Post subject: Aquamarine blue obsidian - does it exist?
Posted: Sun Oct 23, 2005 6:22 am
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Joined: Sun Oct 16, 2005 12:42 pm Posts: 2846 Location: Ho Chi Minh City, Vietnam
I was in a mineral and gem shop this past summer , and the people who owned it were selling beads and jewelry of what they had been told was obsidian. The lady wasn't sure of the origin and was waiting for more information on it from her dealer. I have also seen the same being sold as aquamarine in Turkey.
Hello,
I never heard about this color to be a natural color, and then I dont have seen anywhere on this page that this piece of glass is supposed to be natural... So it is probably not natural.
The views expressed here are V. Pardieu’s opinions and do not necessarily reflect those of GIA Laboratory Bangkok (http://www.giathai.net)where he is an employee since Dec 2008.
Joined: Sun Oct 16, 2005 12:42 pm Posts: 2846 Location: Ho Chi Minh City, Vietnam
The page showing the picture lists it as lab glass.
The lady in the store this summer said that her dealer had claimed it was obsidian, but she couldn't remember where it was supposed to have been from. She thought maybe China, and was waiting on more information about it from her dealer.
I doubt very much that it is natural as well, since it was very very clean, although I have run across a reference on the internet to "green/blue obsidian" qualified with "not sure if it's natural or not".
Joined: Sun Oct 16, 2005 12:42 pm Posts: 2846 Location: Ho Chi Minh City, Vietnam
From the GemCutter site:
Quote:
The following pieces were sold to us as obsidian from China. Their SG and RI are consistent with natural glass, and I have consulted with other gemologists on these: the consensus is that they are almost "too clean to be natural", but there is every other indication that they are natural, which means they fit a very narrow range of physical characteristics common to natural glass that is very difficult to duplicate with manufactured glass. The GIA does have record of blue obsidian, so we have found no reason to dispute the claim that they are natural obsidian.
The stuff that I saw looked exactly like the lab glass in the first link that I provided. Maybe the blue obsidian that the GemCutter people are referring to above "GIA does have record" isn't the same colour of blue?
I would say it is almost certainly glass, not Obsidian. It is far too clean in that massive size to be obsidian, and I have never seen it blue either. But cheap all the same for a facetor who wants to practice cutting whoppers.
I also agree with Vincent – that even if it was obsidian, it is a mineraloid - not a mineral, and although in it's natural state can be interesting, as a gem cannot really be differentiated from cut glass, in beauty, durability or value.
_________________ I always arrive late to the office, but I make up for it by leaving early...
Oddly enough yesterday a client walked into my office with a suite of blue obsidian. A large faceted octagon an a smaller matched pair. I have never seen it before but I recalled this thread.
The stones were pretty much aquamarine blue with a bit of gray mask. They were quite clean, loupe clean.
Nuck,
These were darker in tone and not at all greenish. Don't know the source as the client really had no idea. Given its composition seems like obsidian should be available (theoretically) in any color.
The stones were for sale though I didn't ask the price. For me Obsidian ranks right up there as a gemstone, maybe just behind copralite. If you are interested I could enquire.
Joined: Sun Oct 16, 2005 12:42 pm Posts: 2846 Location: Ho Chi Minh City, Vietnam
Well, I should be back in Corsica at Easter, so I will definately go and ask this lady if she got more information on it or not.
I'm not really looking to buy any, I'm just really curious to know if there is really such a thing, or if this is some dealer passing lab glass off as obsidian.
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