# Hcl-cl On Paydirt



## chrishawn (Jan 22, 2012)

Hi everyone,
I Have a bit of paydirt that i panned on a vaca. After pulling all my gold out i noticed some very small material that looked like gold but not sure so i brought it home to process in Hcl-cl, and after clorine evaporate, added smb to drop gold.After about 12 hours solution turned clear purple,
its been 4 days now and gold is taking along time to settle. It is setteling,
just taking a long time.My ? is why.
When i usually prosses gold from escrap the gold will drop in about 1 day.
Any sugestions or comments will be greatly appreciated
Thanks


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## butcher (Jan 22, 2012)

chrishawn, 

You are making it hard for us to give you an educated guess, I would need to know more clues to this puzzle.

This panned "pay dirt", are you sure it was really gold?

When I pan gold there is no mistaking for me if it is gold or pyrite.

I do not know how much experience you have panning, but most people, who are not regular miners, mistake pyrite for gold.

Did you try and smash your gold? Were you able to pan out the rocks and sand from this gold, how much black sand, or other minerals or materials did you try and dissolve with the pay dirt gold?

How clean was this pay dirt before you tried to leach it with HCl/Cl?
What did your stannous chloride tell you when you had it in solution, and how is the stannous chloride test reacting now.

Did you eliminate the free chlorine, before trying to precipitate? 
How did you calculate the amount of SMB needed and used?

Sorry I do not have answer's, I just many questions. 
If you can answer these questions, you will answer your question.


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## chrishawn (Jan 22, 2012)

First off thanks Butcher
That is thanks for putting me back in the right frame of mind. Since I went panning I got that gold fever and may have rushed things.
?1=Yes the dirt i panned had pickers & flakes[which I recovered on site]
?2=I am a newbe to panning and pretty sure between pyrite and gold
?3=I was able to smash my gold and yes i removed almost all large pebbles there is still some 1/8" diameter pebbles and all black sand, it all weights about 1/4 pound[that i prossesed in hcl-cl]
?4= I have no idea if there is other materials in this sand
?5= I screwed up and did this without having made any stanious and did not test which I know is the golden rule.
I guess my ? is there other material that will drop with smb that may be in my dirt.


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## butcher (Jan 23, 2012)

First after panning you should not have any pebbles or sand, even if you can barely see the gold (very tiny pieces) a few flakes of black sand and all of your gold is all that should be left in your pan, any thing more and your not finished panning your gold, the gold when dry can be placed on glass and the black sand blow away using air from your mouth.

After panning down to most of the heaviest stuff (black sand and gold, you can pan using a big tub of water, or bucket, this way anything you pour out of your pan into the tub can be re-panned if you accidently dumped some gold,

If you had some 1/8” gravel and quite a bit of black, or other rocks or sands, you may have not of leached much gold into your solution, what can happen is there can be a lot of iron in the dirt and black sands, your leach can dissolve some of the gold and then the iron also, and the iron in solution may push the gold back out of solution (did you save the sands or powders that did not dissolve? they may have your gold, I do not know).

Well it sound like it is time to get out that stannous chloride, and start testing.


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## chrishawn (Jan 23, 2012)

Thanks Butcher
I did save the material and stanious is cooking up.
Thanks for your help
One more ? can microscopic gold be in black sand becouse there is some thing dropping out of solution and it def. looks like gold?


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## butcher (Jan 28, 2012)

Yes very fine gold can be in with the black sands. and many believe gold can be locked up in them, in a few places around the world, also PGM can be found with them, also these sands are usually Iron materials (magnetite Fe2O3, and hematite Fe3O4, oxides of iron) and so there is also a possibility of iron sulfides (fools gold), but determining the gold from Iron sulfides should be easy.


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## shaftsinkerawc (Jan 29, 2012)

Something I need to research a little more in my area is there's a reference to Rare Earth Elements (Alanite), which is supposed to look like black sands. Anyway, main point is if you're working a regular area with lots of black sands it is probably worth having an assay done on them to verify what's in them.


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## Traveller11 (Feb 19, 2012)

Question: I can never keep this straight. Is SMB sodium metabisulphate or sodium metabisulphite?

Also, the one time I tried the HCL/CL leach on an iron rich concentrate, the solution first turned a golden brown colour, supposedly indicative of auric (gold) chloride but, as it ran out of steam, it changed to a bright yellow colour, supposedly indicative of only iron in solution.

Is there any way to make this leach work in an iron rich concentrate, other than totally removing the iron?

Bob


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## butcher (Feb 19, 2012)

Bob
SMB is sodium metabisulfite.

Many times a leach will give colors, and sometimes the colors can be clues of values in solution, but you cannot count on colors, many times they will just fool you as many metals can color solution, testing solutions will be a better indicator if solution hold value.

HCl will leach most types of iron (iron hydroxide's is hard to get into solution), the iron needs leached out before gold will stay in solution, Iron is higher in the electromotive series, so it replaces gold from the chloride solution, the HCL/Bleach is not a selective leach.


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## Traveller11 (Feb 21, 2012)

Thanks for the advice. I was thinking of using N52 rare earth magnets to remove the iron sands but it may be simpler to use hydrochloric acid, as you suggest. Hopefully, on small volumes, the cost of HCl can be kept to a profitable level.

I know that the HCl/NaOCl process gives off chlorine gas and I have ordered a full face respirator with chlorine filters. I also read somewhere that adding SMB to the pregnant solution will give off harmful gases but the article didn't say what they were.

Is this true? If so, what are the gases given off?


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## Traveller11 (Feb 24, 2012)

I just thought of another question.

If I used HCl to remove the iron sands (this would be on a small test scale, say in a test tube or small pyrex container) and then used the HCl/ NaOCl system to dissolve the gold in the material, could I test this solution with stannous chloride for the presence of gold, before I went ahead on a much larger batch?

The reason I want to test a small batch on site is this. Although it is well established, through assays, that the deposit I am going after is quite rich in -200 mesh gold, being on an ocean beach, it is quite variable with some deposits being rich in gold, others not, and no logical explanation for the difference.

Also, if a person carefully weighed a sample prior to removing iron and leaching, could this process be used to assay that sample? The reason I ask is the closest place to get assays done is the other end of the province and the lab there has recently raised the price of a gold assay to just over $60. If I could assay it myself, even if it was a slightly rough assay, it would save money and the burden of packing home worthless sand from a very remote location.


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## butcher (Mar 10, 2012)

here is some information on a field test for sulfide ore.

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=37&t=12422&start=80


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## Finn from Ecuador (Oct 18, 2015)

This was very good. I am positive about that these questions about black sands will just keep coming. This thread with the link to the other Butcher's answear should be read by every placer miner who comes to ask anything about black sands. Pitty that there is no black sands mentioned in a headline, this might be a difficult to find.

Salud

Finn


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