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Have the reverse-skeletal Madan galenas been faked?
Posted by Patrick Haynes (2)
Rob Woodside March 01, 2010 01:26AMI recently had the oportunity to loop some of these cavernous galenas at Tucson. The pock marking from the air abrasive is quite noticeable at 10x!!! I'm told that Mike Rumsey is going to get some backscatter SEM photos of this material that should put this matter to rest.
Robert Simonoff March 01, 2010 03:26AMJessica found this in Tucson this year. She photographed it specifically for this discussion. It shows one of these galenas with quartz poking through the hole. I am not saying this solves the mystery.
Edited 3 time(s). Last edit at 03/01/2010 03:55AM by Jessica and Robert Simonoff.
Ariel S Wall March 04, 2010 07:00PMIm new to the debate, but these specemines look highly etched with some type of acid. Could someone have"painted" on a sealant to protect the galena edges early before etching,with the purpose of cleaning them up and removing the oxides and such. In doing this they possibly inadvertantly dissovled away the centers of the galena cubes and just went with it. It does look like a byproduct of acid cleaning. What sealant would protect the edges of the galena to acid but later be able to be removed after with another chemical?
Alfredo Petrov March 04, 2010 09:42PMThanks for the photo, Jessica!
What the quartz shows us is that the galena is younger, in other words the galena grew over the quartz crystals, which were then hidden inside the galena as inclusions, to be revealed again after the galena was etched away. Whatever etched away the galena, whether mechanical or chemical, natural or artificial, did not attack the quartz. So, unfortunately, the quartz doesn't help to answer the question of whether the peculiar holes in the galena are natural or artificial. If you can find a less tough mineral inside the galena, like calcite or sphalerite, that would pretty much destroy the "manufactured by microabrasive" theory. Keep looking!
Rob Woodside March 05, 2010 06:13PMThere could well be damage to the quartz from the air abrasion, if they used anything hard like glass beads.. What has been frustrating about this thread is that there are no photo micrographs of this material. They would clearly show the pitting I saw with a 10x loup on the several specimens I saw at Tucson.
Knut Eldjarn March 05, 2010 09:00PMWhen we met in Tucson Alfredo mentioned seeing a specimen of these Bulgarian galenas with remnants of "clay" inside the hollow galena-cubes. A SEM-picture should be able to tell if there was remnants of a abrasive material in the "clay". Any news on this, Alfredo ?
Alfredo Petrov March 07, 2010 05:42AMNo, Knut, no analyses done yet on the white residue, as far as I'm aware.
And Rob, I've seen lots of quartz crystals cleaned with glass beads and they don't show any damage. The 5 - 7 hardness difference is significant. Perhaps impact by glass beads would leave marks visible by SEM?
Marcus Voigt March 07, 2010 09:55AMHello,
The last 10 years I specialized in collecting bulgarian Minerals.
I saw a lot of interesting Specimen,mostly from the Madan-Laki Region in the Rhodopi Mountain.
"Mother Nature" is the best artist on this Planet, but in my opinion ,in this case we have a good hand-made job!
A "normal" salary in Bulgaria is between 200-400€. Its too much to die and too little for Life.
Maybe this year I have the chance to meet the artists of this ......and here goes my respect to this very talented bulgarian people.!
Alfredo Petrov March 10, 2010 10:19PM....then we'd be discussing digital alteration of video instead of alterations of minerals ;-))
And as for SEM analysis of surfaces to check for abrasive marks, I'd think it would be easy to remove those by etching with HNO3 after the mechanical treatment. There really isn't much that Nature can do that humans can't duplicate. (Although the reverse is not true, at least not on this planet.)
Edited 1 time(s). Last edit at 03/10/2010 10:24PM by Alfredo Petrov.
Ariel S Wall March 11, 2010 05:40AMWell like I asked before is, could someone paint on some type of selant to protect the edges of the galenas then chemicaly etch them? Then remove the sealant off later with something else preserving the terminated edges? No mechanical just chemical etching.
Jeff Weissman March 11, 2010 03:45PMTake a look at http://www.mindat.org/photo-283163.html for an example of a naturally etched mineral, albeit in this case pyromorphite microcrystals. Clearly these crystals are chemically zoned as revealed by distinct variations in color, with a layered structure, better seen in http://www.mindat.org/photo-282700.html. It is my belief that slight differences in solubility, due to this chemical zoning, resulted in selective etching of these pyromorphite crystals, resulting in the unusual shell/tubular morphology due to the outermost layer, by chance, being the least soluble. (btw, softness of images due to just getting acclimated to using image stacking, may remake these images in the future). Same behavior in vanadinite, from the same locality: http://www.mindat.org/photo-282702.html
As suggested in prior posts, selective etching of chemically differing zones, in the galena, could result in the observed morphology. However, subsequent cleaning of these specimens have unfortunately removed any indications of a natural origin.
Or, someone with too much time on their hands, and access to a portfolio of M. C. Escher prints for inspiration, has made these. You can etch with sand blasting, or using a microsyringe, apply liquid drop-by-drop, on each face, with a suitable liquid with wax coatings in areas to be protected.
I have read nothing in any of the prior posts that is conclusive one way or the other. I would prefer that the source supplier bear the burdon of proof - show us one that has not been cleaned and clearly indicates its natural origin.
Edited 2 time(s). Last edit at 03/11/2010 03:49PM by Jeffrey Weissman.
Andrew Tuma April 24, 2010 06:23AMJust to keep this discussion rolling, I have a little more information to add.
I was able to purchase the specimen highlighted by Ken Doxsee earlier in this thread with the galena crystals with the dimples shown in the centre of the crystals.
Even though most of the crystals showed dimples, one was hollow as the photographs show. Interestingly the hollow crystal continues under a solid galena crystal. This would be very difficult to produce mechanically and why only do one when the rest are dimpled. It can be noted that in one point a crystal has a small hole that opens into a larger cavity within the centre of the crystal. I think that the dimples are the last stage of growth not the first stage.
Closer investigation does not show any mechanical making under magnification. Another interesting aspect are the growth layers on the galena crystals, also shown on the photographs. Similar growth structure is noticeable on the chalcopyrite and Sphalerite crystals on the same specimen.
I can not speak for the other skeletal examples discussed but I would strongly suggest this specimen has naturally developed.
I am surprised at some comments that imply that when a specimen looks like a fake then it must be a fake, sorry but nature does not work that way. I have spent enough time field collecting to know when unusual elements combine with out of the ordinary environments then very unusual mineralogical outcomes sometimes occur. I suspect this is the situation at Madan ore field with some of these galenas'.
Matteo Chinellato April 24, 2010 08:24AMthis is a good example seen from near
Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)
Jolyon & Katya Ralph April 24, 2010 12:34PMI'm not sure what you mean Matteo, but at the prices these specimens are selling for it should be very economical for someone to use a small drill (such as a Dremel) and spend some time sculpting them.
Maybe someone can do an experiment to try this?
Matteo Chinellato April 24, 2010 02:41PMthe piece I have take the photo its sale for 400 euro, few if a person lost time with a drill for build a fake
Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)
Jolyon & Katya Ralph April 24, 2010 11:16PMIf they're genuine why hasn't someone done an article somewhere about their unique form? I'm not using that as evidence that they're fake, but it would really go some great way to convincing me that they aren't.
I'm not convinced they are fake, but I would like to be convinced they are genuine, and nothing I've seen so far has done this.
Unfortunately nowdays you have to learn to be VERY suspicious. I just saw some photos that show a tourmaline crystal in albite matrix, the hole for the crystal was carved based on laser measurements of the crystal so it's a near-perfect fit. From the photos you could never tell it was faked. When there is serious money involved the temptation for criminal activities is sometimes too strong.
Andrew Tuma April 25, 2010 01:52AMI do not have any doubt that the one I featured is natural but it does also not show the extreme skeletal structures noted in some photos.
So likely scenario is that naturally forming hollow/skeletal growth was noted within the deposit and an opportunity to enhance the financial returns for the specimens available was understood and a faking procedure was implemented that ended with highly enhanced skeletal galena specimens. This likely means that that there will be both natural and enhanced (fake) specimens from the same deposit within the marketplace. A real problem for buyers which really means that extra care must be applied before purchase due to very acceptable levels of suspicion.
For interest, I also ask the question is it a true fake ( mineralogy not from a location) or an enhancement similar to polishing the face of quartz crystal or cutting a new termination to remove an imperfection. The Galena crystals clearly occur naturally on the matrix provided with associated Quartz, Chalcopyrite and or Sphalerite but are provided with man made changes.
This might be the very problematic issue for the future, where specimens are "touched up" to maximise the level of perfection to obtain the highest financial return rather than blatant fakes of manufactured specimens. This might mean we have to carefully look at every termination for damage if the specimen is too perfect. With improved technology and increased mineral prices, the chances of "enhanced" specimens being in our collections increases in the future.
The result this situation is that we again appreciate and will accept a few chips and marks as this level of "imperfection" may guarantee authenticity as it is not perfect a perfect specimen. (Food for thought and another thread!!!).
The enhancement issue may become a bigger problem and provide a greater level of fraudulent activity that the obvious faking we see now.
Matteo Chinellato April 25, 2010 04:37AMfo build a fake tourmaline you have to take few time, a hole in the matrix, some glue et voilà, I have seen many Elba tourmaline sell for original when the crystal its from pakistan and the matrix from Elba or viceversa, nicest is you find this material actual in the Elba mineral shops if you go in the island.
Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)
Stuart Mills April 25, 2010 04:47AMJolyon Ralph Wrote:
> If they're genuine why hasn't someone done an
> article somewhere about their unique form? I'm not
> using that as evidence that they're fake, but it
> would really go some great way to convincing me
> that they aren't.
Radostina Atanassova (2005) PhD Thesis: Hydrothermal minerals in highly non-equilibrium conditions: Morphology and crystal growth of hydrothermal sulphides far from the equilibrium. Bulgarian Academy of Sciences, Geological Institute.
Jolyon & Katya Ralph April 25, 2010 12:24PMStuart - Does this PhD thesis SPECIFICALLY discuss the hollow cube forms we are talking about? I checked previously papers from her and others in Bulgaria relating to galena forms and although there are many disucssions about the other weird forms of Galena, there was no specific mention of these holllowed cubes.
Carl Sagan was fond of saying extraordinary claims require extraordinary evidence. These hollowed cubes are certainly extraordinary. It's just scientifically WRONG for us to assume these are natural until proven false. Aren't we meant to be sceptical in science?
Andrew Tuma April 26, 2010 08:35AMThanks Stuart for that info,
This might be one of the most anticipated pieces of mineral literature for some time.
Stuart, are you able to ask your contact if this PHD thesis will be released in an english version and when it will be available.
I get very interested when the unusual mineralogical environment produces weird specimens, must be from having a few oddities in my backyard of Western Tasmania.
Anatoly Kasatkin April 26, 2010 03:43PMI agree with Stuart. As well as many russians who saw these samples in person - we are pretty sure they are true.
At Munich show last year I saw several samples with tiny quartz clusters attached to a hollow galena
cubes in their interior walls. Apart that they looked absolutely natural (we carefully studied them under the scope), I can also hardly
imagine someone who would need to fabricate the hollow and then glue quartz on the walls. I discussed this with many bulgarians at
the show whom (this is important) were not so friendly towards Ivan Pojarevski who was the only dealer to sell these so their
opinion is certainly not prejudiced. Nevertheless, they were sure these are not fakes though the real locality of these samples
was a real enigma for them either.
Yesterday we looked at these again with Igor Pekov and he is sure they are natural either.
Weird, unusual and (often) very aesthetic doesn't necessarily mean a fake.
Also I don't see any direct relation between the existence of something mineralogically interesting and the absence (maybe temporary) of its description in the scientific litterature. Zvyagintsevite at Kondyor is unique, not really described so far but it's not a fake (even if Pavel successfully built one in his lab!).
Lyla J. Tracy April 26, 2010 05:44PMI have followed this thread with great interest and have some questions.
Is a specimen considered fake until proven natural?
If a specimen has an unusual morphology does that place it in a category of suspicion?
If a specimen can be created by human hands does that prove similar specimens to be fake?
Does the stated country of origin, the price or quantity on the market, and or the dealer/seller's origin have a bearing on the "validity" of a specimen?
Jolyon & Katya Ralph April 26, 2010 05:58PMHi lyla, I'll give you my answers
> Is a specimen considered fake until proven natural?
Everything should be considered fake until you have convinced yourself otherwise. In many cases a cursory glance will tell you that it's genuine. But even then first looks can be deceptive. Should we regard everything uploaded to mindat as a fake unless we've personally examined them? No, probably not. But it's healthy to have a certain level of distrust, especially with specimens of value.
> If a specimen has an unusual morphology does that place it in a category of suspicion?
Not on it's own, but it can lead to doubt and the need to investigate things a little more thoroughly.
> If a specimen can be created by human hands does that prove similar specimens to be fake?
No, it doesn't. Human processes can replicate natural processes (hydrothermal quartz crystals, for example). But we do have to use common sense. Most copper sulphate ("chalcanthite") crystalline specimens are artificially made. That doesn't mean that every chalcanthite crystal out there is fake, but when you are examining these crystals you are automatically assuming they are fake and needing to convince yourself otherwise.
> Does the stated country of origin, the price or quantity on the market,
> and or the dealer/seller's origin have a bearing on the "validity" of a specimen?
As with everything criminal it comes down to a motive. Most of the time it will be financial, but not always, the great Kingsbury frauds in the UK last century were not financially motivated at all, the best we can guess is that he was after respect, either that or he just enjoyed the fact that he was deceiving so many people. But for financial motivations then yes, it's going to be higher value specimens that are affected primarily. Everyone has been caught out by frauds in the past - collectors, dealers, it's not just a matter of only buying from "honest" dealers or not, because we all make mistakes. I've bought things that have proven to be fake even though I've examined them and convinced myself they were genuine. Dealers who deal with hundreds of new specimens a day really shouldn't be blamed when something slips past them.
Lyla J. Tracy April 26, 2010 09:39PMHi Jolyon, thanks for your opinion.
In my opinion, these beautiful Madan galenas, if proven to be fake, would require a high degree of skill to construct. However, where money is involved and time is cheap, anything can happen.
Off topic here, through the years I have seen my share of faked gold specimens, and am typically quite skeptical at first glance. Last year I deliberately purchased a fake gold specimen so I could take it apart and prove that it was manufactured....as shown here on mindat. Unfortunately the manufacturer is still in business, and likely still selling his "wares", though I haven't heard of them showing up at any more major shows.
Rob Woodside April 27, 2010 08:18PMThere are natural hoppered and dendritic galenas. There are also skeletal galena cubes with abrasion impacts visible at 10 power. Without photomicrographs how do you know what respected mineralogists are looking at and making pronouncements about??? So a great mineralogist pronounces them real. Does that mean the ones people have made are real? Let's get real with some photos, surely the visible abrasion impacts will sort this out!!!
Alfredo Petrov April 28, 2010 01:02AMMe neither, Rob. I don't attach much weight to the pronouncements of experts unless accompanied by the reasons which lead them to their conclusion, which so far no one has presented. This level of discussion is more appropriate in the field of theology.... "My authority is more respected than your authority", with no proof presented by either side.
This may be one of the longest threads ever on Mindat, but on reviewing it I find little reason for it to be this long, considering the paucity of hard data presented - just lots of opinions, and irrelevant comparisons to photos of galenas with hopper-faced crystal growths. Things I'd like to see are: photos of the minerals in situ, photos of the minerals being worked out, close ups before cleaning, SEM photos of the interior surfaces, analyses of the white powder residue inside the cavities, etc, etc. In the meantime, I'll just consider them "suspicious, but not proven either way".
Andrew Tuma April 28, 2010 09:27AMAlfredo, I am so sorry that I have with my recent post and photos, I extended this thread to a point that has caused you so much pain. However I thought that a photo of the galena that was hollow that and had another solid crystal sitting over the hollow section would be of interest, without doubt this was not the case and you have treated it with a level of indifference because your mind appears to be made up - they are all fakes unless proven otherwise.
So can I take it that without a expert opinion and/or a respected authority's blessing, you must doubt all specimens and their locations. If this is the case you then must doubt the Stolzites from Tasmania because there are no photos of them insitu, or being removed, no respected authority noted their occurrence insitu, (Ralph may have but not told me), the area where they were found has been removed by mining. I am sorry but I can not provide you with any of the information you have asked for, so you and all other people will have to accept the locality information that was provided to the mineral world by a bunch of amateurs.
Sometimes one must take a "leap of faith" because solid evidence of proof is not available, otherwise we may miss the pleasure and enjoyment of something that can not be explained.
And my opinion is...my piece is naturally formed.
Jolyon & Katya Ralph April 28, 2010 10:13AMWe are right to be suspicious and to discuss things.
Remember what happened with the Himmelsfurst silver specimens? One major journal did its very best to cover up the whole thing in order to protect its advertisers, and a similar thing happened with the yellow 'Tajik' Beryl
I have had some of my main advertisers talk to me about these skeletal galenas, obviously desperate that this problem will disappear - I cannot say any of them have given me pressure to remove things because it certainly wasn't like that, but it was clear that they are unhappy. I dislike them being unhappy, and I wish there was a quick and easy answer to prove one way or the other, but I'm not going to stifle a debate because of commercial interests, even those affecting mindat directly. Thankfully all the dealers involved understand my issue entirely (and they also, like me, want to know the truth).
ps. If anyone does want to buy one now is probably the best time - with the uncertainty the dealers can't price them as high as they probably are worth. But it's a gamble, if they're proven genuine, value will skyrocket for sure.
Alfredo Petrov April 28, 2010 10:56AMAndrew, your posts have caused me no pain, and I do find the photos of weird galenas to be interesting and informative, and I certainly do enjoy looking at them. I just don't believe they solve the mystery of the disputed galena crystals, because they show mostly depositional (growth) features rather than etch features. And my mind isn't made up, I clearly stated that I consider them suspicious but not proven either way, fake or natural. And that does not mean I have to doubt all specimens and all localities, only the suspicious-looking ones, which is just common sense. Most minerals don't look suspicious at all, and on other posts on this forum I have stated I believed specimens to be natural that other collectors were suspicious about. So it works both ways. And, as Jolyon pointed out, we are right to be suspicious and discuss things. Without suspicion, there would be no discussion, and without discussion no learning.
Robert Simonoff May 04, 2010 01:21PMThis discussion is getting more and more interesting. So now I am wondering what would constitute proof that these are natural
One could look for indications of mechanical means of material removal through an SEM. However, this approach was discredited as proof, since an acid bath afterward could act to hide these patterns. Nature could have also provided an acid bath, so presence of etching via acid doesn’t seem to prove anything.
There have been thoughts of looking for acid etch patterns in order to determine if acid was "painted" on the faces to get these patterns. Again, nature could have provided acid, so evidence of acid etching wouldn't prove anything.
If tests could determine that acid had indeed been present ONLY on the etched portions of the crystal and not the outsides of the same crystal, that would be suspicious I assume.
John Rakovan did a wonderful talk at the Rochester Symposium on determining if gold crystals were real or faked. He used xrays on some pieces and determined them to be faked because the resulting pattern showed multiple crystals (polycrystalline) instead of a single crystal. He realized however, that xrays on gold could not penetrate very deep, so he did a deeper scan using neutrons (at a military collider). The deeper scan conclusively showed the pieces to be a single crystal. The multiple crystal effect was only a surface effect – probably caused during a beating, as would happen if it tumbled down a river or stream For more information, look at the article in Rocks & Minerals (January/February 2009). I wonder if microabrasion would cause the same effect. Since galena is also malleable, maybe the same tests could be used. Unfortunately, I think John’s opportunity to use a military neutron collider was a once in a lifetime experience.
So is there anything we could look at to be conclusive about this from the acid/mechanical perspective?
Another idea has been proposed by Jolyon in an earlier post. This idea is that as the crystals formed, the solution changed composition. This change afforded something (a different metal ion? other impurities?) that were incorporated in the crystal structure that made the outer portions of the crystal more stable than the inner portions. If these crystals were forming as hoppered, maybe, just maybe you could get these patterns. If this were the route, possibly a microprobe analysis of the features could tell us if the composition were slightly different? I am not sure that microprobe would tell the whole story though ... do we know enough about how galena dissolves in different solutions and the rate of dissolution to be able to do a useful analysis?
Another thought had been offered relating to other minerals involved in the specimen. Quarts growing through the holes, for example. We could remove the quartz and look for glue. If the quartz goes through the holes in the galena AND it is not glued in place, does that help prove anything? There are also pieces that seem to have some kaolinite on the galena. So how is that attached and how did it get there? Maybe that would afford us something to research.
Another "proof" would be photos of the pieces in sito. However, it seems to me that this is the easiest falsify. Photoshop or staging of the already prepared pieces in a mine would be the counter claim.
So what tests could be used to prove or disprove that these were made by nature. It has been said many times that what nature can do to these pieces, man can do as well. So is there any conclusive tests short of shipping a bunch of mineralogists to Bulgaria to study them in suto - and pay them enough so they could be bought by unscrupulous miners?
Edited 2 time(s). Last edit at 05/05/2010 12:27AM by Jessica and Robert Simonoff.
Robert Simonoff May 04, 2010 08:23PMI don't have any pieces yet, but I have access to some if we can come up with some tests worth doing on them. I could do a microscopic examination and post pictures. Certainly is there are the indentations that would be indicative, but lack of spherical indentations would prove nothing right?
Rob Woodside May 04, 2010 09:00PMThe stepped CLEAVAGES and not dissolution features was what I was looking for in Tucson. The spherical abrasion impacts were just icing on the cake. I didn't realize that Galena was that malleable to leave them!!! Pictures of the sharp cleavage steps should be sufficient to debunk these. So please make some photomicrographs, then others can judge.
Knut Eldjarn May 05, 2010 07:37AMI have like Alfredo been very open-minded as to the authenticity of the reverse skeletal galenas from Bulgaria. But since this thread has been public of Mindat for nearly half a year now - with NO evidence of their natural origin forthcoming, I am becoming more sceptical. Specimens seem to be trickling out, so it was probaboly not a stash from a log-time-ago find. Therefore I am sure that there are people out there who know the answer to the question and they are probably also aware of this discussion. It should have been in their interest to present some additional information -i.e. pictures of the specimens in situ or at least before cleaning etc. Such "proof" may of course also be faked, buit as long as there seems to be a complete silence along the chain of supply for these specimens, I have become very sceptical about their origin.
Robert Simonoff May 05, 2010 08:12PMI think I have been able to confirm that I have access to specimens and a mineraligy lab in which to do tests. The only tests I have seen mentioned that could be performed are microscopic and possibly SEM examination. And if I am understanding correctly, these wouldn't convince people of anything.
So all I can do is get magnified pictures which may prove it is fake,
Rock Currier May 07, 2010 10:41AMThe best way way to convince yourself that these are most likely fakes is to find some little natural cubic galena crystals on or off of matrix, or even a cubic cleavage of galena or both, get access to a micro abrasive tool, load it up with glass beads and go to work on the thing and see how easy or difficult it is to create these. Then you won't have to rely on what other people tell you. This is not rocket science. If you don't have a microabrasive tool, find one you can borrow time on. Most museums or universities with Paleo departments, fossil dealers and many serious mineral dealers have these machines. If you are in the Los Angeles area, Ill even let you use one of mine.
Crystals not pistols.
Alfredo Petrov May 08, 2010 06:08AMYes, I've seen those too, but unfortunately they don't prove the issue either way, because the quartz predates the galena. I.e. the quartz was an inclusion in the (younger) galena, and the quartz xl is exposed in the cavity when the cavity formed. Being much harder than the galena, and chemically more resistant, it is left standing in the cavity either way, whether mechanically abraded or naturally chemically etched. Now if you could find a calcite xl standing in the cavity, that would indeed prove natural origin.
Jolyon & Katya Ralph May 08, 2010 11:53AMI think it's interesting that there hasn't been a stronger defence of these specimens - if I had been finding these and trying to sell them I would be very upset with these allegations that they are faked and I'd want to make sure I could prove to everyone that they were natural, and go out of my way to do so.
The response has been somewhat muted, to say the least. I still hope they are natural, but without proof they are still far to suspicious to accept in my opinion.
It's an interesting debate because there are several people who's opinions I trust very much (including mindat managers) who are convinced they are genuine. And several others who thing exactly the opposite. I'm really looking forward to a conclusion to this.
Robert Simonoff May 08, 2010 02:22PMWell, we are willing to give it a go. We have access to specimens for sale. Some of quartz inside, some have kaolinite. We have some labs that are willing to help out with equipment (SEM, single crystal XRD) and we have a rock scope. We am not going into this with an assumption one way or the other.
The plan is to ask mindatters for samples they have made. Make your best ones. Send us a PM and we will send our address. We will return them unharmed once the experiment is done. We will ask permission from the owner before doing any destructive tests. Also, please send a brief description of how you made them.
Then we will get the samples from the dealer who is donating some to this cause.
We will start with visual and loupe inspections to make observations and take photos.
Then we will use a scope and take pictures of each in order to determine if it is trivial to tell the difference between the known manmade specimens and the unknowns.
If necessary we will go down to the SEM level to try to see differences. We may also try to do some microprobe work to see if there is anything interesting about the composition of the galenas.
Finally, based on work that John Rakovan did, we will try to see if the galena crystals too a beating on their interior surfaces using the single crystal XRD machine (Rigaku). Based on the work he did with gold, we may be able to tell if these were exposed to repeated impacts from abrasion.
If people have thoughts on what else should be done, I'd love to hear it. If people have specs they'd like to donate to this experiment (as per the above) PM us.
We understand this will not convince everyone, nothing will. We also understand there is no way to prove these are natural - that point has been made abundantly clear. But, maybe, if the pieces that are known to be manmade means can be easily distinguished from the other specimens, the debate will be reset somewhat. Ideally we would have a team of mineralogists who are so rich they couldn't be bought off and who have no families that could be threatened by unscrupulous gangster miners, see them in situ. But lacking that, this is the only idea we have come up with.
As we get pictures and information mindat will be where we post everything. Would an article would be the best vehicle? There will be LOTs of pictures if we can get this experiment off the ground (which depends largely on obtaining a variety of known manmade specimens).
Note: We do not have permission to use a Rigaku or similar device yet, we am working on that. We do have permission to take advantage of an SEM, however.
Edited 1 time(s). Last edit at 05/08/2010 04:25PM by Jessica and Robert Simonoff.
Knut Eldjarn May 08, 2010 06:18PMBob,
you mention having access to specimens with "kaolinite" inside. A SEM-picture of such material from the cavities would be highly interesting. They might turn out to be a natural clay mineral - or possibly remnants of an abrasive material... ?
Robert Simonoff May 10, 2010 03:32AMRock, could you please post closeup pictures?
Rock Currier Wrote:
> I was one of several people that were instantly
> suspicious of these cavernous galenas when I first
> saw them. As soon as I got the chance I made one
> on a small air abrasive unit I had. They are
> simple to make if you have a small air abrasive
> tool and a galena cube. Use glass beads and about
> 80 psi air and in about ten or 15 minutes you can
> make one of your own. Other friends of mine also
> were able to duplicate these types of specimens.
> One made a very attractive one using octahedral
> galena from Sweetwater, Missouri. Another, only as
> a lark, using carborundum grit made a nice one out
> of fluorite. I suspect that we will see these
> coming to market soon from eastern Europe as soon
> as the idea occurs to them. Use diamond powder and
> I suspect you could make them out of spinel
> octahedrons if you wished. There are a lot of
> possibilities. But like the new spectacular wire
> silvers from Germany, it is not easy to prove that
> they are definitely fakes. I for myself, would not
> want one in my collection except as a joke to show
> friends. For specimens like this shown on Mindat,
> at the very least there should be inserted a
> comment that some knowledgeable people suggest
> that you take into consideration that they might
> be fakes at least until such time that they can
> definitely be proved to be natural.
Harris Mason May 10, 2010 05:37PMHello everyone,
As just a casual observer of this discussion I have been pretty interested in the discussion taking place. In my own research I have made in my lab completely hollow mm sized pyromorphite crystals and it is possible to make the same with chlorapatite as well. But that is a different system with different issues. Mainly I saw Jolyon post "ps. If anyone does want to buy one now is probably the best time - with the uncertainty the dealers can't price them as high as they probably are worth. But it's a gamble, if they're proven genuine, value will skyrocket for sure. " So I said heck I will search for some on google and stumbled across a paper on Madan Galenas with fluid inclusions from 1977.
I.K. Bonev Mineral Deposita (Berl.) 12, 64 - 76 (1977)
In it they have detailed SEM investigation of the surfaces of galenas where reverse crystal impressions are observed forming from fluid inclusions. They state these can be casually observed by the unaided eye. These could be the "abrasion pits" mentioned in earlier posts.There is also description of the parallel lined curved surface sculpture. I am not taking a side on this. I have no vested interest in one way or the other. Just a mineralogical curiosity for me. I do however think this paper could aid significantly in this discussion since they have a detailed study of how these reverse crystal structures form.
Mike Keim May 13, 2010 03:33AMHere are pictures of my example from this find. In the first picture you can see bits of chalcopyrite along some ridges and other mineralization along an inner ridge. This could only occur by either A) being artfully placed there after sandblasting (but why, and I see no evidence of glue), B. grew there naturally after natural skeletal growth of the galena, or C) the minerals were included within the Galena and exposed after sandblasting. I think the best answer is B, the minerals are on different "contour lines" of the Galena and would have had to be random inclusions within the Galena, which I think is unlikely.
The second photo shows small pyrite lined vugs exposed within the Galena - if the crystal was sandblasted, those vugs would also show abrasion, and they do not.
Last photo shows some quartz crystals. They do not show abrasion, but sandblasting could have been done by softer material than Quartz. For reference, Galena is 3cm across in size.
open | download - g5.jpg (66.2 KB)
open | download - g6.jpg (65.3 KB)
open | download - g7.jpg (54.1 KB)
open | download - g6.jpg (65.3 KB)
open | download - g7.jpg (54.1 KB)
Knut Eldjarn May 13, 2010 06:38AMMike,
thanks for posting the pictures. Based on those the specimens could be natural - or manmade. Pyrite is so much harder than galena so one could imagine that a softer abrasive would not affect those. One might also ask why a natural process creating the dissolution patterns in the galena did not affect the pyrites...
Alfredo Petrov May 13, 2010 07:03AMThanks for the clear photos!
Air abrasive units commonly use microscopic glass beads (hardness 5), looks like powder to the unaided eye, not quartz sand, so "sandblasting" is a bit misleading. Glass microbeads do not abrade pyrite or quartz. The photos show what one would expect if air abrasive had been used: galena deeply eroded; chalcopyrite abraded but slightly protruding from the galena surface because it's a bit harder than the galena; pyrite and quartz unaffected. This is not to say that your piece was made that way, Mike, merely that it could have been done that way.
Jolyon & Katya Ralph May 13, 2010 11:48AMVery interesting photos!
On the one hand, photo G2 is very interesting, it seems to show two depressions on one surface of the crystal and one on the other. Any previous theories that I could just about accept about how these could have formed are somewhat blown out of the water by this, And it looks sculpted, it very much looks air-abraded.
Photo G7 shows a very sharp edge to the depression in the top left corner, not a rounded blob depression as you see in other photos, I find it much harder to see how this particular depression could have been made by an air-abrader.
I love the fact these are so confusing. Perhaps there are some natural depressions in these crystals and they have been "improved" with an air-abrader to make them more valuable?
Joseph Polityka May 13, 2010 03:28PMHi,
My two cents worth: they might be real, and if they are, they are not worth the high prices being asked. These are not cavernous gold crystals, are they? Contemporary specimens of galena are galena, period. If they were high quality specimens from a defunct, classic locality then the price would be no object.
I would be interested in hearing from the miner or person that was closest to the source when the specimens were found. Who are those people?
By the way, I hope they are genuine.
Alfredo Petrov May 13, 2010 05:29PMYes, if you look at polished ore sections, you more often than not see complex networks of inclusions. Metallic inclusions at different depths in other metallic minerals are just as common as nonmetallic minerals included in quartz, etc. Not a surprise; you just don't see them normally because of the opacity.
Donald Slater May 13, 2010 05:53PMThis is getting interesting. There seems to be a few more people on the man-enhanced side that the real though. I tend to believe they are man-enhanced over all but could it be possible that there were some natural crystal at one time but because of the high prices some creative soul decided "I can make these". Money does bring out the creative process. The ones that seem the most likely to be fakes are the ones that are etched all the way through. I just can't imagine a natural process that could leave the outside almost untouched and eat all the way through. Ones that are more of an indentation remind me of a hopper growth and have then under gone some sort of natural etching. I am leery of that but it is and idea. The main point of suspicion for me is that they have not been seen insitu and their origin seems to be vague. Oh well more fuel to the fire.
Anonymous User May 14, 2010 01:54PMVery interesting thread.
I don't have any dog in this fight - I neither collect nor sell any kind of galena.
However, as one who used to operate a glass bead blaster in a small factory, I believe that it is somewhat misleading to simply state that glass beads have a hardness of 5, and therefore would not abrade anything with a hardness over that number. Because of the velocity of the beads, there is wiggle room. This is just based on my feeling from my limited experience with the equipment. I believe a similar effect is used in lapidary when an abrasive powder that is softer than the stone being cut is used for the final polish. In this case, I believe it is the pressure on the lap that allows softer powder to abrade. Anyone agree or disagree?
I'd like to see someone test the bead blaster on some of the associated minerals - to see if they are indeed untouched when the rate and time required to abrade the holes in the galena is applied.
Anonymous User May 14, 2010 02:54PMCertainly without touching quartz - but without touching pyrite or especially chalcopyrite? I'm picturing the product, pressure, volume, and time required to significantly abrade galena. I'm just wondering if this operation would affect the associated minerals. I don't think it's a simple as saying "the abrasive medium is softer than mineral X, so it won't be abraded."
I've never seen any of these specimens in person. I'm highly skeptical that they are natural. I'm just pointing out that further investigation into the effects of abrasion on associated minerals may be warranted.
Rock Currier May 14, 2010 09:42PMCertainly there is plenty of "wiggle" room for glass beads to effect and abrade harder materials. A lot depends on the velocity with the glass beads impact the surface of the material. Although glass beads at about 60 psi entrained in an gas stream will usually not produce any visible change to Quartz, it will have some effect on the Quartz. After subjecting the quartz to glass beads at 60 psi. and placing the quartz in HF for a while, it is evident that the bead blasted surface will etch much more quickly than the unblasted surfaces. Glass beads at 60 psi will also not produce visible effects on the surfaces of shiny pyrite crystals but will eat up similar chalcopyrite crystals very quickly. Glass beads are commonly used to remove chalcopyrite from around Russian Sperrylite crystals. Also frequently the glass beads used to clean minerals are used many times over and often contains quartz fragments and fragments of other minerals that were removed from other minerals cleaned previously. This kind of "impure" glass beads can abrade quartz and tourmaline etc if you are not careful.
High pressure water is a very effective cutting media for concrete and granite. Diamond photographic needles are certainly worn away by soft plastic records over time. There is a lot about "hardness" that is not well known.
Crystals not pistols.
Alfredo Petrov May 15, 2010 05:22AMNo one claimed that the chalcopyrite was not affected by glass beads, it would certainly be abraded, but less rapidly than the surrounding galena, which leaves the chalcopyrite standing out a bit. Yes, the surfaces of hard minerals can be damaged by percussion of softer objects (Yes, you can knock flakes of flint off with a piece of bone too), so it is up to the operator to choose a pressure and medium which will remove the undesired material and keep the desired material undamaged - easy enough when the hardness difference is as striking as galena and quartz.
Don't forget that these tools are more frequently used by fossil preparers than by mineral folk, and the fossil people are working on tiny details and materials of much smaller hardness difference - It is by no means the brutal clumsy tool that some of us seem to think.
But Rock's comment about etching after blasting brings up an interesting potential experimental procedure: Check the relative speed of etching (with ammonium bifluoride?) of a quartz crystal from inside a galena cavity with a (presumably unabraded) quartz from outside a galena cavity, on the same specimen. If sufficient blasting pressure had been used, one would expect the quartz from inside a cavity to get more etched. (Might not be definitive though if blasted at low enough pressure?)
Peter Haas May 15, 2010 08:20AMThis is NOT skeletal growth. Alfredo pointed this out earlier. Skeletal growth, like normal growth, starts from a nucleus and proceeds in all three dimensions (although the rate of growth may be different in each dimension, depending on the mineral studied and anisotropy effects of the medium in which they grow). Skeletela growth of galena is well known, but produces entirely different shapes. There is an article on the web showing this:
What we see here are forms with a missing core. Name them as you like ("frames" seems to be appropriate), but don't call them skeletal. If they were grown like this, where did it start ? Irrespective of where the nuclei were initially located, a convincing mechanism needs to be found that alters the growth rate along the two directions of the three spatial axes. Otherwise, the growth would not have stopped at the corners !
The only way they could have formed naturally is by an etching mechanism.
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