. That is, neither would be likely to stick to a magnet.

You recall James' magnetism images showing "goop" sticking to a magnet? Here is a curious anomaly. Iron in the flux used in the heating crucible would explain it, but it does raise a question.


Hi Richard,

Oh yes, the proverbial reddish colored goop in the tubes. A lot of material especially hematite occurs naturally along with tourmaline as we all know. We see that this material can easily be attached to tourmaline either on the outside or stuck in the hollow tubes.

You mention baking which is exactly what happens when they heat the tourmalines to induce the color change. According to Dr. Johnson, when the hematite is attached to the tourmaline, it's the baking process itself that causes it to display higher susceptibility to being drawn to a magnet.

I've seen hematite beads sold for thier magnetic qualities, but we have to clarify that while hematite is not neccesarily magnetic, it can be quite attracted to magnets. And apparently especially so if it has gone through a heat treating process for the stone it may be attached to.

Bear


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PostPosted: Tue Mar 17, 2009 3:36 am 
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Barbara - Thanks for the great report!!

I wanted to clarify the stuff about K-Ar ratios. The feldpars do not acquire Ar from their surroundings; it is generated within the feldspar itself. There is a lot of K in feldpars when they form. A certain percentage of this (0.0117%) is radioactive 40K, which over time decays to either 40Ca (89.1%) or 40Ar (10.9%) with a half-life of 1.248 billion years.

Because Ca is a constituent of feldspars, it's hard figure out how much of the currently measureable 40Ca was initially present in the feldspar when it formed.

However, Ar is not a constituent of feldspar, so it can be assumed that the current measured 40Ar content represents Ar that formed in the crystal after it became "closed" to Ar diffusion by cooling below the "closure temperature". The closure temperature, in this case, is the temperature below which Ar diffusion through the feldspar lattice effectively stops (K-feldspar ~230 C, plagioclase ~176 C, microcline ~132 C).

Given these and other constraints, it is possible to determine how much time has passed since the feldspar crystal cooled to beneath the closure temperature, assuming that the system has not been disturbed. (For more information on the details, see for example, Principals of Isotope Geology by G. Faure). It it likely that feldspars from different geographic locations would have different K-Ar ratios because they probably formed at different times and experienced different geologic histories.

You many have noticed that the closure temperatures for Ar in different feldspars are quite low. This means that some geological processes (and even treatment processes) can disturb or "reset" the Ar clock by heating up the feldspars enough to allow Ar to diffuse out of the crystal lattice. (Or into the lattice, if treatment occurred using an Ar atmosphere. This gas would, nevertheless, have a different isotopic signature than the feldspar Ar, and thus might be discernable.)

Even if the system has been disturbed, there are still a lot of interesting things that you can discover by studying the K-Ar ratios in samples. I assume these considerations will be part of the work published by Rossman and colleagues. I suspect that they have a paper either in submission or at least almost ready for submission, since they are now reporting results at conferences. I'm looking forward to it!


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PostPosted: Tue Mar 17, 2009 7:09 am 
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Bear,

Thanks for the reply. As I said there are a number of people on this forum who know far more than I do when it comes to the science.

Most opal diggings in the Queensland outback are open cut. The soil consists of layers of lateritic clay juxtaposed against sandstone. When the layers are cut open by a bulldozer they are quite soft, but after a few months in the hot Australian sun, the material bakes literally hard as a brick. The miner's call it "shincracker".

Cheers,

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PostPosted: Tue Mar 17, 2009 11:14 pm 
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If I might be so bold as to speculate about the supposed "Tibetan" material.

1 - Buddhists prefer materials that are collected from the surface rather than wrenched from the earth, so a mine would probably have been a Chinese creation.

2 - I would suspect with all the attention on China's poor treatment of Tibetans, that they used that as a political "marketing ploy" for the Olympics, if the material does in fact come from the Mongolian area.

3 - The pictures of the Tibetan "mine" I saw didn't look like it had actually been used - the area outside showed little sign of activity other than creating the hole, in my opinion.

But I just buy stones and hope they are worth something approaching what I pay for them - and wish some of the incredible knowledge of the people contributing to this forum rubs off on me.

Thank you for all the amazing information.

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PostPosted: Wed Mar 18, 2009 8:59 am 
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Hello Empress,

I appreciate your comments & observations and suggest everyone feel bold enough to voice their views or speculations as long as they are done without malice. I also speculate on your thoughts with my opinions:


---------
If I might be so bold as to speculate about the supposed "Tibetan" material.

1 - Buddhists prefer materials that are collected from the surface rather than wrenched from the earth, so a mine would probably have been a Chinese creation.

Do you feel like this might be a generalization? I know plenty of Buddhists that are happy to wrench things from the earth. True, they are pacifists but you should see some of the mines they work. They do need to make a living. And Chinese can also be Buddhists, no? Yet it seems you are right in that the owner of that mine is Chinese, having just met him in Tucson.

2 - I would suspect with all the attention on China's poor treatment of Tibetans, that they used that as a political "marketing ploy" for the Olympics, if the material does in fact come from the Mongolian area.

That could be a possibility. I'd not seen where it was advertised as such though. Chinese can size up opportunity fairly quick, but I feel it's probably always been just about the money and doubt that the gov't is involved.

3 - The pictures of the Tibetan "mine" I saw didn't look like it had actually been used - the area outside showed little sign of activity other than creating the hole, in my opinion.

Good observation. I also hold reservations on the legitimacy of that operation. I feel there are still things that need to be revealed by those producers in China. If it reaches the international level of accountability and serious fraud has been commtted, then there could very easily be heads [literally] chopped off. I would not want to be responsible for any part of that however.... bad Karma.

Regards, Bear
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PostPosted: Wed Mar 18, 2009 9:27 am 
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By the way, it wasn't the Chinese who were marketing andesine as the Olympic stone. DSN did that. In order to get that you work through the Olympic committee and get permission (for a fee I'm sure) to call whatever it is you are selling the "Official Olympic [whatever]".


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PostPosted: Wed Mar 18, 2009 11:33 am 
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I want to reinforce what Bear said.
I encourage ALL views on this forum.
If you have an opinion that is completely the opposite of mine, or another member, chime in! Be heard!
The only request is that we treat each other with a respectful tone. :D


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PostPosted: Mon Mar 23, 2009 2:10 am 
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Magnets, minerals, and simple science :D


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PostPosted: Mon Mar 23, 2009 12:51 pm 
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Ferrofluids are awesome.


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