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Fakes & FraudsClear greenish-blue "obsidian" from Brazil?

5th Oct 2008 17:17 UTCJeffrey Shallit

What do you all think of this item, just put up for auction on the Trinity Mineral Co. site?

http://auction2.mineral-auctions.com/item.php?itemID=9551

I've never seen rough obsidian this nice in this color. My guess is, probably bottle glass. What do you think?

5th Oct 2008 20:56 UTCRock Currier Expert

Yes, probably it has been cut from a chunk of man made glass. To have any credibility it would have to accompanied with a certification from the GIA or similar organization and even then I could be suspicious.

5th Oct 2008 23:48 UTCAlfredo Petrov Manager

I've never heard of any young volcanic rocks in Minas Gerais. Are there any?

Obsidian can only come from relatively young volcanic rocks, certainly nothing Precambrian or Paleozoic, because it tends to devitrify (crystallize) with age and lose its transparency.

6th Oct 2008 01:31 UTCJolyon Ralph Founder

Are we afraid to use the F word?

It's a fake!

Jolyon

6th Oct 2008 02:28 UTCChester S. Lemanski, Jr.

It looks like the material that was produced from fusing the volcanic ash at Mt St. Helens. It fuses to a clear glass of the same color. For a while it was marketed as spheres, eggs, and other shapes. This fact alone indicates that such a color of natural obsidian may occur, but I have never heard of, or seen any.

6th Oct 2008 03:35 UTCJim Houran

It's my understanding the Mt. St. Helens "fused" ash material is also fake. The ash can be fused, but apparently it doesn't produce anything gemmy. The fake material was commonly promoted as "obsidianite" many years back.

Thanks,

Jim

6th Oct 2008 11:17 UTCsteven garza

Dear Jim;

Sorry, "Helenite" is indeed VERY gemmy; it requires little more than slightly higher temp to melt than regular glass; but, it does. After it was done by promoters of this material, MANY locals did the same, with the same results. The gemminess or lack has more to do the how much "dirt" was scooped up, along with the ash, bcs, that didn't melt & mixed with the glass & stayed suspended.

Your friend, Steve

6th Oct 2008 13:59 UTCGuy Kronz

Hi all

I do agree to Jolyon it is a fake. I do have a turtle made out of the same material in my fake collection.

Regards from Luxembourg

Guy

6th Oct 2008 18:04 UTCAlfredo Petrov Manager

Argentine dealer Dr. Jorge Dascal has informed me that the same material had been offered to him and was alleged to be from "Paraguay". When the same material is alleged to be from two different countries (like the recent red gemmy feldspars), I get suspicious that something fishy might be going on.

Comparison with Mt St Helens glass is not really relevant. That is an artificial glass, not obsidian. Mt St Helens glass can't even be considered "artificial obsidian", because obsidian isn't melted volcanic ash anyway - different compositions.

1st Nov 2008 17:56 UTCEmory Coons

Hello I'm in the heart of obsidian central Eastern Oregon and seen over 250 different colors and verities and seen 5 translucent enough to facet 1 clear,2 brown, 3 yellow(sitreen color), 4 green(forest dark) and one from tri cities washington 5 lighter green almost moldavite color. Nothing like the one shown yet but i'm still looking

2nd Nov 2008 07:52 UTCJohn Veevaert Expert

As the owner of the auction site in question I usually make sure things are as they say they are by the dealers who post items to the site. First Luciana Barbosa is not one to try and hoodwink anybody. She is a fine dealer. Second as Emory points out obsidian occurs in myriad colors and hues. I have seen red water clear phases in otherwise jet black obsidian from California and Oregon, green from Oregon, California and Washington. The color ranges are beyond imagination actually when you consider what the stuff is. So... a fake. No. A genuine item of petrographic interest. YES. I am surprised at some of the posters on this thread actually....

2nd Nov 2008 18:07 UTCUwe Kolitsch Manager

Were there any tests done on this?

4th Nov 2008 00:50 UTCJohn Veevaert Expert

I received these comments fron Luciana Barbosa:

The mindat link you sent me made me deeply sad. I cannot believe I am at the "fraud and marketing ploys" for that. That piece is natural, I have sent all the information to the very person that started the forum. And then gave up, he would not give up his claim even knowing I had the stone checked at the Federal University of Minas Gerais.

I have been in the business for more than 20 years, I don't even deal with blue Topaz because it is irradiated. I will not post anything that might raise controversy ever again. I will save for gem shows to people that know me better than that, not people that acuse me for selling bottle glass... humiliating..

Again, I think that several of the people on this thread owe Luciana an apology. It is easy to toss verbal noise out there but sometimes the damage it causes is as irreversible as trying to put smoke back into a cigarette.

John

4th Nov 2008 03:35 UTCJustin Zzyzx Expert

I find it hard to believe that it is real too, but then again, the size is so small and good god I hate to admit it, but COLORED OBSIDIAN does occur as tiny specks in otherwise normal obsidian.

NOT that I'M any kind of roll model in this, but I do a lot of homework on cases of Fakes, to make sure they are indeed a fake.

Before jumping down ANYones' throat, you should make sure it is 100% true, or else you might just end up making a fool of yourself, which I'm also quite used to.

4th Nov 2008 07:57 UTCAymeric Longi

what a surprising thread ! Luciana Barbosa in the fake & fraud section ??? there's a mistake somewhere in !

If you guys knew the quality of her work and the insane variety of what she regularly offers, you wouldn't waste your time throwing rocks (can't be anything else in this place...) at her and instead would quickly grab this one, among many many others, rarity !

4th Nov 2008 10:01 UTCJolyon Ralph Founder

I'm afraid I still don't believe it's genuine. Extraordinary claims require extraordinary evidence, and a natural obsidian of this size and colour is, I'm afraid, a very extraordinary claim.

The only evidence we've seen is that the dealer in question is highly reputable, which I do not doubt, but then even the best of us can make a mistake at some point.

Jolyon

4th Nov 2008 10:25 UTCAlfredo Petrov Manager

John, There is no need to apologize to Luciana, because nobody on this thread has insulted her. I can attest that she is a very nice person with high quality material and reasonable prices. All that has happened is that a question has been raised about the true identity of one confusing specimen, which is a legitimate question to raise about any rock from ANY dealer at any time. And such questions should be answered based on the physical and chemical properties of the material, not by the reputation of the dealer, which is irrelevant to the question. I've seen misidentified material from even the very best dealers, too many times to count, and I've made enough misidentifications myself too.

So let's get back to the real questions: Where is this material from? Does that locality have recent volcanic rocks? What chemical and physical tests were performed? What were the results of those tests? We cannot base identifications on the reputation of the dealer, or on how much trust the dealer places in his/her suppliers, or on the say-so (without actual results) of anyone in the academic world... that would all be "theology", not mineralogy.

(Incidentally, obsidian is one of my favorite rocks, and I would be delighted if this material were to turn out to be true obsidian; i'm just a skeptic who requires more evidence.)

5th Nov 2008 15:17 UTCDavid Kobliha

It is natural. I have had pieces, and made them into polished pcs. Again not that common to find. I'm having one pc made for me I can send you an e-mail. It is a type of Obsidian that has formed this way due to intense heat (volcanic or otherwise). The call it Vidro da Terra in Brazil or translated to english Earth Glass.

5th Nov 2008 16:46 UTCJolyon Ralph Founder

Sorry that I have to say it again, but we need proof please.

Jolyon

6th Nov 2008 08:41 UTCDaniel Russell

Looking over the web, I see quite a number of examples of similar material being sold... as "obsidian", "glass", and "lab glass". The color is remarkably homogenous, without evidence of mottling or banding or tell-tale flow patterns oft-times seen in obsidian. One gem cutter notes on his website that "the consensus is that they are almost "too clean to be natural".

The material is being offered mostly as tumbled stones (suggestive that there is a significant volume of the material available, whatever its origin, and that the rough must be fairly inexpensive), limited numbers of faceted stones, calibrated sizes of "crystal balls" to 90mm, and medium sized carvings (to date I've seen both skulls and elephants). These larger items show the same homogeniety of color as the tumbles, which suggests that the homogenity of smaller cut stones was not so much a matter of judicious selection of rough as it is a gross property of the material in question.

Attributed localities of origin include:

China

Brazil

Indonesia

Vietnam

Mexico

"Africa"

Paraguay

A laboratory somewhere

Some is being marketed in the mentalfecesal world as "Aqua Lemuria" which one dealer states "is a rare type of Obsidian thats only found in the volcanic mountains of Sumatra an Indonesian island".

To quote R V Dietrich's web page on obsidian: ( http://www.cst.cmich.edu/users/dietr1rv/obsidian.htm )

A number of green gemstones, many of which have been faceted, have been marketed as green obsidian. Johnson, Reinitz and Owens (in Moses, Reinitz and McClure, 1998), however, report that "We cannot recall seeing an example of transparent 'green obsidian' that has ever been proved to be a natural obsidian."

Seeing an analysis of this material would be most edifying!

6th Nov 2008 09:39 UTCDaniel Russell

Does anyone know whether or not ALL air bubbles in obsidian show elongation or other distortion resulting from flow?

6th Nov 2008 13:22 UTCAlfredo Petrov Manager

Daniel, I can't answer your last question, but I have artificial glass with elongated bubbles caused by flow, so that would seem to be inconclusive.

6th Nov 2008 15:29 UTCJeffrey Shallit

I am sorry if people feel that I have insulted them. I simply posted an inquiry about the material. Perhaps it is indeed genuine - I have an open mind. I did not mean to impugn anyone's integrity; I simply asked for people more knowledgeable than I am to comment.

As for "he would not give up his claim even knowing I had the stone checked at the Federal University of Minas Gerais", this is not true, since I have not "claimed" anything; I have simply been skeptical and expressed my guess as to what the material is.

6th Nov 2008 15:42 UTCChester S. Lemanski, Jr.

Jeffrey,

There is absolutely nothing to be sorry for! You simply made an honest inquiry based on healthy curiousity. Look at the meaningful discussion that you instigated! There are a lot of data documented here now for all to peruse and make their own decisions of whether or not this stuff is natural or not. Personally, I think it is not, but that is just my opinion. As I mentioned very early on in the thread, the dynamic eruption of Mount St. Helens provided the first excuse for this type stuff to be marketed. It is surprising how consistent the color appears to be despite the attribution of occurrence to be anywhere from the NW USA, Brazil, Indonesia, Africa, etc., etc., etc. Great thread based on a great inquiry!!

6th Nov 2008 20:00 UTCUwe Kolitsch Manager

"... I had the stone checked at the Federal University of Minas Gerais."

I really would like to know who checked it by which methods...

7th Nov 2008 01:17 UTCDaniel Russell

Alfredo: actually I was thinking in the opposite direction, based on the following photo showing lovely big, round, happy air bubbles trapped in "Aqua Lemuria".... reminiscent of the bubbles you see on the periphery of a pot of man-made glass:

http://lemuria.tribe.net/photos/4f5a8f74-e761-417f-9eb5-072fe54a09b0

Interesting inclusions of what appear to be foreign objects in the material as well.

9th Nov 2008 12:37 UTCJohn Veevaert Expert

Hi Alfredo and the rest:

Had the original poster prefaced his remarks with an indication that Luciana was a dealer of the highest ethical standards it would have become a non-personal and informative thread. By insinuating Luciana was offering "Bottle Glass" as a faceted item of petrologic interest it created an impression of her as a huckster at some carnival. Had subsequent comments to original thread expressed what you said much further down the line Luciana's reputation would not have become an issue as it is now. That was my point. We all can and DO make mistakes. I have a few "trophies" in my curriculum vita.

Nature is astounding in what it offers us to gawk at. To cavalierly toss out a comment like this is a bit wreckless in my opinion. Anyone with experience in minerals and such has undoubtedly seen things that were hard to imagine as being real. Yet they are.

I believe a better way to handle something like this is to first privately ask the person who is offering the material to verify its authenticity. If the person is unwilling to go to that length then the next best way to offer it to an open forum is to simply cut and paste the image and ask the question without ascribing it to an individual. If the person offering the material in question is evasive or misleading then go viral with it. As it is now Luciana's reputation has been harmed by this forum.

I guess my question would be is that an actionable offense of slander? We should all be careful what we type in the comfort of our private homes on a keyboard. It can lead to unintended consequences.

9th Nov 2008 12:52 UTCJolyon Ralph Founder

John.

You are ABSOLUTELY out of line in suggesting that the original comment is slanderous, and I suggest you withdraw your remark if you want to EVER be able to post on this site again.

I know you want to defend your dealer friend, but please go back to the original comment.

Let me go back to the original comment:

"What do you all think of this item, just put up for auction on the Trinity Mineral Co. site?

I've never seen rough obsidian this nice in this color. My guess is, probably bottle glass. What do you think?"

How can you POSSIBLY consider this slanderous? It is an observation, and a question. The poster had never seen obsidian like this, and he thought it could be bottle glass.

Is that an unfair comment? No it is not, based on the comments of many other experts, they tend to agree there is a good chance this is not genuine. Even if the poster was wrong, it is not in any way slanderous, it is simply a question of scientific debate about an item that would be dealt with by a proper posting explaining the validity of the original sample.

We should NEVER take any dealers descriptions at face value. To start throwing accusations of slander against people for making what are, in my mind, totally valid questions as to the validity of a sample offered for sale is comtemptible, and looks entirely like an attempt to stifle a genuine debate. Individuals who do this, no matter of their standing in the mineralogical community, are not welcome as members of the mindat community.

You have 2 days to put this right.

Jolyon

10th Nov 2008 12:11 UTCJeffrey Shallit

John Veevaert wrote:

"Had the original poster prefaced his remarks with an indication that Luciana was a dealer of the highest ethical standards it would have become a non-personal and informative thread."

I don't think I could have written that fairly, because I didn't know anything about Luciana or her reputation at the time. Again, I simply posted the item as a query, with no insinuation at all about anyone's reputation. If others assert that Luciana's reputation is above reproach, I'm happy to accept their verdict, and to apologize again if anyone thinks I have insulted her.

Now how about an apology to me, because it is simply not true that I "would not give up his claim even knowing I had the stone checked at the Federal University of Minas Gerais." In fact, I relayed Alfredo Petrov's comments to her and she thanked me for them. This is what she said in her last e-mail to me: "I can't thank you enough for alerting me." There was no indication in any of her e-mail messages that she was unhappy with me.

10th Nov 2008 14:13 UTCJohn Veevaert Expert

Hi folks - before everyone comes out of their skin I wrote the comments at about 3:30 am dealing with jet lag from the recent trip to Munich. Not an excuse but a factor. After reading my post I can certainly agree it came off a bit harsh. So for that I do apologize. What the last comment of concern should have read was:

I guess my question would be is that an actionable offense of slander? I DON'T KNOW? PROBABLY NOT.

What I was only trying to convey is that words we write in these bulletin boards can be hurtful to people and bring into question the ethics of the dealers involved. Luciana was deeply hurt by this thread and that is ALL I was trying to convey with my comments. I do apologize to anyone who felt offended by my comments but I do hope everyone will consider a different way of dealing with issues this in the future. No one is rounding up a legal team I assure everyone.

And with that this will be my last post to Mindat.

All the best to everyone, John

10th Nov 2008 14:54 UTCJolyon Ralph Founder

Thanks for your comments John, I'm sure you realise why I had to take your message very seriously and react in the way I did.

No-one is singling out Luciana for this, in fact, her name was not mentioned on this thread until you mentioned it!

It's absolutely clear that our issue is about the material identified, not with the dealer in any way. I'll make it clear in case it wasn't, that even if this material is proven to be artificial glass, there is no reason to think in any way that Luciana had knowledge of this and was in no doubt offering the material in good faith. No-one can be an expert in everything.

But, the material is still regarded as suspect, and debate of it is highly important. A brief google search shows there is a huge amount of this material offered from various places such as Indonesia and Brazil, far too much for it to be regarded as a unique and exceptionally clear piece of natural obsidian. In the absence of any proven natural origin for such a material (which presumably would have made a very interesting and important scientific paper), we have to assume it is artificial unless proven otherwise (and my understanding is that you can't prove for certain something like this is natural by scientific tests although you could probably prove it was NOT by analysis of impurities - the only proof would be to see the natural material in situ).

Anyway, hope you had a great time in Munich, sorry we didn't get to speak for more than about 5 seconds, and see you in Tucson.

Jolyon

11th Nov 2008 08:29 UTCDaniel Russell

From the webvert of one of the distributers of "natural obsidian" in Indonesia:

"Rough Obsidian" available in "Khasmire blue, Aqua blue, Sky blue, Dark blue, Green, Light green, Brown, Light brown, Black, Red, etc "

http://img.alibaba.com/photo/11619061/Rough_Obsidian.jpg

http://img.alibaba.com/photo/11885108/Obsidian_Polished.jpg

http://img.alibaba.com/photo/11779223/Obsidian_Simple_Cutting_For_Earring_And_Pendants.jpg

And most interesting of all:

http://img.alibaba.com/photo/101152918/Natural_Obsidian_Stone_In_Rough.jpg

8th Dec 2008 03:09 UTCRock Currier Expert

Daniel,

Those were great pictures of "natural obsidian" especially the one the last one. It is so tempting for con artists to try and sell glass off as a natural stone. The temptation is to much. You pay $60 per ton and turn it into $60 per carat material. The stuff of made all over the world at various glass factories and has been for nearly 100 years? Pieces get buried in gradients and land fills and when it gets dug up it obviously is now a naturally occurring rock, right? And naturally occurring rock like this is definitely obsidian? Right? The stuff is ubiquitous and fraud abounds. So naturally knowledgeable people must be very skeptical about such things and it is reasonable in such cases to demand rigorous testing to prove that it is natural. I think that it is more than reasonable to ask Luciana who at the Federal University of Minas Gerais did the testing and ask them to describe the tests performed. It may be that the University has very find and competent analytical facilities and very knowledgeable mineralogists and gemologists there to check things out, but I have not heard that they do. I think it is also reasonable to ask for the locality from where such material is found and if any knowledgeable people we know can verify is such things come from there. Even if Luciana and John did screw op on the identification, so what? If they did I don't think anyone believes it was intentional. Is someone worried about not getting their money back? Who among us has not screwed up? All of us have screwed up. But, who at the University made the ID and what methods did they use? Why is that information not forth comming. It would take a lot less effort to produce this information than all this unnecessary verbiage.

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