# foils with one side brown



## rpg (Nov 19, 2012)

I tried to do a search on this, but is so generic that i get a ton of results and couldn't find one that mentions it. 

I have about 5 grams of gold foils with the backside brown. I'm assuming this is still copper. Should I run them through the AP again or should I just put them into the HCL/CL? Thank you in advance


----------



## ericrm (Nov 19, 2012)

just process them with your regular finger board in ap...


----------



## AndyWilliams (Nov 19, 2012)

rpg said:


> I tried to do a search on this, but is so generic that i get a ton of results and couldn't find one that mentions it.
> 
> I have about 5 grams of gold foils with the backside brown. I'm assuming this is still copper. Should I run them through the AP again or should I just put them into the HCL/CL? Thank you in advance



Just responding to test my knowledge, don't take anything I say as a guide. Smarter minds will weigh in! 

I would say that if you still have copper, don't do HCL/CL. Your copper will cement out the gold, resulting in a less than ideal process. Essentially, the copper will go into solution first, and then the gold. That would present difficulty in recovering gold, which could be in two states in your reaction vessel (in solution and as a precipitate). I would advise doing AP until you have no more reaction.


----------



## rpg (Nov 19, 2012)

that's what I thought, but just wanted to be sure. Thank you all


----------



## rpg (Nov 19, 2012)

OK, now I'm getting the foils dissolved into the AP solution, perhaps I put too much peroxide. After a few hours the solution is green yellowish and most of the foils are gone. Pretty much only have some green plastic foils left out. After filtering, is "stump out" the right approach to recover the gold? Will it give me 100% recovery or should I use some other process? TIA


----------



## eesakiwi (Nov 19, 2012)

I'm doing this right now too, brown copper backed gold fingers ripped off from a RAM stick.

I sorta went like this.
In a 125ml flask. Teaspoon of foils lightly squashed.

1. Washed the foils with HCL acid. Warm up & Pour off Hcl.

2. Added HCL & a little 33% H2O2, solution goes greenish, add low heat, reaction, copper starts to dissapear & solution gets lighter.
Adds drop of H2O2, same again. Low heat.
Again H2O2. Breakup of some gold flakes & brown copper slowly dissapearing.
--------
Once almost all of the brown has gone I'd wash it with water & dry it.
Then I'd add HCL, 1/2 volume of squashed foils, add H2O2 & let it react outside till its all in solution.
Filter it.
Add SMB & the gold should drop out as a brown powder, in theory.
----------
The two things I still don't know is.
A. how much HCL to add to the foils in the first place. The reaction dosn't seem to like having acid added to it.
Its better to start off with the right amount.
B. How much HCL exactly to add to the gold foils, I'm thinking its like 1/2 foil volumeThe reaction does little at the start, then it takes off.


----------



## butcher (Nov 19, 2012)

You first want to recover the gold, as free from other metals as much as possible, before moving on to the refining process where you dissolve the gold.

Recovery and refining these two different processes and should not be combined.

To combine or mix these two separate processes is complicating things and will cause a greater loss of values.

If you just used HCl and a little 3% H2O2 to begin with and then bubbled air from a fish tank air bubbler, you could remove copper without dissolving the gold foils.

Using strong hydrogen peroxide is just complicating the process dissolving gold with copper, this should be avoided for better results, and a cleaner gold solution when you move from recovering the gold to refining the gold, where you want to dissolve the gold with as little other metals as possible, making the refining easier, less loss of values, and better gold in the end product.


----------



## rpg (Nov 20, 2012)

Butcher, I've read in the board 2 possible solutions. One advocated by Steve calls for the use of SMB to drop the gold, and I've read your opinion against it. The other calls to add copper until gold drops out. Now, for a newbie like me, confusion reigns. What is the approach you recommend? 

In regards to the initial process, I realized what I've done once i looked at saw the foils almost gone, but at that time it was already too late, as only a few were left. I have it running now with the air bubbler plus some extra fingers hoping it will turn brown so the gold can drop out. Your guidance is appreciated. Thank you


----------



## rewalston (Nov 20, 2012)

rpg said:


> Butcher, I've read in the board 2 possible solutions. One advocated by Steve calls for the use of SMB to drop the gold, and I've read your opinion against it. The other calls to add copper until gold drops out. Now, for a newbie like me, confusion reigns. What is the approach you recommend?
> 
> In regards to the initial process, I realized what I've done once i looked at saw the foils almost gone, but at that time it was already too late, as only a few were left. I have it running now with the air bubbler plus some extra fingers hoping it will turn brown so the gold can drop out. Your guidance is appreciated. Thank you



AP as others have said is a recovery process. As more copper is added to the AP and dissolves it will drop the gold out as a black powder. By using a bubbler you don't need to add more H2O2, as an excess of H2O2 will cause gold to be dissolved into solution. This dissolved gold is precipitated out as more copper is dissolved into solution. This copper can be from fingers or even dropping a piece of copper into the AP. After all that is what we do with the stockpot when we are processing our wastes. The copper will drop anything that is in your AP. So when you see the black powder you can decant that and do your normal washes before you go into the refining stage of the game.

Rusty


----------



## rpg (Nov 20, 2012)

thank you rusty. I'll do that


----------



## butcher (Nov 20, 2012)

rpg,

I am not against using SMB to precipitate gold; I use it often to precipitate gold from a clean gold solution.
But there are times when its use would create more problems than it would solve.

Much depends on what you are dealing with whether I would use copper as elemental metal to replace gold from solution (as a recovery method), or use SMB to precipitate gold from solution as a refining method, or use some other reagent like ferrous sulfate to precipitate gold from solution.

Copper will recover gold where there is a problem, like too much nitric, or a solution loaded with base metals where a chemical reagent like SMB would possibly not work or would just be more problems.

SMB would work better for refining where you have eliminated the base metals and have fairly pure gold in solution, and have also removed the oxidizers like free nitric acid or chlorine from bleach, or chlorine and oxygen from use of concentrated hydrogen peroxide.

There are several reagents that will precipitate gold from solution, and they each have there place in refining, I cannot think of any I am against using, but also believe there are places where one should be used rather than the other depending on circumstances, I also do not believe me or Laser Steve would disagree of when one should, or should not be used, other than maybe personal preference or some other reason like choice at that time. 

You have chosen a good process to proceed with your problem, the copper in the added foils will precipitate your gold from solution as a fine powder, as the copper II chloride leaches copper from the added foils, just be careful to let this powder settle well when decanting, and washing your gold.


----------



## butcher (Nov 20, 2012)

By adding more foils to this batch you will tame the copper II chloride ability to dissolve gold, recover your gold from solution, and keep your solution in a state that it can be reused.

If you would have used SMB at this point you would have changed the chemistry of your solution, to where it is no longer a copper II chloride solution, but a chloride and a sulfate solution, where it would not be able to be reused, and also if you used SMB here you would have precipitated copper with your gold as very fine powders, just complicating things for you in the long run.


----------



## rpg (Nov 20, 2012)

this is only a 100 ml batch that i set up just to clean the copper out of the gold. I'm adding some copper wire and let the air bubbler run all day today until the solution turns brown. 
Is it safe to assume that on the regular AP finger process if you overdue the peroxide some of the gold will end up in the solution? If the only thing required to dissolve the copper is oxygen that is initially supplied by peroxide, would it be safe to assume the HCL with a air bubbler would do the job? TIA


----------



## steyr223 (Nov 20, 2012)

"If you overdue the peroxide some gold will go
Into solution "

Yes. Just wait and the process of dissolving the copper
from your boards will drive the gold back out
unless you used way way to much

I will take a stab at this
please correct me if I'm wrong

Hcl and the bubbler alone I do not think would
begin the process of dissolving copper which
Is what we need to make CuCl2..
I believe you need peroxide 3% to kickstart the reaction in dissolving the copper 
so the air bubbler can continue the dissolution of
Copper
hope this helps
Steyr223 rob


----------



## rpg (Nov 21, 2012)

I had the AP running all day with a couple of copper wires to solution exaust (really dark brown and no more signs of yellow). It is still wet, but it has a dark brown color, kind of like wet copper. Is this what is expected? TIA


----------



## butcher (Nov 21, 2012)

Once (chlorine gas and oxygen if concentrated H2O2 were used), or once oxygen is depleted the solution will darken form bright clear green to a very dark green, the copper in solution can turn brown if much Copper I Chloride is developing in solution and will begin to form white copper I chloride salts falling to the bottom of the vessel with any gold powders.

A little more HCl and water will dissolve the copper I chloride white salts and form more copper II chloride in solution, adding a splash of 3% H2O2 or bubbling plenty of oxygen from air will give back the bright green color, leaving gold as flakes or very fine powder in the bottom of vessel, (note bubbling action can move the fine gold powders around in solution)

Laser Steve's web site has an excellent document on this subject, any one using the copper II chloride leach (acid peroxide) should study it for an understanding of how it works, and how to use it to your benefit


----------



## rpg (Nov 21, 2012)

what I add dropping was mostly copper. I'll run the bubbler on the new solution (that has some water on it used to clean the filter). I re-filtered the solution and got some, not much, black powder. Now what should I do with the brown powder? put it back into a AP? TIA


----------



## butcher (Nov 21, 2012)

If it were just a tiny bit I would save them in a small jar, until you collect an appreciable amount to process.

If this came from electronic scrap and tin and lead is a possibility I incinerate the powders and wash the powders in a boil of HCl and boiling water before proceeding.

The black powder gold can be cleaned up some using Harold's gold washing technique (see getting your gold pure and shiny found in the help needed section.

This will remove a lot of impurity, then the gold can be refined, put into solution and precipitated, HCl and sodium hypochlorite (bleach) is an easier method to deal with, the gold from this can be washed again using Harold’s method, and may need to be refined a second time with a final washing before melting'

If it is only a small amount of gold, it is better to save it up, as there will be some gold lose in the processes (but not truly lost as it is recovered later with proper procedures and use of stock pot),

The black gold has a lot of base metals to remove so the actual gold per weight will be less after these base metals are removed.


----------



## rpg (Nov 21, 2012)

this came all from fingers, although some solder is always possible. Initially I had +/- 5 grams of foils. In the current solution (that has a mix of water from washing the filters) I can see a color separation. At the top green tea color, at the 1/3 bottom yellowish green. I think my gold is still there.


----------



## butcher (Nov 21, 2012)

A stannous chloride test on a Qtip can tell you if gold is in solution.


----------



## rpg (Nov 21, 2012)

dropped everything back into the solution is starting from scratch. Added more HCL and a tiny bit of peroxide and a few more fingers. Running with the air bubbler now. I'm sure the gold is in the powder I recovered. So my assumption is if I run it again in AP the copper will go back into the solution and the gold powder will be left in the bottom. Any gold that will get dissolved will be dropped by saturation, so I'll continue to add fingers until solution is saturated again. As I was not planning in refining gold until spring (I'm in new england and snow is coming) I did not order Tin drops until yesterday. Sometime next week I should be able to test for gold in the solution. I'll keep you up to date of my chemical on the job learning (I'm a software guy with minimal chemical knowledge) TIA


----------



## butcher (Nov 21, 2012)

That sounds like a plan.

It will also give so time to get a little more knowledge under your hat, while the copper dissolve from the pins and leaving the gold in the bottom of your bucket.

Winter time is a good time to make Nitric acid, Sit by the warm fire with a good bookreading Hoke's, and a good hot drink.


----------



## steyr223 (Nov 22, 2012)

Sit by a warm fire 
Reading Hoke's
A hot drink


You just had to mention nitric acid :mrgreen: 
You gave me the chills


----------



## eesakiwi (Nov 23, 2012)

butcher said:


> You first want to recover the gold, as free from other metals as much as possible, before moving on to the refining process where you dissolve the gold.
> 
> If you just used HCl and a little 3% H2O2 to begin with and then bubbled air from a fish tank air bubbler, you could remove copper without dissolving the gold foils.
> 
> Using strong hydrogen peroxide is just complicating the process dissolving gold with copper, this should be avoided for better results, and a cleaner gold solution when you move from recovering the gold to refining the gold, where you want to dissolve the gold with as little other metals as possible, making the refining easier, less loss of values, and better gold in the end product.



Thankyou for this information. I now relise that added concentrated H2O2 will 'overconcentrate' in the acid & dissolve the gold.
& that I should have not used 30% in the first place......

I understand how the gold will 'plate out' back onto the remaining copper & thats why the reaction is hard to start sometimes, like when I pour the liquid out, clean the still copper plated foils & add new HCL/h2O2.
It makes sense to use the air bubbler, theres no way it can 'over concentrate' the HCL acid, which would dissolve the gold..


----------



## nickvc (Nov 23, 2012)

eesakiwi said:


> butcher said:
> 
> 
> > You first want to recover the gold, as free from other metals as much as possible, before moving on to the refining process where you dissolve the gold.
> ...




I fear your still not understanding what's dissolving your gold. The hydrochloric won't dissolve gold under normal conditions but add an oxidiser like nitric, chlorine or peroxide and it will and readily.


----------

