# Dissolved crushed rock



## ZK1 (Jun 24, 2016)

Hi everyone.
I dissolve a crushed rock in AR. Filtered the solution, and got yellow substance.
After adding couple of drops stannous, color of substance changed to dark brown.
Is it possible that, there is gold in it?
Thanks


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## ZK1 (Jun 24, 2016)

This is a rock that was used.


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## archeonist (Jun 24, 2016)

Why didn't you drip some of the solution and the stannous on a piece of paper?


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## ZK1 (Jun 24, 2016)

Well, this is only a part of rock and of solution on the pictures, I still have about 32oz of yellow liquid left.


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## Geo (Jun 24, 2016)

It's not a positive. The odds of just dissolving gold from crushed ore with acid is very slim. Even pure HCl and nitric acid will turn yellow just from mixing them together.


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## ZK1 (Jun 24, 2016)

This is a picture of stannous test on a plain paper.
Thanks


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## Geo (Jun 24, 2016)

That yellow looks like dissolved iron to me. Many elements give a yellow solution. The stannous test is a false positive.


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## mls26cwru (Jun 24, 2016)

I would be inclined to agree with Geo especially since he has more experience than myself.

From my experiences, a solution that has enough gold in it to make it look 'that' yellow would have a jet-black stannous test... I would be thinking its a false positive. 

Hopefully a few more will chime in with some thoughts... I know there is some funky chemistry that can go on with ores though.


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## FrugalRefiner (Jun 24, 2016)

My advice would be to get an assay before you start crushing rocks and putting them in acids. Here are a couple of threads that may help.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=60&t=23926
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=47&t=21412

Dave


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## Barren Realms 007 (Jun 24, 2016)

HCL by itself will turn yellow once oxygen gets to it.


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## jason_recliner (Jun 24, 2016)

Barren Realms 007 said:


> HCL by itself will turn yellow once oxygen gets to it.


 :idea: So that would be the colour of chlorine being released! This completely answers several questions that I didn't have until right now. :lol:


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## goldknuckles (Jul 3, 2016)

No pay dirt, but see for yourself and dry it then hit it with a torch. No wait, I don't mean actually hitting it. I have a jar of bench sweeps that I know has at least 15 dwts AU in the mostly decomposed granite/dirt that I sweep up around my jewelers bench. I was planning on eventually refining it with AR. With all safety checks in place, what could possibly go wrong?


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## Barren Realms 007 (Jul 3, 2016)

goldknuckles said:


> No pay dirt, but see for yourself and dry it then hit it with a torch. No wait, I don't mean actually hitting it. I have a jar of bench sweeps that I know has at least 15 dwts AU in the mostly decomposed granite/dirt that I sweep up around my jewelers bench. I was planning on eventually refining it with AR. With all safety checks in place, what could possibly go wrong?




Everything if you don't read and study to learn what you are doing. There are procedures for dealing with sweeps that need to be followed. If they are not followed you will create a giant headache for your self and cause you problem's recovering your gold and PM's.


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## ZK1 (Jul 3, 2016)

Hi all, this is precipitate from same solution with SMB. Solution getting green color while precipitate is collecting. But I'm getting light brown precipitate. What can this light brown means. Thanks


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## Barren Realms 007 (Jul 3, 2016)

ZK1 said:


> Hi all, this is precipitate from same solution with SMB. Solution getting green color while precipitate is collecting. But I'm getting light brown precipitate. What can this light brown means. Thanks



You will need to do more testing of the sediment to find that out.


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## nickvc (Jul 4, 2016)

I have to ask this, whatever made you decide to put an unknown piece of rock that may or may not contain values into acid, there could be lots of very nasty and toxic elements present that become highly dangerous once exposed to acids, the values may or may not be dissolvable but could also be totally non reactive to the acids without extra treatments.
We have had one new member do exactly this before not too long ago,who is now very ill, despite the warnings we tried to give him.
Stop messing with acids and reagents until you know what you are dealing with or you could become another accident with serious health issues or worse.
Get a proper assay and know what you have.


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## Geo (Jul 4, 2016)

Arsenic comes from the ground in the same deposits as gold.


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## worldavi (Jul 24, 2016)

Geo said:


> It's not a positive. The odds of just dissolving gold from crushed ore with acid is very slim. Even pure HCl and nitric acid will turn yellow just from mixing them together.



Why do you say that crushed ore with acid would be very slim. The natural process of gold deposition is by acidic solutions leaching gold from the surrounding rock right? If its high grade ore 2 or3 oz/ton ....why would this not work for him??


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## Topher_osAUrus (Jul 24, 2016)

Just a guess. But probably because all of the other elements composing the ore are more reactive than gold, so they want to go into solution before the gold. And If theres any carbon, it will absord/adsorb the gold.
Also, putting some toxic elements into solution can be detrimental to one's health.

Standard practice is "standard" for a lot of reasons. Not dying, and not losing gold are two that come to mind right off the bat.


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