# Stannous Chloride test after gold drop



## wct0415 (Jul 27, 2011)

I just finished my first large precipitate of gold using SMB. After using my vacuum funnel and assuring all gold powder has been removed from solution I did a Stannous Chloride test of my waste solution (approx 3 liters) and came up with a medium to light brown. From what I have read and been researching on this I have come to the conclusion that I have Pd left in solution. From what I have read several time is that it does not drop from this highly dilute solution. Can the values be dropped with iron, zinc or DMG and do I need to reduce my liquid considerable to accomplish. 
I processed mixed high karat gold with some 10K and one ring of white gold 14K, inquarted to <6K disolved in nitric to drop gold, rinsed, washed with HCL and then Ammonia and washed again and melted 3 beautiful bottons 2 @ 15.6 grams and 1 @ 10.4, (will post pictures later).
Back to my question on what to do with the 3+ liters of SMB with the Pd and how can I recover the values.

Thanks for you assistance that any may be able to guide me in the right direction
Bill


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## philddreamer (Jul 27, 2011)

Hi Bill!

I highly recommend you get a copy of Lazersteve's video on Pt & Pd recovery & refining.
Also, read, read, read; this forum is loaded with the information you need, but it takes searching of your part.

Take care!

Phil


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## dtectr (Jul 27, 2011)

How much SMB did you use to drop your gold? An excess of SMB can sometimes give a false positive.

Did those buttons all come from one batch? :mrgreen: :shock: Sweeeet, can't wait to see 'em.


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## samuel-a (Jul 27, 2011)

Pd usually flashes a dark color upon addition of SnCl (black/ brown/ orange), depends on concentration... 
Pd, in most cases will creat blue/green stain after few minutes.

If the brown color is presistant (5-10 min. with no change), then it is probably what dtectr suggested.


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## wct0415 (Jul 28, 2011)

dtectr said:


> How much SMB did you use to drop your gold? An excess of SMB can sometimes give a false positive.
> 
> Did those buttons all come from one batch? :mrgreen: :shock: Sweeeet, can't wait to see 'em.



I divided the solution into 3 separate 1 ltr beakers each with about 600ML of solution, to those I dissolved 2 1/2 teaspoons of SMB into 250ML H2O. In each case the reaction was very responsive and I really didn't need to add the entire amount but did just to assure all gold was dropped. The brown color did not change with time, it is still just as brown as the day I did the test. False positive for Pd so I can dispose of the waste, thanks

And yes they all came from one batch.
Bill


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## samuel-a (Jul 28, 2011)

Before tossing the solution, you can hang a flat piece of copper and see if there any cementing going on within hour or two.


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## eeTHr (Jul 28, 2011)

Here are a couple good pages about testing and the resulting colors, and unusual conditions---

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=41&t=5271 (Includes photos.)

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=39&t=646&hilit=testing+with+stannous+chloride


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## qst42know (Jul 28, 2011)

> I processed mixed high karat gold with some 10K and one ring of white gold 14K, inquarted to <6K disolved in nitric



Properly inquarted the palladium if present is with the silver.


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## freechemist (Aug 10, 2011)

Hi wct0415,

Pd, if there is, can be precipitated with DMG (bright yellow, sometimes greenish, if traces of gold are present, voluminous precipitate), even from very dilute solutions. This is a well known, very sensitive method also to even detect small traces of palladium in qualitative analysis.


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