At the World Gem Society we believe the only viable method to locate and study new gemstone treatments is to go out onto the open market and purchase gemstones in what we call “blind buys” where the dealer is not aware of our study. Otherwise, allowing dealers to simply supply specimens for study allows the dealer to clandestinely influence the study. This does not provide for a true test of the current market conditions.
Recently, the WGS purchased an additional 200 specimens of rough and faceted aquamarine from a variety of dealers from several world locations. Virtually all of the stones we obtained showed no indications of treatment, except those from two sources….Thailand and China. In the banner image above you see what we first saw when inspecting these stones: a damaged thread encased with a glassy material and glazed onto the surface of the aquamarine. If this looks to be strangely familiar to our recent study of Inner Mongolian and Tibet andesine, you would be correct. The same glazed surface containing damaged threads encased in glassy glaze, the same as we found on the Chinese andesine.
We applied our inspection protocol that we established during our expose’ of the Chinese andesine fiasco and found remarkably similar, if not exact, features on the Thai and Chinese sourced aquamarine rough as we found previously on the Chinese andesine rough.
But then the unexpected happened……
Below is a high magnification image of one of the glazed threads. The damage and glassy crust is obvious. But the strange feature we realized about this image was that the upper end of the thread is actually inside the crystal. Not glazed to the surface, but actually is encased inside the crystal itself. That was a very strange situation that was totally unexpected. We had previously found these surface glazed threads on the Chinese andesine, but to find a thread actually going inside the crystal created an anomaly.
By going to a lower magnification we found the answer and it was quite unexpected.
Below is a lower magnification view of the same stone. Look just to the center of the image, and notice the curving white line. That is not an internal fracture. That is an internal thread! This aquamarine has a thread inside the crystal.
Our question: How is that possible?
Using our Meiji Techno microscope and Canon XTi SLR, we were able to capture an image of this thread and realized exactly the nature of the thing.
As you can see at left in this contrast enhanced image, this is a damaged thread just like those we found on the surface of other Thai and Chinese sourced aquamarine crystals, and previously on the surface of the Chinese andesine. Yet this is inside the crystal.
For comparison we offer an image of a thread in the same condition from the surface of the Litto Gems specimen seen in our previous report on Chinese andesine. This can be seen below.
Note that the thread appears split into two, but is instead simply damaged by apparent heat and pressure. The only difference is that the thread of this aquamarine seen at left is actually inside the crystal, encased in the glass filler that has been used to treat this aquamarine.
By backing off the magnification, and using overhead lighting, we were able to verify that this aquamarine demonstrates the same glass filled treatment as the previously seen glass filled rubies and sapphires. The surface offers the same glazed glass material that we have previously confirmed as being a formation of sodium silicate known as “water glass”. Below is a 10x image of a glassy surface area.
Below is a comparison of the feature above to a known glass filled green sapphire crystal that we obtained from a Hong Kong sapphire dealer.
By Raman scan we confirm that the glassy material is the same on both specimens, and that these both match our control scans of “water glass”.
We also found that this glassy surface glaze with encrusted threads was remarkably similar to the Chinese andesine from our previous report. The formation of the glassy glaze on the surface including the presence of damaged threads is virtually identical, with the exception of the color of the gemstone crystal and threads.
Although the specimen shows a nice uniform body color in ambient light, through our infamous Dixie® Cup immersion cell we were able to verify that the regions of this crystal that contained the glass filling also contained color zones that exactly matched the glass filled zones.
Image at left is at 10x through our Meiji Techno microscope using a Dixie cup immersion cell and tap water from the San Antonio water system.
Upon inspecting other stones in the immersion cell we found the same situation on other specimens in our collection as seen below. It should be noted that these stones did not show visible color zoning in ambient light, and not all demonstrated such pronounced features through the immersion cell.
Given the many similarities to the treatments found on Chinese andesine, it was no surprise to find the features shown in the image seen at left.
Based on our previous research on the issue of annealed graphite on the Chinese andesine, we were able to confirm by Raman that this is indeed annealed graphite on the surface of this aquamarine. This material is hardened onto the surface and is of the same form as that found on the Chinese andesine and in our control specimen annealed graphite crucible
This specimen above is quite literally aquamarine on one end, and annealed graphite on the other end. The annealed graphite end shows signs of having been originally in contact with other objects. This area provided a clear location for Raman scan and by comparing that to the Crystal Sleuth we confirmed graphite as the identification.
Based on our previous research on the unique peak of annealed graphite, we were able to verify this to be annealed graphite….heated to a very high temperature at some point on this crystal.
Below is a high magnification view of another area of annealed graphite that has partially melted into the surface of this aquamarine.
While there is much that we do not yet know about the specific elements involved, the glass filled status and the color infusion of these specimens is without question. The glassy surface duplicates exactly the features in the glass filled rubies and sapphires, including the identification of this material as “water glass”. The damaged threads glazed on to the glassy surface precisely duplicate the features found on the treated Chinese andesine. And the identification of annealed graphite melted onto and into the surface of these specimens can only be explained by some sort of relic from a crucible as per our previous work.
When we factor the above in to the color infusion zones present in these specimens, the only reasonable conclusion is that someone in Thailand or China, or both, is using the same type of treatment on aquamarine as was previously found to be successful on feldspar.
We have confirmed this treatment on other gemstones as well. That report will be forthcoming.
World Gem Society
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