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Fakes & FraudsFake pyrite concretion?
12th Dec 2010 13:49 UTCReiner Mielke Expert
12th Dec 2010 15:30 UTCIan Jones Expert
12th Dec 2010 15:30 UTCDennis Tryon
12th Dec 2010 15:32 UTCDana Slaughter 🌟 Expert
I've examined these at the 2010 Tucson Show and they appear completely legitimate to me. I saw several examples that were of poor quality and doubt that one would take the time to manufacture ho-hum specimens. Several major US dealers had examples and I haven't heard of any suspicious commentary. Still, with the increasing propensity to enhance or manufacture specimens one really has to be on alert.
Happy Holidays!
Dana
12th Dec 2010 15:39 UTCAlbert Mura
12th Dec 2010 16:15 UTCReiner Mielke Expert
12th Dec 2010 16:17 UTCSteve Hardinger 🌟 Expert
12th Dec 2010 16:27 UTCAlbert Mura
12th Dec 2010 16:49 UTCReiner Mielke Expert
12th Dec 2010 16:59 UTCAlbert Mura
12th Dec 2010 17:10 UTCReiner Mielke Expert
12th Dec 2010 17:15 UTCAlbert Mura
12th Dec 2010 17:27 UTCReiner Mielke Expert
12th Dec 2010 17:30 UTCReiner Mielke Expert
Not knowing what the matrix is but if it were calcareous you could also accomplish this with acid.
12th Dec 2010 17:34 UTCAlbert Mura
12th Dec 2010 17:42 UTCJolyon Ralph Founder
No idea whether it's natural or faked. But some of the suggestions being made here are plainly wrong.
12th Dec 2010 17:53 UTCReiner Mielke Expert
12th Dec 2010 18:02 UTCReiner Mielke Expert
12th Dec 2010 18:32 UTCAdam Kelly
There are too many, too cheap for me to believe they are fabricated.
I have worked as a jeweler for about fourteen years, and details are my work.
I saw absolutly no "refinishing" anywhere on any of these.
Adam K
12th Dec 2010 18:34 UTCRock Currier Expert
12th Dec 2010 18:35 UTCReiner Mielke Expert
Don't give them any ideas!
12th Dec 2010 18:37 UTCAdam Kelly
shapes than balls and egg shapes would cause a variety of other shapes to show up on the market."
Great point Rock, If they were making them where are the hearts and stars.
12th Dec 2010 18:37 UTCReiner Mielke Expert
12th Dec 2010 18:52 UTCAlbert Mura
12th Dec 2010 18:54 UTCAdam Kelly
Just a different soup.
Pyrite link... http://www.mindat.org/photo-185225.html
Azurite link...http://www.mindat.org/photo-225846.html
12th Dec 2010 19:01 UTCHoward Messing
http://www.messingminerals.com/spec_detail.php?id=754
http://www.messingminerals.com/spec_detail.php?id=755
http://www.messingminerals.com/spec_detail.php?id=756
http://www.messingminerals.com/spec_detail.php?id=571
http://www.messingminerals.com/spec_detail.php?id=1729
and something similar from New York State:
http://www.messingminerals.com/spec_detail.php?id=1837
I was curious if they were real myself but was reassured by 3 separate well known dealers that they were. Of course that doesn't prove anything. In any case my wife really liked them and said she doesn't care if they are real or not. She has them displayed on our coffee table in a pretty "sculptural" arrangement that we enjoy.
I would certainly like to know how they are formed, either naturally or not, as everyone who sees them asks.
12th Dec 2010 19:49 UTCReiner Mielke Expert
12th Dec 2010 19:58 UTCAlbert Mura
12th Dec 2010 20:24 UTCReiner Mielke Expert
12th Dec 2010 20:56 UTCColin Robinson
12th Dec 2010 21:21 UTCAlbert Mura
12th Dec 2010 22:15 UTCReiner Mielke Expert
13th Dec 2010 02:14 UTCMatt Neuzil Expert
onto how they are formed its interesting but i also believe there is enhancement as you can see in the matrix phot they dont look very appealing to me.
13th Dec 2010 03:14 UTCDana Slaughter 🌟 Expert
I personally like the specimens and would be thrilled to happen upon a shale layer loaded with the buggers!
Dana
13th Dec 2010 10:09 UTCJolyon Ralph Founder
you simply can't state things like that as fact without evidence. You should learn to use words such as "I believe" or "probably" in your replies.
13th Dec 2010 12:04 UTCJohn Krygier
http://www.mindat.org/gphotos/0263888001131752633.jpg
I have one that is more spherical than the one above, and with smaller pyrite crystals in bands around the concretion similar to the Chinese examples. It was allegedly found in one of the ravines around here. I need to ask the guy who gave it to me where, specifically, he found it.
I've posted my hamburger pyrite before, which I plucked from a ravine in Columbus:
http://www.mindat.org/gphotos/0345602001277642514.jpg
Concretions in general are bizarre, and if you do a google image search you will find some really strange items prone to all sorts of conspiracy theories.
My sedimentary geology colleague told me that in general concretions are seen as a curiosity by geologists, and are not much studied. There is a general understanding of how they form but many specific forms are not well studied. I did a quick search on China Shale Concretions in the scholarly lit and there is some material there, just no immediate proof (images, etc.) that the Chinese pyrite concretions are natural and unaltered.
John K.
13th Dec 2010 16:54 UTCMichael Hatskel
I have never held one in my hands and all I know about them is what I see in the photos. So I am not stating anything here and not questioning if they are real or fake. I would still want to understand how such thing could have formed.
What I am questioning is if they should be called pyrite concretions. I don't think they are, because pyrite only makes thin parallel bands in the shale (btw, is it really a shale?). So, we have the rounded chunks of shale (with pyrite in them) sitting in the same shale? Or the matrix is a different rock?
Pyrite concretions in sedimentary rocks represent the accumulations of recrystallized pyrite that was mobilized from inside of the host rock. I don't see that mechanism at work here, because pyrite is not massive.
Also, the accumulations form where some space is available or as a replacement. Could those ball formations be some sort of a replacement? If yes, what could that be that those balls have replaced?
Large balls are well known from the residual bauxite deposits, but those grow from inside, just as the pyrite or other true concretions do. Those gibbsite balls are essentially the giant pisolites, that's how they get so well rounded. Again, I don't see that mechanism at work here.
What I see in the photos is the rounded chunks of a sedimentary rock with parallel pyrite bands (not unusual at all) incorporated in the newly formed clastic sediment.
Question to those who know what kind of black rock is the ball and the matrix: Could that kind of rock be rounded so smoothly or it would simply not survive the prolonged natural abrasion needed to become a ball?
And the last question: have anyone seen the ball's cross section?
13th Dec 2010 19:11 UTCIan Jones Expert
have you actually seen or handled these?
They may perhaps turn out to be fakes, but to me, they certainly don't look like it. There is no abrasion on them, they are plentiful and they are in a wide range of sizes. And regardless of that, they are all uniform in shape and habit. There certainly doesn't appear to be any artistic interpretation here.
14th Dec 2010 00:59 UTCAlbert Mura
14th Dec 2010 02:10 UTCReiner Mielke Expert
Is that better Jolyon?
14th Dec 2010 02:51 UTCJolyon Ralph Founder
The natural world continues to throw amazingly odd things at us, and it would be totally wrong for us to discount such things out of hand.
14th Dec 2010 02:52 UTCAlfredo Petrov Manager
Asians do tend to like to give matrix an artistically sculptured appearance - as for example with the chipping of the white marble matrix of the pink Vietnam spinels. I don't particularly appreciate that technique myself, but we mineralogically scientific Westerners are only a small segment of the market for such stuff, so we can avoid buying them, but that's not going to have much influence on the custom.
14th Dec 2010 17:45 UTCDavid Von Bargen Manager
14th Dec 2010 18:50 UTCDean Allum Expert
If you bury these in an organic rich, reducing environment for a million years, the chemical reaction produces pyrite, just as it does for the pyrite "dollars" found in the midwest U.S. coal mines.
-Dean Allum
14th Dec 2010 19:00 UTCRobert Knox
Because this type of nodule is formed in sedimentary deposits, the banding could be explained by the differences in the makeup of the individual layers of the sediments.
I have in my collection a "spherical" pyrite in black shale matrix from China, that is entirely made up of cubic crystals. Sorry no photos, but it is 3cm big(the nodule) with the individual crystal face of 2mm.
Bob
15th Dec 2010 00:48 UTCReiner Mielke Expert
15th Dec 2010 04:40 UTCFranz Bernhard Expert
15th Dec 2010 08:33 UTCRoger Lang Manager
IMHO they are all natural .. i have had some of those in my hands and i have seen a picture of them in situ in a mudstone/shale (but do not remeber who showed me the picture). To me they are nothing unusual re formation ...
There are single "balls" as well as "bread leafs" and double "eggs" etc.
Cheers
Roger
16th Dec 2010 04:13 UTCJim Bean 🌟
16th Dec 2010 22:19 UTCGeorg Graf
for me these Pyrite concretions are natural.
I imagine, the Pyrite grow in mud at the borderline of two stata of fluid with different O2 content, Fe content ore other chemical/physical conditions. And this borderline sink and go up by the time; maybe with the rainfall, summer heat ore other climatic conditions.
My wife comes from Shanghai. Since I met her, I say (, if she can not hear it): "If You have to do with Chinese, think like Chinese." - But in this case, I think, the P. concretions are natural.
And an other important point, which has nothing to do with mineral collecting: If China is econmically developed like the Western World, the economy of the Western World will not break down! Like the British economy broke not down at the end of the 19th century, when Germany and Austria became technical and economical developed like England!
Inhonest dealers You find all over the world. - There are many fakes of and fraudulent Trilobites from Morocco. The Morocco people learnt it from white dealers, how the make a trilobite fake!
Greetings from Thale near Goslar
Georg
21st Mar 2012 13:40 UTCEric Greene
21st Mar 2012 22:38 UTCPhil Richardson
Unfortunately, my initial observations is that some are going to be problematic. A little over two and a half years ago Mike New, of Top Gem in Tucson, imported thousands of Chinese pyrite concretions. Solid pyrite concretions, with no shale banding, and the appearance of crystalized surfaces. (Top Gem had been importing them for a number of years prior to this, but not anything like this shipment for quantity.) The bulk of the pyrite concretions that I chose from were round, with a sizable percentage flattened discoid shaped. I was careful, sorting through hundreds, and picked out ones with minimal flaws, and specifically no cracks.
Now several years later a number are starting to have issues. Out of 12 flattened discs, ranging in diameter from 4cm up to 6.5cm, 5 now have radial cracks with one severely cracked. All of the spherical pyrite concretions that I picked out, under 5cm in diameter and showing prominent crystal faces surrounding the exterior surface, are fine. They show no cracks, discoloration, nor do they 'smell'. Now I cant say the same thing for the large ones that I chose. I picked out several exceeding 10 cm in diameter. Out of three, two are starting to turn. They are developing a darker patina, and have several areas with lighter discoloration appearing. Picking them up, and smelling them, they are developing a noticable odor. I have removed the big ones from display and storage with other pyrites. What I did notice, is that the larger diameter pyrite concretions have smaller crystal faces showing on the surface, and more resemble 'scales' instead of cubic faces.
Upon close inspection, with a hand lenses, I can find remnents of shale matrix down in crevices between crystal faces on most of the Chinese pyrite concretions. It has only been recently, in the last two years, that I started noticing the shale banded pyrite concretions. I did pick up two feeling that they were legitimate natural specimens, similar in occurence to those I already had. I have not yet had any issue with those.
Sorting through so many pyrite concretions, I was fortunate to see several which had been broken in half. The interior showed bright 'pyrite' colored material with a fibrous radial pattern. It was similar in appearance to the interior sections that I have seen in French marcasite concretions. I am not sure if that type of structure has any relevance, since crystalized pyrite, when broken, has a semi-concoidal fracture.
Phil
22nd Mar 2012 07:25 UTCBen Grguric Expert
It is quite common in many of the occurrences of these spherical or spheroidal pyrite concretions that the internal structure includes zones which are pyrite intergrown with some marcasite. Examples I've looked at under the reflected light microscope were from Dover, England and several places in the Goldfields and Pilbara province in Western Australia. This marcasite component is quite distinctive in reflected light and I suspect this mineral is the main culprit responsible for the concretions falling apart in a damp atmosphere.
Cheers,
Ben.
11th Apr 2012 20:47 UTCRobert Knox
31st May 2012 17:15 UTCTim Jokela Jr
Now I really want one of these things, to put to the saw.
1st Jun 2012 22:15 UTCJohn Krygier
This thread has been going on so long that an entire research project on similar iron-sulfide shale concretions in central Ohio has been completed (since I last posted) by an undergraduate student in our department. The project was presented at a GSA meeting a month or so back, and the abstract is below. The link goes to a GSA page with a big PDF download with information and data for the geologically inclined. The research focused on the stages of development of the concretions, their organic origins, and their mineral composition (pyrite and marcasite - which develop in a complicated manner - see the PDF at the GSA link below). Eric's plans to continue studying the geomicrobiology of the concretions in graduate school. I'm not a geologist (I work with them) but this was a fun project to follow.
Marcasite and pyrite in the concretions (reflected light microscopy (RLM)):
http://makingmaps.owu.edu/minerals/pyrite-marcasite-ohioshaleconcretions.png
Some SEM images from one of the concretions:
http://makingmaps.owu.edu/minerals/sem-ohioshaleconcretions.png
Below is an image of one of the flatter concretions cut in half. A spherical specimen was cut, but I don't have a picture at the moment.
http://makingmaps.owu.edu/minerals/pyrite_toad_cut_all1.jpg
GSA Abstract & PDF download: http://gsa.confex.com/gsa/2012NC/finalprogram/abstract_202972.htm
IRON-SULFIDE CONCRETIONS OF THE OHIO SHALE: GLIMPSES OF DEEP SUBSEAFLOOR MICROBIAL ECOSYSTEMS OF THE LATE DEVONIAN
MUMPER, Eric, Department of Geology and Geography, Ohio Wesleyan University, Delaware, OH 43015, mumperman@gmail.com and FRYER, Karen H., Department of Geology and Geography, Ohio Wesleyan University, Department of Geology and Geography, Ohio Wesleyan University, Delaware, OH 43015
Recent interest in black Devonian shales for natural gas exploitation has brought shale research into new importance. At the same time, advances in the understanding of deep subseafloor microbial ecosystems have revealed that microbes play a more pivotal role in geologic processes than ever imagined. The convergence of these two areas provides an excellent opportunity to reexamine enigmatic concretions of the Ohio Shale. The Huron member of the Ohio Shale is distinguished by the presence of carbonate concretions. These concretions vary considerably in size and differ in composition from the host rock. Their origins have been questioned since they were first described in 1873. Current models attribute concretion formation to abiotic mineral replacement of organic substances. However, smaller, iron-sulfide concretions inhabit the same horizons and are less well studied. Iron-sulfide mineralization has been attributed to biotic processes and may be connected to the presence of the larger carbonate concretions. Iron-sulfide concretions have been collected from three sites in Delaware and Franklin Counties in Ohio. These samples were investigated using reflected light microscopy, scanning electron microscopy, and energy dispersive x-ray spectroscopy. Based on morphology, composition and size, the iron-sulfide concretions have been categorized into four different stages of paragenesis. These stages correlate well with known microbial zonations of deep subseafloor environments. Understanding the microbiological processes at work in the creation of black Devonian shales may shed light on how to exploit modern microbial systems to develop sustainable sources for carbon fuels in the future. GSA North-Central Section - 46th Annual Meeting (23–24 April 2012)
John K.
6th Jul 2012 01:25 UTCReiner Mielke Expert
21st Jul 2012 19:31 UTCHoward Messing
Ebay "Volleyball" from Kansas?
21st Jul 2012 21:00 UTCD Mike Reinke
22nd Jul 2012 00:53 UTCRock Currier Expert
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Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2024, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph.
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