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Cleaning Pyrite

Posted by Art  
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Art June 18, 2010 02:52AM
Hello everyone,

I was searching online and I found this thread of messages regarding someone asking "how to clean pyrite." I design jewelry in New York City, for a small company, and we have just finished production on necklaces using PYRITE beads. The goods have been shipped, but not on retail stores yet, and the customer, in dismay, reported that the beads left a blackish soot on her t-shirt. I had one of our employees wear it for a few hours, and she got it too. I need help, desperately.

I believe the pyrite beads are from China. What is this soot? If I clean the pyrite beads, will it still continue to happen? Does this mean the beads are just dirty, or have traces of acid, or is this a naturally-occurring substance.

I personally thank anyone who can help, even if just ideas. We are a small jewelry company in the garment district, and one of the very few who still manufacture in the US. This problem can potentially damage our business. I dont know how this blog/e-group works, but please email me too at art@veloira.com for your response.

Thank you VERY much,

Art
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Rock Currier June 18, 2010 07:41AM
Art,
First of all, are you sure your beads are of pyrite or perhaps rather marcasite? Often Chinese suppliers do not know for sure what it is that they are selling or will give it a name they think has more sex appeal. The chances are that they are pyrite because it is a very common mineral but it is something you should keep in mind especially dealing with Chinese suppliers. Pyrite is not the most stable mineral and will in time tarnish and loose its luster. Pyrite also has the bad habit of producing "black dust" when it rubs together. The black dust is just finely divided particles of pyrite that look black. It may be something as simple as the beads rubbing together that is creating the black dust. Do you have spacers between the beads that prevent them rubbing together? If not, the addition of spacers or big knots may cut down a lot on the "black dust".

Rock Currier
Crystals not pistols.
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Jolyon & Katya Ralph June 18, 2010 08:26AM
You might also need to protect the beads with some kind of varnish or similar coating to protect them.

Pyrite isn't one of the best materials to use in jewellery.

Jolyon
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Donald Slater June 18, 2010 03:24PM
Rock and Jolyon are right. Anyone who has ever cut pyrite knows what a mess it is. Everything turns black including your fingers. I cringe when I see people selling pyrite beads. Yes they look nice at first but it will tarnish and if they rub against anything hard or white will leave black. Rock suggestions of spacers or knotting in between will help to keep them from rubbing against each other but they will probably still leave black marks on any light color or white where they rub. I sell pyrite to people who set it in jewelery and I always advise them to make sure it is backed or wrapped so that it does not rub against clothes. It is amazing how abrasive cotton is. In another message string with someone on cleaning Galena it was pointed out that cotton can scratch it. Galena is softer but I was still amazed that it would be scratched by cotton. You might find some kind of lacquer that would keep it from leaving marks on clothes. The biggest problem with lacquers and varnish is they are easy to scratch not only by the beads rubbing against each other but also other jewelry in the jewelry box. Some lacquer yellows with time also. You might check with other jewelry makers and find a lacquer that is good for jewelry.
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Art June 19, 2010 01:29AM
Thank you for all the input! Very much appreciated.

I also read in an earlier thread, to use lime away to clean them? And also, "chinese powder?" (whatever this is :-). What are your thoughts on that idea?
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Rock Currier June 19, 2010 09:46PM
I have no idea what Chinese powder might be. Google gives several possibilities but I don't know how any of them might work on cleaning pyrite. Lime away is a commercial cleaning liquid that has among other things phosphoric acid it it. It does work to brighten up pyrite crystal specimens if they have not "weathered" too much. I don't have any idea on how it would work to clean up pyrite beads. Polishing pyrite is not a trivial job.

Rock Currier
Crystals not pistols.
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Anonymous User June 20, 2010 03:35PM
Hi there!

I believe the dust is pyrite powder resulted from the polishing.It could also result from rubbing to each other,but this may take more time to appear on a shirt,I think.As Rock and Jaylon suggested,leave spaces (with knots)between the beads and before putting them together give each bead an ultrasonic bath.

Let your clients know they shouldn't clean the necklace with water too often if they want to preserve it for longer without having the beads broken.


Hope that helps!
-Kostas.
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Pam March 07, 2012 02:16AM
Art - Read about your predicament. I, too, am a small jewelry manufacturer in Los Angeles and have been using a lot of pyrite in my jewelry. Am really concerned because I wanted to know how to clean pyrite and hence ended up reading your message. Sure wish the supplier I have been purchasing from had given me a heads up. Have you had any luck with any other info? I'll keep you posted on my end. Am going to find out if they can be coated....will let you know if I get any useful info. Already have about 30 necklaces fashioned from pyrite...they're beautiful but will they stay that way? Best, Pam
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Sherry Pollock June 06, 2012 04:52PM
Art - Thanks for posting this message. I tried researching this topic through the website of the supplier from whom I bought my pyrite beads, but didn't find any answers. For the record, I've had my beads since 2005, and they've been in their original poly baggie which was stored inside one of my plastic bead organizing boxes.

In the photo I attached of my beads, you can see that they have blackened over time. However, what I'm more concerned about is the crystallization present on some of the beads. I realize that it's likely oxidation resulting from the mineral's iron and sulfur chemical composition. Has anyone else experienced this? Do you think the Lime-Away would remove this as well without irreparably damaging the beads?

And Pam, if you figure out a way to coat the beads to prevent/cut-down on the tarnishing, I'd love to know too!!

Thanks again!
Sherry
open | download - Pyrite beads.JPG (411.9 KB)
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Peter Haas June 06, 2012 11:38PM
Sulfides in general don't like humidity and as such, are actually not suited to be worn on the human skin. Sweat is not just water and salt, but also contains small amounts of redox-active organic compounds (which act as bactericides). Also take into account that the human skin is constantly regenerating itself, resulting in a supply of microscopic scales that permanently contaminate the beads and, since they consist of organic compounds, may well affect their long-term stability.
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Rock Currier June 07, 2012 07:18PM
After seeing the picture of the pyrite beads, I would recommend that you throw them away and just take the loss. You can of course learn how to use lapidary processes to repolish them, but almost certainly it would not be worth the time to do so and there is no guarantee that the same decomposition process that caused them to degrade would not do so again after you sold them to someone. Here has been considerable discussion here on mindat in various forums about pyrite and marcasite disease that causes these minerals to decompose and people looking to reverse or halt the process. No one seems to have an answer to the problem. My advice is just to dump them and get on with life.

Rock Currier
Crystals not pistols.
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Jan Burch March 15, 2013 05:52PM
Pyrite is so beautiful! I clicked on this blog because of my interest in designing w/pyrite and lack of knowledge in lapidary.

As a jewelry designer, I believe that the simplicity of maintenance (hopefully none is needed!) is just as important as the continued beauty of the piece, and reasonable price point. Right-these are the big three?

Further cleaning of pyrite is a great idea during manufacturing (if it cuts out future black). The application of laquer is something to think about. Lacquer is used often in UK for jewelry. I think some lacquers are better than others and know that sometimes pieces need to be re-lacquered.

Anybody here from the UK? Jan Burch
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Jan Burch March 15, 2013 05:58PM
Pam- I'm very interested in the coating idea. Please inform me if you hear or read anything useful. I'll do the same. Jan Burch
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Sandy March 20, 2013 11:21PM
I am having the same issue. Before I threw out my pyrite beads I thought I would try a stone and grout cleaner. It worked! I just sprayed the beads in a small container, whirled them around for a minute and they came out much shinier! The cleaner is made by TileLab and comes in a bright yellow spray bottle with blue writing. You can just wipe the beads .. no need to rinse!
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Reiner Mielke March 21, 2013 11:51AM
I agree with Rock. It is too late to save the beads once the process of decay starts there is nothing you can do in this case. If it where a mineral specimen for display only there are things you can do, but since these are to be worn those methods cannot be used. Fresh beads that have not yet started to decay can be preserved for a while ( depending on the wear) by coating them in clear lacquer. Generally speaking sulphides of any type are not suitable for beads because any abrasion will produce black powder that will stain skin and cloths.
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Nan Sawyer April 21, 2013 04:34PM
Just began to enjoy designing with iron pyrite. I will try Sandy's solution, but obviously can't put it out for sale. I will keep watch here in case there is a viable answer. In the meantime my family gets it all for birthdays and Christmas.
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Tim Jokela Jr April 22, 2013 04:54PM
Good news, bad news. There is a cure for your pyrite jewelry woes... but only if you don't wear the stuff.

Search this website for pyrite / marcasite disease and the stabilization method proposed by Reiner Mielke. It's very easy, requires nothing more than water, WD-40, motor oil, and a bit of time.

I have used it on a sulfide specimen so rotten that it was soft enough to break bits off with nothing but finger pressure, upon which a half dozen alteration minerals had grown in the decades since it was collected, and enough sulfuric acid had formed to burn thru the cardboard box and stain the drawer bottom.

The treatment was a few months ago, there's no evidence of alteration since then, but I won't call it a success until a few years have passed. Reiner has treated some very unstable marcasite crystals, decades ago, and they're as nice as the day they were collected, so I'm pretty confident it's a winner. Any non-believers out there, get cracking on your pyrite/marcasites before it's too late. Believe it or not, the specimen does not look oiled, or smell bad... I highly recommend the Mielke Method!

So, you can indeed preserve your jewelry pyrite, but, the bad news is, it probably won't last if you continue to wear it. Skin acids, sweat, atmospheric moisture, etc., will slowly attack and alter it.

Some sort of surface coating is conceivable, but I'm not sure if there's anything out there that's been proven to pass the test of time. Perhaps further research into the consolidants used by paleontologists, like Vinac, would bear fruit; fossil and artifact preservation is a big field, they're highly advanced. Of course, if you've done the Mielke Method, then you'll have problems with adhesion of most coatings, unless you clean all the oil off, which removes the protection....

Long story short.... chuck the stuff and don't buy any more jewelry made from pyrite or marcasite.
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John Oostenryk April 23, 2013 06:37PM
As Tim has recently posted too, I guess I will let my cat out of the bag...

re: specimen saving- http://www.mindat.org/forum.php?read,19,149266,page=4
I was quite disgusted when I read Reiner's proposed method with oiling. Good God- that sounds like a complete mess! The guy is crazy...

BUT- after realizing a local connection between oil/bitumin pockets associated with long exposed and completely intact marcasite crystals... and therefore, some later related reflection... I resolved to engage in an ongoing product test with various control groups running.
I only used th WD-40, I couldn't bring myself to do the glooping oil factor...
However, I believe I am at a year and a half and nooothing is changing on my marcasite/pyrite pcs... So good news so far...
...Further details in a separate post are pending...

~JO:)



Edited 1 time(s). Last edit at 04/23/2013 08:52PM by John Oostenryk.
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Maggie Wilson April 23, 2013 08:11PM
Wow, is it just me, or is there an increase in short tempers, misunderstandings and off the cuff comments today? Like John's above and in the other pyrite cleaning thread.

John... could you clarify something? When you write what you said about Reiner, you mean those were your initial thoughts, yes? And now you think maybe, not so much?

I think it would be a good idea to retract, or at the very least, qualify your remarks. On both threads.

Please. And thanks.

Maggie (That's Mrs. Reiner Mielke to you, buddy!) Wilson
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Rock Currier April 23, 2013 08:53PM
Sounds like John is starting to agree with Reinier's way of doing things.

Rock Currier
Crystals not pistols.
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John Montgomery April 23, 2013 09:48PM
John O writes ( regarding Reiner): "this guy is crazy"
No matter if he is starting to agree, he should apologize to Reiner for uncalled for offensive language.
John M.
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John Oostenryk April 23, 2013 10:44PM
Hi Maggie!
Several things to report for you:)
First- I certainly respect you! I have always enjoyed your friendly, positive, and detailed comments. I’m very serious about that and I do value your presence on Mindat!

2) AH-- I knew you were associated with Reiner- now I know how;) You DO know him!
I am very honest, and so I also understand righteous dismay(yours.) Very sorry about that!
I absolutely meant no disrespect, nor trolling, nor anger or anything negative at all!
I have ammended both posts to hopefully more clearly convey myself. I had posted to both threads so that the initial good news would be found in both places.
Really, I thought it was quite innocuous, as it was as anecdote about myself and learning- not about Reiner per se.

That said- well yes, I thought he was something, bizarre maybe! Of course, then, when he first posted, there was a long list of replies, (where I was silent!) which poked fun and refutation. ( I loved the squeaky pyrite one- that was funny!)

Lets not go on about what was simply intended as a humorous anecdote about ME, not him.
An old tune comes to mind, as Steve Winwood sang, ”…at the time I really felt that way, but that was then and now it’s today…”
(I changed my mind right? …and yes, I was laughing at myself as I was dipping my test specimens thinking, dang this is soo gross:)

As Rock noted (Correct Sir!) I really intended nothing but to add support to the utilization of the concept, wacky as it may sound… Don’t knock it till ya try it~ nuff said.

I do plan a written report for the Mindat community in support of the process where I will relate my findings with the local materials here. I’m honestly excited about getting that positive information out to people.
Of course, my support is just a short term data relay. Hopefully, replication of Reiner’s results will be across the board as to locales and duration… Time will tell:)

Sincerely,
~John O:)
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John Oostenryk April 23, 2013 11:05PM
HI John,
I do agree with the positive applications! I didn't really worry about being 'branded as being in the crazy camp' :0
I say that with simple humor intended- poking fun at myself!
There was no insult intended and I believe I have ammended the misunderstanding adequately.
Hope you understand-Have a good day:)
~JO:)
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Reiner Mielke April 24, 2013 12:43AM
Hello John,

Trouble with just WD40 is that it will eventually evaporate and you will be back to square one. Of course you can always reapply the WD40 but it stinks! Believe it or not motor oil does not smell nearly as badly as WD40 and lasts forever ( eventually converting to tar). I also came up with the idea of using oil because I noticed that marcasite associated with hydrocarbons are much shinier and less "weathered". Besides that the chemistry makes sense, no sulphide can oxidize under reducing conditions which the oil provides. Also the mess that pyrite disease makes is a lot worse than a bit of motor oil.
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John Oostenryk April 24, 2013 02:24AM
Hello Reiner,
Regarding the oil factor- Funny thing that! It was today, after Tim's post assured me of the nonresidual state, and I was sorting my reply issue, it kinda clicked that oil would 'fix' that 'light aromatics evaporation' issue that results in the prolonged odor from WD-40. Thanks for the confirmation.
I also concur- WD-40 does eventually dissipate totally- which would necessitate further application- just like any'protectant'. Whereas, as you say, the oil finishes the situation... Priorly, I just hadn't been able to take/make the full "leap of faith" with the heavier(than wd40) oil. It is pending,LOL.

I am currently drip drying after the WD-40 a batch of material that was a basketball size chunk of 100% intergrown stalactitic Linwood Mine marcasite. The decomp odor was really strong in some areas- so correct in nothing to lose:) Dang is it crazy intricate!
Incredibly complex, porous intergrowth. Within the innumerable openings, are innumerable small to tiny scaleno calcites... Its sorta like looking at a human vascular system replaced by a dripping and xtlizng FeS2...
The problem has occurred in past, in some more densely packed pieces where the water rinse leaves water trapped behind some calcite growth, and then oxidation converts to rusting stains. It definitely trashes the appearance, and while I see no way to fully get away from the entrapment, trying anyway! This big chunk already was majorly contacted throughout (how big was the parent???)from blasting. I ran it through a trimmer to open it up more for draining(Pieces are still big.) I have used a space heater set on high to flash as much water off before immersing in WD-40. Interesting too, no thermal damage to the calcites observed so far. (I wouldn't try this stunt on anything you weren't will to lose...) My thinking was hot water for final soak/rinse which promotes evap, then to hot dry air to continue the evap, aided by heat expansion of openings, which would possibly also allow some improved penetration for WD-40 next. Granted, that is prolly just positive thinking(coefficient of expansion being pretty tiny and of nanoshort duration when 'quenched' by the oil).
That initial trapped rusting on this batch, was very minimal compared to volume of success. More results as they become evident.
This will be a part of my 'proposed' and no doubt ridiculously long in images, lil report on your process~

Anyone want some INSANE stalactic/xtline camera fodder, micro/thmb Marcasite xtls? PM me for trades or whatall. It HAS been fun monkeying with it so far! Nuff bout that portion...

My correlation epiphany came from material from the southern edge of UMV type deposits just N of me. First portion was that the crystals were in exposed vugs in rock that was being immersed repeatedly for extended periods by extra scummy flood waters of the Mississippi River. That rock was dumped over 20 years ago. Anything below flood level that was unstable was just a reddish stain... And then there would be a cluster of stable xtls! WTH? Occasionally there would be gooey bitumin on rocks. I thought it was sloppy seal coat asphalt from the adjacent road, till splitting a boulder produced both gooey tar and light oil, with a nice pyrite cluster inside it! That got the seed to growing on hows and whys... It was timely that you had recently described your successful application... Following all that, I happened to make a huge find of intergrown pyrite and marcasite from a clay deposit in a regional quarry. I had a ridiculous quantity to sort out and THAT was when I decided to test the idea in full. I had mostly stable stuff, but some was clearly bad and some was shifting... So plenty of guinea pigs!
I guess you could say the rest of the story is becoming 'history', the WHOLE good kind, and not the disintegrated BAD kind...
Yes, obviously, in retrospect, your hypothesis on reduction and environment do make sense:) Good stuff!
More details eventually of course...
Thanks!
~JO:)



Edited 1 time(s). Last edit at 04/24/2013 02:30AM by John Oostenryk.
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D Mike Reinke April 27, 2013 05:55PM
Reiner, and John, et al-
You mention 'marcasite association w/ hydrocarbons' made a light finally go off in my brain-duuuh! I've seen that. Walking the Lake Michigan beaches, there are lots of rocks that have small cavities of oil in them, or drier tar. A few years ago I picked up a softball sized broken rock w/ a pyrite lined cavity, but solid with tar. I recently cleaned the smaller chip, and it is lined with dazzling blades of marcasite. I gave the bigger chunk to a friend for his yard, now I need it back!
But how do you clean out the tar? I soaked it in gasoline, WD40, simple green, hot water, a few other chemicals, yes, it stinks, and it took a long time. Soaking overnight only made slow progress each night. Is there an easier way? Doesn't sound like it...
John, your stuff sounds cool. I may be out your way next month-ish! Can't plan anything right now...

Mike
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Tim Jokela Jr April 29, 2013 06:01PM
Experiment with iron out to remove rusting after the water soak. It worked great on my piece, I watched the tarnish disappear in, literally, about 10 seconds. Then scrub, dry, and into the WD-40. I'm not sure if you have to be religious about getting it dry before the WD-40; the whole purpose of the stuff is to displace the water.
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Feanne July 02, 2013 09:21AM
Does anyone have tips for preserving pyrite specimens? I have just one pieces for my collection, it's either in storage or display. If in storage should I keep it in an airtight container and in the dark? For cleaning, can I just use water and mild soap and gentle scrubbing? Any tips would be appreciated since I'm a total newbie :) thanks!
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Lindaluv January 28, 2014 06:02PM
I was at a market recently, and found a stunning pyrite pendant bead for sale.
I decided not to purchase before researching pyrite - being "buyer beware".

Is there any further/recent news regarding the prevention of oxidization/decomposition with e.g. Lacquer??
Also, would a coat of clear nail polish qualify as lacquer?

Thanks for any advice.
Appreciating the comments above.

cheers,
Linda :)-D
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Ed Clopton January 28, 2014 07:21PM
For the sake of completeness, people who don't have first-hand experience with deteriorating pyrite & marcasite should be aware that in addition to the white sulfate efflorescences that form on surfaces, another byproduct of the process is sulfuric acid. Many a paper container, egg carton, specimen label, etc. stored with unstable sulfides at least has been stained, if not crumbled completely to bits, under this quiet chemical assault. So if you are storing pyrite or marcasite, put a layer of plastic between it and the outer container--and other nearby containers and specimens--to protect them from acid attack.

Something else I haven't seen mentioned in this particular thread is that susceptibility to "pyrite disease" seems to depend in part on crystal grain size. Deterioration seems to happen on the surfaces of, or at boundaries between, individual crystal grains. Well-crystallized material consisting of one or a few crystal domains has less crystal surface area available to chemical attack, whereas massive material consisting of a multitude of tiny crystal grains has much greater surface area in a given volume. Therefore a single-crystal cube of Spanish pyrite should be relatively stable, but a cubic bead of the same size cut from similar polycrystalline material (or a fossil replaced by tiny pyrite grains) is much more vulnerable to deterioration. A great many of the beautiful pyrite "sunflower" concretions unearthed during construction at the Dallas-Fort Worth Airport in the early 1970s, and similar specimens from many other places, have disintegrated. The big cubic crystals around the edges survived individually, but the concretions were destroyed as the finer-grained centers deteriorated, swelled, and broke apart.
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John Oostenryk January 29, 2014 06:07PM
Old thread with a bit of activity;) I'll wrap up...

A) I guess everyone figured if Feanne didn't take the time to read the whole thread- no sense in bothering to reply! Ditto myself back then...

B) Hi Lindaluv! You read through~ You get a reply! LOL

You weren't clear on whether this was a completely ground/polished piece- or a 'freeform' cab with natural crystals exhibited and a ground back/sides/ whatever... Either way though... Hard telling as to longterm stability!? Sorry- the answer is there isn't a definite one...

My gut tells me- it will likely tarnish at some point at best. You make the call on cost vs utility. $5 and you wore it sometimes for a year??? Cool! $20 and a year?? ...That's your call.... Doubt it is something that will be passed down as heirloom.
The "marcasite' 1920's jewelry doesn't look as blingy today as back then. But that stuff, if whole now- it will probably stay that way...

Yes clear nail polish could be considered modern laquer.

It would surely prevent the dark ruboff if applied to back side(of a nat cab)~ it would help with same on finished piece, but would look funky painted over crystals though, IMHO....

HOWEVER- As stated in thread repeatedly-Might? slow issues but is NOT a cure~ IF it is "gonna go bad". BUT- you can stop that decomp with the oil treatment as stated above. I am 100% sure on that.
You will have a greasy spot on your blouse though- Not good!;)-

I'd pass on that jewelry option! Buy a blingy specimen-set it in a sunny spot! Treat it if it starts to act funny- Keep on enjoying it!

~JO:)
ps: Argh- I still haven't written up my continuing-ongoing marcasite preservation experiment... stupid promise... darn report... LOL
Maybe after Tucson2014... Looks like I am heading that way?! YAY... Maybe during the drive as passenger:)
Don't hold your breath-but eventually!
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Rock Currier February 24, 2014 09:45PM
Could you upload a picture of the pendant? Did the seller say where the "pyrite" came from?

Rock Currier
Crystals not pistols.
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Stephanie Ah February 03, 2018 05:40PM
Hello Reiner,

Newbie here. I have tried various search terms, but can't locate your post about cleaning pyrites/marcasites with wd40/or oil. Would you mind posting the link? (if allowed) Very interested in reading about that.

Thanks in advance,

Stephanie
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Reiner Mielke February 03, 2018 07:56PM
First you wash all the oxidation off and soak the piece in water for a few days. Then you dry the specimen and submerge it in a water displacement protectant like WD40 for a day or two. Then you dry it and then submerge it in clean regular motor oil for a few days. After you take it out of the oil you set it in the sun on something absorbent and let the motor oil drain for a few days. The motor oil gets into the cracks and leaves a thin film on the surface that creates a reducing environment, end of problem.
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Luca Baralis February 03, 2018 08:03PM
Interesting. But the oil doesn't leave a residual film on crystals? And I presume this method doesn't fit if there are also others minerals, say calcite...
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Reiner Mielke February 03, 2018 08:08PM
It leaves a film you cannot see (which protects it) and there is no problem with other minerals that are commonly associated with iron sulphides other than those that are water soluble.
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Stephanie Ah February 05, 2018 11:26PM
Very interesting! Thanks so much for explaining this, Reiner. I will surely try it. I just bought a really nice small Peruvian pyrite display piece that looked very much like a shiny gold ingot in the sales photo (attached). I was a bit disappointed to find that it has some traces that look like the kind of Calcium deposits left behind by hard water. You couldn't see those on the photo. Although, admittedly, a more practiced eye than mine may have known what to look for.

I didn't want to mar the surface by scrubbing or rubbing it. Which is why I stumbled on this thread. I have all fingers crossed that this treatment will get rid of that slight deposit and give me my "gold ingot".
open | download - Pyrite ingot.jpg (33.7 KB)
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