Pyrite with salt expulsion

[MEHo]

Hello,

Some years ago I bought a pyrite form Tsjechia. But now I got a problem: I think it is 'pushing out' salt and is crumbeling into dust very slowly. You can see that little white (salt) cristals are growing on the stone. But how could I stop it? Because I'm afraid that it wil rust when I put it in water for a couple of weeks. Does anywone have an idea?

Greetings, MeHo

[Ralf]

Hi MeHo,

I´m sorry, but you have no chance to stop this process. May be you havn´t Pyrite but Marcasite. But anyway. The reason is a high sulphur. This will be decompose the Marcasite or Pyrite. This process is well known for Marcasite, may be it´s the same for Pyrite. I dont know.

Sorry
Ralf

[MEHo]

Yes, you could be right. It gots some yellow spots on it. But I'm not sure it is Marcasite, because it has cubic looking cristals. Though it is a little grey. I'm afraid it will not take long, before it is dust  . But anyway, thank you for the information!

                                                                                                                    Greetings, MeHo

[uwe]

Hello MeHo,

I know this process because  I subervised it at a specime from Ronneburg yeas ago, too. It was very interesting this quick generation of new minerals but at last it was a mixture of different unstable minerals.

I assume the white crystalls are alum. But be carefully. At this process  also acids are generated which may destroy something. Better you put the specime on a small ceramic or glass plate and whatch the process.

Best Regards
Uwe

[wolfi]

Hi MeHo,
i think your pyrite is from Sokolov near Cheb. I had some of these in my collection, too. But meanwhile they are destroyed completely. The pyrites come from a brown coal quarry, i believe the coal is the reason for this desaster.
Servus + Glück auf
Wolfi

[MEHo]

Thank you for the information! I don't think it will take long, before my specimen is broken. Because it has a big crack in the middle. To bad  :'(. But anyway, it is very interesting!

(p.s Next time I inspect the mineral, I think I will wash my hands more proparly  )

                                                             Greetings, MeHo

[MEHo]

I made some fotos of it. On these fotos you can't see the crack.

The front:



The back with the little with crystals:



srry, for the bad quality. My digital-camera isn't that great 

[uwe p.]

...trying to remember what i should have learned at school...

the high sulphur part is not the problem, it´s the steam in the air which makes your pyrite getting crumbly - and i guess, the flavour is very bitter & aggressive (resulting from the H2SO3, i think...)
so, the sulphur and the steam cause a sulphurous acid (H2SO3, not H2SO4) precipitation which disbands yout pyrite.

putting the speciem into a glas//plastic box should help (well in this case everything seems to be lost anyway...) to keep the steam away and avoid the destrucion.

another way of conservation is to work with clear varnish, invisible and save.

should work,
have a nice day!
uwe

[MEHo]

K, thank you for the information  . I was planning to put it in a plastic box or something. But I don't have wone right now. It now is behind glass, but it still can come in touch with air.
I hope I get a box soon, so i can save it from complete deconstruction  . 

                                                Greetings, MeHo

[Galenit]

You cant this way.
Once the Prcoess has began, you nearly cant stop it. Nothin like closing it from fresh air, or anything else will help. There are only a few ppls who can stop it, and it take some month and is very expensive, so its just an option for really good and expensive Mineral specisms...

[Galenit]

You cant this way.
If you would have put it into a glass container without fresh air and oxygen, directly by finding it, you could have prevented it. But once the Prcoess has began, you nearly cant stop it. Nothin like closing it from fresh air, or anything else will help. There are only a few ppls who can stop it, and it take some month and is very expensive, so its just an option for really good and expensive Mineral specisms...

[MEHo]

Little bit confusing, all these different stories  . But anyway I now assume I can not stop the proces, and that it wil be gone after some time. ( and thx for the info, offcourse)

                                                                                                           Greetingd, MeHo