# Of pipes and crystals



## Owltech (Apr 22, 2018)

Precipitated with oxalic acid


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## denim (Apr 22, 2018)

Wow! Really nice. Very well done. Nice size little button you got there 8)


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## aga (Apr 22, 2018)

Beautiful !


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## cosmetal (Apr 22, 2018)

:shock: Impressive! :shock: 

Origin?

Karat scrap, gold-filled scrap or electronic scrap?

James


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## goldsilverpro (Apr 22, 2018)

That's the way buttons and bars should look. Crystal and pipe. I never liked bars with those concentric swirls. They're pretty but I don't trust them. With big crystals and a deep pipe, you know the purity


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## g_axelsson (Apr 22, 2018)

Just beautiful!

'nuff said!

Göran


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## Shark (Apr 22, 2018)

Very Nice!


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## Owltech (Apr 23, 2018)

Thanks everyone! The gold was recovered from electronic scrap: fingers, pins and CPUs.


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## Owltech (Apr 29, 2018)

button, in the making:

https://youtu.be/_DILKWccPQ8


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## Palladium (Apr 29, 2018)

[youtube]http://www.youtube.com/watch?v=_DILKWccPQ8&feature=youtu.be[/youtube]


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## cuchugold (Apr 29, 2018)

With that voice you can get a $500,000 a year job as a radio host!. :G

Great collection of refining videos too!. :G :G :G


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## goldsilverpro (Apr 29, 2018)

Owltech said:


> button, in the making:
> 
> https://youtu.be/_DILKWccPQ8



I removed the youtube brackets from your link to make it wprk


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## LT_golden (Nov 4, 2018)

Hi OwlTech,



Owltech said:


> button, in the making:
> 
> https://youtu.be/_DILKWccPQ8



That not-small-at-all button is ridiculous. I mean that in a grandly positive way, but just... ridiculous.

So I’m still recovering my gold for the first time, and studying up to refine/melt for the first time, too. I wanted to pour the molten gold into a cylindrical quartz mold, and I want to create the crystalline surface.

I was thinking, surround the mold with red-hot charcoal while I melt the gold, then after I pour, remove all the the pieces of charcoal closest to the mold, and just let the charcoal slowly die, thereby letting the gold cool slowly like that. Might take some time... but beers and snacks with friends makes for a shorter wait. :lol: 

But I could think of a few questions...
1) Would I be able to get the crystalline surface, have no unattractive cavities, and still have the overall shape be that of the mold?
2) When the gold & quartz mold finally cool, would I have trouble removing the gold? Whenever Hoke mentioned using a quartz crucible she almost always said to just break it to get the gold.
3) In case I won’t be able to remove the gold from the quartz mold, what’s a safe way to break it without denting or deforming the gold...?

Thanks a lot for your help. I hope mine comes out as nicely as yours...!


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## 4metals (Nov 7, 2018)

It appears that the scene where you add sulfamic acid to de nox the solution you are doing it on a table which apparently is not under a hood. The reaction forms nitrous oxide, which isn't the best to breathe. 

With HNO2, sulfamic acid reacts to give N2, while with HNO3, it gives N2O.
HNO2 + H3NSO3 → H2SO4 + N2 + H2O
HNO3 + H3NSO3 → H2SO4 + N2O + H2O

They don't call it laughing gas for no reason.


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## LT_golden (Nov 7, 2018)

4metals said:


> They don't call it laughing gas for no reason.



Hey 4metals,

Had it ever occurred to you that he might’ve done it on purpose, and that the nitrous oxide effects lingered all the while he was editing the video?

I mean, he _did_ entitle the post “Of _pipes_ and crystals”...

—Luke


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## Lou (Nov 7, 2018)

Hilarious reading...

https://publicdomainreview.org/2014/08/06/o-excellent-air-bag-humphry-davy-and-nitrous-oxide/

Apparently it was all the rage back in the day, and hurt him not in the slightest. 
Really, there are far worse things to inhale than laughing gas (especially if you're hypertensive, it may actually help you!)


*In all seriousness, any N2O produced by sulfamic must be avoided due to entrained precious metal aerosolized mists!*


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## Owltech (Nov 10, 2018)

4metals said:


> It appears that the scene where you add sulfamic acid to de nox the solution you are doing it on a table which apparently is not under a hood. The reaction forms nitrous oxide, which isn't the best to breathe.
> 
> With HNO2, sulfamic acid reacts to give N2, while with HNO3, it gives N2O.
> HNO2 + H3NSO3 → H2SO4 + N2 + H2O
> ...



Hi! Thanks for your concern, all procedures (digestion, de-NOxing, filtration, precipitation and washing) are performed inside a hooded cabinet. It doesn't look this way because the camera itself is placed inside the cabinet.  



*The videos can't and don't show everything*, that's why (IMHO) they should be used only as reference rather than "do as shown"


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## Owltech (Nov 10, 2018)

LT_golden said:


> Hi OwlTech,
> 
> 
> 
> ...


Hi!
1. Don't know the answer to your question.
2. Yes I think both gold and crucible would suffer 
3. Don't know of a safe way to do it.

Not much of a help, sorry!

I always leave my gold to solidify inside the crucible, then quickly pry it out before the borax solidifies


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## LT_golden (Nov 12, 2018)

Owltech said:


> Not much of a help, sorry!
> 
> I always leave my gold to solidify inside the crucible, then quickly pry it out before the borax solidifies



That’s alright, thank you anyway for replying.  I’m thinking of trying thermal shocking the quartz — that is, after the gold has slowly cooled to form the crystals etc. that I’m after, then torch the quartz again and then dunking it into ice water — repeatedly, to crack/break it without exerting external force inwards to break it.


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## Lou (Nov 13, 2018)

Depending how pure the quartz is, that may be a wasted effort.

I take my quartz stir rods from pushing down Pt sponge into the molten Pt in the induction melter and put them in ice cold water and they do not crack.

Tell you what though, if you have grab the end of the rod with your glove and not the outside of the rod, the light transmitting fiber optically up the rod will singe you!


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## goldandsilver123 (Nov 14, 2018)

Lou said:


> Depending how pure the quartz is, that may be a wasted effort.
> 
> I take my quartz stir rods from pushing down Pt sponge into the molten Pt in the induction melter and put them in ice cold water and they do not crack.
> 
> Tell you what though, if you have grab the end of the rod with your glove and not the outside of the rod, the light transmitting fiber optically up the rod will singe you!



That's quite a thermal shock, ~1700 ºC! I knew that quartz handled 1000ºC but 1700 it's almost double.

You must stir it very fast, fused quartz doesn't melt at 1650ºC?


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## Lou (Nov 14, 2018)

It does melt somewhat but even at the melting point of Pt pure SiO2 isn’t exactly very fluid. Also, it loses quite a bit of heat (as light) at the other end!


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## LT_golden (Nov 17, 2018)

Lou said:


> Depending how pure the quartz is, that may be a wasted effort.
> 
> ...
> 
> Tell you what though, if you have grab the end of the rod with your glove and not the outside of the rod, the light transmitting fiber optically up the rod will singe you!



Hi Lou,

Thanks for the rather interesting and seemingly hilarious (though true) reply.  

So what about molten sodium hydroxide? Letting gold cool and crystallize inside the quartz tube to ambient temperature, then chuck the whole thing into a steel pot of molten sodium hydroxide... dissolving the quartz but keeping the crystallized gold untouched?

If this would indeed work, then how would one go about cleaning any residue of the glass from the gold, for example, in the crevices of the crystallization?

Thanks a lot for the help. 8)


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## Owltech (Nov 19, 2018)

NaOH will work, not the safest method, but indeed molten caustic "eats" through quartz (from experience). Not sure if the gold would remain unaltered.


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## Lou (Nov 19, 2018)

Gold is immune to caustic, all concentrations, all temps.


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## LT_golden (Nov 20, 2018)

Hi Lou and OwlTech,



Owltech said:


> NaOH will work, not the safest method, but indeed molten caustic "eats" through quartz (from experience). Not sure if the gold would remain unaltered.





Lou said:


> Gold is immune to caustic, all concentrations, all temps.



Thank you for your help, both of you.  So could dissolved glass solution get caught in the crevices of the solid gold? Would it be easy to clean with just water rinses? Would it need to be hot water? Might soaking be required?

I'll be trying out first just normal tap water rinsing, and posting my results... once I get to that point.


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## Owltech (Nov 21, 2018)

Nothing that a prolonged boiling in dilute HCl can't fix.


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## LT_golden (Nov 21, 2018)

Owltech said:


> Nothing that a prolonged boiling in dilute HCl can't fix.



Hi OwlTech,

Did you mean boil or simmer? Wouldn’t boiling cause some little bit of oxidization and the HCl taking away a little bit of gold...?


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## g_axelsson (Nov 21, 2018)

No, it won't oxidize and be dissolved. Gold isn't that wimpy.  

If you want to be on the safe side, just test with stannous and put the acid in your stockpot (for finer particles to settle) or use it for the next batch of gold you refine.

There is one instance when you might get a bit of dissolving, and that is if you have it standing beside a beaker with nitric acid for a longer time. The acid can move from beaker to beaker as vapor.
I have seen it the other way around once, a beaker with silver nitrate turned misty from silver chloride caused by HCl vapor from another beaker.
But even then it is just a minor effect of no concern.

Göran


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## Lou (Nov 21, 2018)

The whole “gold into HCl issue” is more for cold, c HCl that can have some level of dissolved chlorine, and really only with gold sponge.

Hot HCl has all the oxygen and chlorine boiled out of it...no effect on gold.

I’ve been thinking...a fun test would be to see how large a pipe one can get in as big a button as possible.

Hmmm!!


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## LT_golden (Nov 21, 2018)

Lou said:


> The whole “gold into HCl issue” is more for cold, c HCl that can have some level of dissolved chlorine, and really only with gold sponge.
> 
> Hot HCl has all the oxygen and chlorine boiled out of it...no effect on gold.
> 
> ...



Hi Lou,

Okay, I just thought that the bubbling from boiling would increase solution surface area and the dissolution of air into the solution, increasing chances of oxydizing gold molecules and their binding to the chlorine atoms. I’ll not worry about it then since both you and Göran have said it unnecessary. Besides, there’s always the stannous chloride test.

About the pipes... Hellz yeah! That’s the whole point of my trying to cool the gold as slowly as possible, inside the little quartz tube and surrounding with coal and letting it burn out and cool in ambient air! Though I wouldn’t have that large of a button myself... What would your method be to try?


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## Owltech (Nov 22, 2018)

LT_golden said:


> Owltech said:
> 
> 
> > Nothing that a prolonged boiling in dilute HCl can't fix.
> ...



I don't think there will be a problem


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## Owltech (Nov 22, 2018)

Lou said:


> I’ve been thinking...a fun test would be to see how large a pipe one can get in as big a button as possible.
> 
> Hmmm!!



Things that make you go hmmm!! Ca plane pour moi https://www.youtube.com/watch?v=aBOVMWDTfDU


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## Owltech (Nov 29, 2018)

In the meantime...











https://youtu.be/yAroXoqYOec


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## anachronism (Nov 29, 2018)

That's really good. However can you tell me why in the scheme of practicality how it's any better than precipitating by other means?


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## Owltech (Nov 30, 2018)

anachronism said:


> That's really good. However can you tell me why in the scheme of practicality how it's any better than precipitating by other means?



Initially this gold was precipitated with SMB, but due to PGMs contamination I had to redissolve it and use different precipitation agent (oxalic acid). The starting material was 4kg fingers from various boards, some of which with Pd plating.




All I'm trying to say: sometimes the use of different precipitants is necessity rather than a whim.


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## anachronism (Nov 30, 2018)

Ahh yes now I get it. Thanks !


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