# Re: Precipitating gold from dirty AR



## jmarsden (Dec 14, 2012)

Hi there, I am in a bit of a pinch and need some guidance from the veterans on the team. I have a very rich deposit of ORE that I have been working on for several years and finally developed a process for getting the Gold and other PMG's out. The assay's on the final dore are astounding. At this point I am only interested in the gold. The process requires inquarting of tin into the flux and in every case we have a pretty good gold yield. 

I have been working on several refining options and have determined to run some tests with an AR solution. To pull the gold out using electrowinning and also try a precipitant. 

I have two questions:

1) Chemistry solution -Should I deal with the tin before putting into AR if so how? If not, what processing technique would work best to deal with the tin?

2) Electrowinning solution - I am looking for a provider of good "Selective" diode components for this process 

OR AM I COMPLETELY OFF MY ROCKER?
James


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## nickvc (Dec 15, 2012)

As I said on your other post you want rid of that tin if you want to recover all of your gold. You could try corn flaking the bars and putting in hot hydrochloric until all reaction stops, I would do this at leat twice, if that fails maybe have the bars rolled really thin and try the same procedure with the hydrochloric, you must get rid of all the tin to avoid losing values.


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## Palladium (Dec 15, 2012)

What percentage of it is tin?
Wouldn't copper work as a collector also?


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## jmarsden (Dec 15, 2012)

Yes, so once I have prepared the ORE. Then I prepare the flux. Scaled down of course I add to the top of the flux 180 grams of tin. When the burn is complete I ended up with 182.5 grams of material. So there is a 2.5 gram yield, mostly gold and some silver.

Nick, did you mean to advise HCL as both solutions??


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## g_axelsson (Dec 15, 2012)

This is just a far fetched idea that I have never tested and it probably won't work anyhow... but ...

If you really need tin as a collector, then maybe the solution is to try to mimic an old method for silver extraction from led. It was used for a long time before electrolytic refining were invented.

If you reuse the tin as a collector until it becomes almost saturated with silver and gold, then you take it out and process it by melting it but keeping it just above the melting point. Hopefully you will lower the solubility of gold and silver in the tin melt and it starts to form crystals from gold and silver. After keeping it at a very exact temperature the melt could be filtered in a stainless sieve, leaving silver and gold behind. Or even decanting the tin could leave crystallized gold at the bottom of the melting pot. The tin could be reused for collecting more values.

As I said, this is just a far fetched idea based on the old silver reclaiming method. In that process they were helped by silver crystals being lighter than lead and floating up to the surface, making it "easy" to just skim off the silver from the top. As both silver and gold is heavier than tin it will sink to the bottom of the melt so if you heat it from below it will redissolve the metals in the hot spot.

Getting ready to be slapped around for my crazy idea. :mrgreen: 

/Göran


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## nickvc (Dec 16, 2012)

Goran I like the idea and I can see it might work there's also a method called liquation where the material is heated on a sloping surface at the melting point of the tin and it slowly runs off leaving the impurities in this case the values behind. The other thought I liked with your idea was to reuse the tin in multiple melts, if the material is prepared and the flux put on the top then just put the bar onto the top and melt, trials would be needed to see if the recovery was as good which could be simply weighing the resulting bar until it starts to be ineffective as a collector. At some stage a full removal of the tin content will be needed and here hydrochloric might be the answer unless electrolytic refining is used but even then I can see that it's still going o be necessary to dissolve any tin in the slimes with hydrochloric. There's seems to be methods available to the home refiner to accomplish this reasonably cheaply and farly easily.
Trials are going to be needed so keep us all informed of your progress and I'm sure more ideas and help will be available, good luck.


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## jmarsden (Dec 16, 2012)

Thank you so much for you input. I could have been a little more clear up front but maybe this will help a little. I think you are describing to some degree at least the way we are conducting our burn. We are putting the prepared ORE on the bottom of the crucible, the adding the (mixed) flux on top of that, with the tin sitting on top of that. Then of course a layer of Borax is the final layer. 

And with this process we have the yield mentioned above. Yesterday as a matter of interest, I ran three different tests on the dore with varying results. Maybe you could respond.

1) Tried a nitric rip down which caused the tin to become stannous oxide as expected. Then I washed with water and dissolved the stannous oxide in HCL gently heated. The outcome was that the tin was completely dissolved and left a residue of precious metals. Since this was a very small sample (just a few shavings) I have no way to validate the precise yield.

2) Tried straight up AR and tried to precipitate with SMB and had very little drop out however there was some.

3) Tried an HCL rip down. Heated the sample up to boiling in HCL for several hours. I think my sample was to small so I am running this again on Monday. 

Your feed back on all of these would be well received.


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## jmarsden (Dec 16, 2012)

I forgot to say that the real IP in what we are doing is in the ORE preparation. I have run tests with led as a collector with not nearly the same results. I just ordered silver, bismuth (for a led/bismuth alloy trial), and finally copper. I'll keep you posted on the results of these as collectors. Not sure how much to inquart with each of these but I would assume the same values that we finally arrived at with Tin. I will say that inquarting with led (alone) didn't work at any level.


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