# Making Auric Chloride at Home: Questions and Comments



## lazersteve (Apr 8, 2007)

Here's where you can comment on my latest tutorial. The tutorial is here:

http://goldrefiningforum.com/phpBB3/viewtopic.php?p=1876

Steve


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## sandhog (Apr 8, 2007)

Great job Steve,

If I understand you correctly, after dissolution you would then move right to Sodium Metabisulfite. Also, is the amount of AU that can be in solution about the same as aqua regia.

-Bill


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## Fever (Apr 8, 2007)

Nice vid, Steve....

Why stopper the test tubes? I noticed you mentioned that there was pressure building up, and you released it periodically, but this can be very dangerous. Were you concerned about heat retention?

Fever


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## lazersteve (Apr 8, 2007)

The amount of auric chloride which can dissolve in an aqueous solution is due to it's solubility of 68 gms/ 100 mL. This varies by temperature , hotter aqueous solutions can dissolve more auric chloride.


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## lazersteve (Apr 8, 2007)

Fever,

I'm glad you liked it.

The gas produced was very minimal due to the small scale of the reaction. This was by design for the purpose of filming the video. The toxicity of the gas was the main reason for stoppering. Chlorine is dangerous, but in my opinion not as much so as NOx gases produced by the AR method. As long as you work the reaction as I have demonstrated and provide for good ventilation, this reaction will scale up easily. I feel a crockpot would be a realistic working scale for most hobbyist. Adding more muratic and bleach as required to push the reaction to completion. If silver is in the gold a salt may form. 

The amount of heat used was very minimal, just enough to keep the reaction going. If you notice I was holding the vials with my hand ( no tool ), this is how you can be sure there was not that much heat involved. 

As sandhog mentioned above you go straight to the bisulfite after filtering if necessary.

Steve


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## catfish (Apr 8, 2007)

Hi Steve

Great video and good idea. 

Question 1:

Could a person use this Aqua Regia to refine both ceramic and fiber CPU chips. Would there be a reaction to the fiber?

Question 2:

Do you have a formula developed as far as the ratio of both Clorox and Muriatic acid?

Question 3:

What would be a good starting point of total AR should be used to refine about 20 ceramic CPU chips at one time with the heat sink removed?

Question 4:

About what temperature would you recommend that the AR be heated: (Naturaly I would do this out doors.) With a crock pot.

Question 5:

Would I also need to neutralize the spent AR before precipitating the gold?

I beleive in the tutoral, you mentioned that the gold would be precipitated as usual with Sodium met.

Steve, I only refine gold plated items only, such as Chips and pins. I use AR on just about every thing except large plated items and then I use my electrolysis cell then. This apears to be some what safer than Nitric acid (sodium nitrate) and muriatic acid, and much less expensive. 


Again many thanks for you untiring efforts and contribution to this forum inorder that we all may benefit from your extensive knowledge and experience.

Thanks Again

Catfish


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## lazersteve (Apr 8, 2007)

Catfish,

I'm glad I'm getting such a good response to this tutorial, something told me it would be big when the light went off in my head.

I'll try to answer your questions in the order they were asked:

1 ) You are referring to this reaction as AR (aqua regia).. it is not. This reaction should work on any gold which is in a foil or a finely divide state. The ceramic cpus would need to be ground to a very fine consistency to get at the interior gold wires. The solution would need to be filtered afterward. The cpu surface and pins plate would be attacked by the mixture in the video, but the base metals would also be attacked. The foil I used in the video actually was removed from a 486 cpu plate. What are commonly referred to as 'fiber cpus' are mostly epoxy layers with fiber sheets in between. They don't crush very well at all and are, in my opinion, best processed with acid peroxide.

2)The ratios are in fact a combination of two separate reactions the first is known as the HCl-Cl method has been around for quite some time. The method calls for concentrated HCl saturated with chlorine gas. This is the next best mixture to AR for attacking gold. Unfortunately chlorine gas is dangerous to produce and hard to handle for the hobbyist. I was going to show the forum an easy technique for generating the gas and using it in this reaction. That's when I had this brainstorm while formulating the procedure. This procedure is much safer than generating the gas and saturating the HCl with the gas. The original method also required adding chlorine as the reaction progresses which only added complexity.

The second part of the reaction is not as well known as the former but is even older. It's called the Chlorine Water method. This method generates the above required oxidizing chlorine 'in situ' (in the reaction vessel) via the equation:

NaOCl + 2HCl --> *Cl2* + H2O + NaCl 

and this chlorine gas is then reacting with the additional HCl via

-OCl + -Cl + (2H3O+) --> Cl2 + 3H2O
-OCl + H2O <--> HOCl + -OH

Normally this requires diluting the reaction with excess water to hold the chlorine which is produced by the reaction. 

The produced Cl2 in conjunction with additional HCl is the driving force of this newly revealed combination reaction of my own creation. 

In essence we have produced Chlorine Water in HCl acid without resorting to the additional chlorine generating equipment. The beauty of this is that the solution is not diluted as in the normal chlorine water reactions (due to the low solubility of Cl2 in water). We use the chlorine ions as they are formed to dissolve the gold. 

For the above mentioned reasons I have designed the experiment to run at a pace set by the addition of the NaOCl. By controlling the amount of added bleach we can in effect control the rate of chlorine production 'in situ'. If the heating is closely controlled we can avoid driving the chlorine out of the solution so that it can react with the gold instead. The trick is to add small amounts of the bleach slowly so that only enough chlorine is produced to dissolve the gold. When the solution stops absorbing gold when gently heated just add another small dose of bleach. Remember the chlorine from the bleach will end up in tied to the gold as AuCl initially and eventually as AuCl3. From this we can calculate that it will take 3 moles of NaoCl per mole of Au. As for the HCl it is the initiating molecule and is regenerated as the reaction proceeds. As I mentioned in a previous post the solubilty of Gold Chloride is 68 gm /100 mL in cold aqueous solution, this is a good starting point for your calculation of HCl (31.5% HCl / 68.5% H20). If you have a large amount of foreign material in the reaction you will need more to compensate for the increase volume of the reactants.





3) a. Do the math on estimated amounts of gold to be absorbed based on expected yield. 
b. Crush the material to be processed as fine as possible. 
c. Setup the reaction vessel in a well ventilated area.
d. Add the calculated amount of muratic from the previous paragraph.
e. Slowly add a very small amount of bleach and observe the reaction rate.
f. Gently heat mixture
g. Slowly add small amounts of bleach until all gold is absorbed.
NOTE: Adding bleach to HOT acid is very dangerous the solution can increase 10 fold or more in volume from the gases generated if added too fast.* You will lose your gold if the reaction boils over*. It is wise to cool the mixture to room temperature before adding additional bleach. If adding bleach doesn't cause additional absorption, reduce heat, let cool to room temperature, add a small quantity of HCl and reheat.
h. Cool and Filter
i. Precipitate with usual methods.





4) Again, this is not AR. The reaction should be run at the least possible heat (40C or less typically ) to keep it going. Overheating drives off the required chlorine gas and extends the reaction time. 

5) Again this is not AR, no need to neutralize, go straight to SMB. Dilution may help precipitation if solution is very concentrated.

WOW !! That was a long post, but I made it through. :lol: Now everyone take a look over it and give me your opinions and suggestions.

Steve


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## Noxx (Apr 9, 2007)

This is a really good tutorial ! I never eared of the technique before... Maybe I'll give it a try soon 
Thanks Steve


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## Paige (Apr 16, 2007)

Why can't I view the tutorial?

Paige


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## lazersteve (Apr 16, 2007)

I've noticed some activity on my site that is coming from an unknown location so I'm working on removing the suspected leech. I've temporarily enabled access again. Check it out now and let us know what you think. 

Steve


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## ChucknC (Apr 16, 2007)

How would you go about disposing of the stripped solution? Does this work on any of the PGM's?

Chuck


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## lazersteve (Apr 16, 2007)

The barren solution should be disposed of as with any other stripped solution. Test for valuables, drop the base metals, filter, neutralize, and dispose. I use aluminum foil to drop, I think it was Harold that pointed out that iron or steel also works and is cheaper.

It should work on Pd foil or powder. I doubt it would be effective on the higher PGM's, but I don't know for sure. Anybody know?

Steve


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## P_CARROLL (May 8, 2007)

How about usnig a higher concentration of sodium hypochlorate than in bleach. would that speed the reaction as higher concentrations can be purchased at a chemical store or pool store.


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## lazersteve (May 9, 2007)

P_Carrol,

The higher concentration bleach isn't _necessary_ because the goal is to produce just enough Cl2 gas *in the solution* to dissolve the foil or powder, the liquid will only hold so much Cl2 and the rest just goes into the air. The low concentration allows the Cl2 produced to stay in the solution and attack the gold instead of going into the air. A second problem with the higher concentration stuff is that the reaction would be more violent when it comes into contact with the acid, making the whole reaction harder to control.

I guess you could go with the higher concentration bleach just use proportionally less of it. The benefit is that the volume of the solution will be less with the higher concentration bleach. Just remember that the solution won't hold all the chlorine gas produced by mixing the acid and bleach and the excess gas will therefore need to be dealt with. Also be extra safe working with the more reactive ingredients.

Steve


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## goldsilverpro (May 9, 2007)

What about starting with a full shot of bleach and then drip it in or add an occasional shot?

In practice, the gas dissolved in the solution tends to always decrease and maybe replenishing would help.


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## lazersteve (May 9, 2007)

Chris,

That may solve the excess chlorine problem, but it also brings up another possibility, start with the bleach in the reaction vessel and add the acid dropwise. I'm not sure if the reaction equilibrium would be greatly affected by the excess hypochlorite as opposed to excess chlorine when starting with the acid. It may be worth testing out. If I recall the equation favors chlorine production with excess acid.

Steve


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## goldsilverpro (May 9, 2007)

Steve,

Starting with bleach and adding HCl is very interesting. 

I reread your post on the first page. It seems like the best speed is in keeping sufficient Cl2 concentration. If the loss is due to heat generation, the vessel could sit in a little ice. I would think the ideal way would be to drip the bleach in, with stirring, and monitor the temperature. Stirring replaces the spent chemicals, with fresh, at the surface of the gold and makes things go faster. I wonder how an aquarium air pump would work, as a stirrer? It might reduce the Cl2, however. The extra oxygen might help, though. Have you tried HCl, H2O2, and bleach?

Every reaction is a time, temperature, and concentration thing. Speed within Safety is always the goal.

Are you adding any water? Is the ratio of HCl/bleach about 1/1? It might help to prevent foamovers by adding a little anti-foam agent. They sell it where they rent out carpet cleaners. A drop might be enough.


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## lazersteve (May 9, 2007)

Chris,

The air bubbler is going to introduce more N2 than O2 which may, under these conditions ultimately become a diluted form of AR :!: :?: 

Very interesting indeed.

I've yet to try adding any H2O2.

It looks like I have some more experiments to run when I get home tonight.

Steve


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## goldsilverpro (May 9, 2007)

Nitrogen is inert. I still think that the 3% H2O2 is holding you back in these experiments. I've used 30-35% H2O2 all my life to jack up dissolving reactions. I've used it with all acids, many alkalis, and cyanide. They all go faster. But, one secret of speed in most reactions is to keep the water out. Three percent H2O2 is 97% water. Even 12% from a beauty supply would help greatly. I have tried 3% on many things without much luck.


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## Charlena (Jun 27, 2007)

I can't find out where to get the tin powder!
what did I miss? lmao

Thanks Steve great job!


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## aflacglobal (Jun 27, 2007)

It's me, Ernest T.

That's right here i go again. Tiatomic Oxygen.

I still think that the 3% H2O2 is holding you back in these experiments. I've used 30-35% H2O2 all my life to jack up dissolving reactions. I've used it with all acids, many alkalis, and cyanide. They all go faster. But, one secret of speed in most reactions is to keep the water out. 

O3 ? could it be introduced Thru a aeration stone into the acid. No water.
And you can control the addition pretty specific. Might solve the heat problem ?

Just remember that the solution won't hold all the chlorine gas produced by mixing the acid and bleach and the excess gas will therefore need to be dealt with

Could it also be used to convert the excess chlorine into some less harmless gas or liquid ?

How much futher outside the box can i get. lol

Ralph


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## lazersteve (Jun 27, 2007)

Charlena said:


> I can't find out where to get the tin powder!



Lead free solder at the hardware store (95% tin / 5% antimony).

or 


I bought the tin powder from ebayer "finepowder".

Steve


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## lazersteve (Jun 27, 2007)

Ralph said:


> I still think that the 3% H2O2 is holding you back in these experiments.



The reaction *does not* call for peroxide as demonstrated. The addition of peroxide was discussed, but I haven't tried it myself.

It's been a while since I developed this method and I've successfully scaled it up to do larger quantities of gold. The largest amount of gold I've dissolved in one batch using this method was 11 grams. Heat was not a problem, nor were excess off gases. The trick is adding the Clorox in small portions with stirring. Heating *isn't* required for foils, but helps a little with gold powders

Steve


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## scavenger (Jun 28, 2007)

I found some Tin Oxide powder at a jewelers equipment store. Do u think it would be suitable for making test solution? Cheers Dave.


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## Charlena (Jun 29, 2007)

lazersteve said:


> Lead free solder at the hardware store (95% tin / 5% antimony).



Would any of these be that type?
I can't find on them the ingredients. :?


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## lazersteve (Jun 29, 2007)

Try searching the manufacturers web sites for MSDS information.

Steve


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## Charlena (Jun 29, 2007)

same packaging at fry's but they put that info on the price tag! Much more helpful than lowes!
So yes i got it....YEAHHHHH
works awesome!
is there a suggested formula on this stuff? ratio wise?
and shelf life? capped or uncapped?
Thanks hun :arrow: Steve :!:


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## postmako (Jul 8, 2007)

scavenger said:
 

> I found some Tin Oxide powder at a jewelers equipment store. Do u think it would be suitable for making test solution? Cheers Dave.



You would first need to convert it from SnO to Sn and here is a patent regarding this. I think you will agree that it is easier to buy solder.
http://www.freepatentsonline.com/5342590.html

Cheers,
Kory


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## Charlena (Jul 8, 2007)

> I think you will agree that it is easier to buy solder.




Do you know what the exact formula is on the solder method? how much do i use per how much hcl?
Thanks
Char


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## lazersteve (Jul 8, 2007)

The ratio is not critical. 

Add 20 mL HCl and clip in 4" of lead free solder to a pyrex beaker. 
Heat until the solder begins to dissolve. 
Let the reaction proceed with gentle heating if required.
 The bulk of the solder will dissolve leaving a fine black powder (antimony powder). 
Pour off the solution into a CLEAN 30 mL dropper bottle (amber is better). 
Do not pour any of the black powder into the dropper bottle. 
Test the stannous chloride solution with a know auric chloride solution. 
Remains active about 1 week. 
Test before each use with known auric chloride solution.
Refresh activity with additional solder, HCL and heating as needed.

Steve


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## Charlena (Jul 8, 2007)

You rock!


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## goldsilverpro (Jul 8, 2007)

Although it doesn't make much difference, I've always preferred using stannous chloride. I use a clean eyedropper (drug store) and put 2 drops of the solution to be tested on a piece of filter paper. I then get a few crystals on the tip of my knife and put them onto the drops. Then I add a drop or two of water. The water re-moistens it and makes it work faster. Notice the color. Gold is purple or nearly black. Palladium is yellow-brown. Platinum is yellow. The only other thing, that I know of that will produce a color, besides some of the other platinum group metals, is cobalt. Sometimes, it produces a light blue.

The type filter paper is important. The drops of solution are absorbed by the paper and the colors spread out. The various precious metals spread out to different distances. You can tell what, and how much (if you're good at it) of each of the metals you have by noticing the color and intensity of each color ring. You want a fairly hard paper that won't allow the colors to spread too quickly. There is an common analysis method called paper chromatography. You simply hang a strip of filter paper (sometimes, treated) down into a small container of the liquid sample. The solution climbs up the paper and separates into it's individual chemicals. Interesting stuff. By running and comparing standards, you could get a pretty good idea of what and how much is in the solution.


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## aflacglobal (Jul 8, 2007)

Interesting indeed. When i grow up i want to be like you GSP. lol

The solution climbs up the paper and separates into it's individual chemicals

Hey! A new idea :idea: Seperation by the wicking method. :wink:


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## gold-seeker (Jan 19, 2008)

New here, hi everyone, been watching the forum for a while, question i have is what all base metals does the Auric Chloride desolve? This reason im asking is that if i put mixed small sand, gold and whatever else may be in their, what all gets desolved? Thanks


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## ChucknC (Jan 19, 2008)

Ralph,
It's called thin layer Chromatography. A fairly old method of analysis of an ore.


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## lazersteve (Jan 19, 2008)

Seeker said:


> New here, hi everyone, been watching the forum for a while, question i have is what all base metals does the Auric Chloride desolve? This reason im asking is that if i put mixed small sand, gold and whatever else may be in their, what all gets desolved? Thanks



Gold-Seeker,

When using HCl and Clorox to dissolve your gold, the base metals should have previously been removed by another means. If not they tend to dissolve into your HCl-Cl first which could prevent your gold from dissolving at all. 

Auric Chloride is the dissolved form of gold in solution and does not dissolve base metals. The HCl-Cl does all the dissolving.

Best practice is to keep all base metals out of the HCl-Cl reaction as much as possible.

Steve


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## gold-seeker (Jan 19, 2008)

Thanks Steve and Others, if i have already dissolve everything, (then i have a mess) can it be seperated then the gold dropped!
Thanks



lazersteve said:


> Seeker said:
> 
> 
> > New here, hi everyone, been watching the forum for a while, question i have is what all base metals does the Auric Chloride desolve? This reason im asking is that if i put mixed small sand, gold and whatever else may be in their, what all gets desolved? Thanks
> ...


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## Harold_V (Jan 19, 2008)

If everything is in solution, there's nothing wrong with precipitating the gold via normal procedures. It will come down quite dirty due to drag down, and won't wash nearly as well as if it had been precipitated from a cleaner solution, but doing so is better than starting over. If you choose to go this route, figure on re-refining the gold to bring it pure. It likely will benefit by doing so. 

If you choose to precipitate everything in solution so you can start over, you'd do that by inserting a piece of aluminum or steel (or zinc in any configuration, including flour), which would reduce all the metals in the form of a sludge, at which time you could then dissolve the base metals without dissolving the precious metals. 

This process is a little more involved than I've just mentioned, so don't jump in with both feet unless you're prepared to jump through a hoop or two. It's important that you eliminate any chlorides in the collected sludge, so you can dissolve the base metals without the values going in to solution as well. It's also a bit of trouble removing values from the surfaces of the remaining aluminum or steel, unless you have an abundance of HCl in the solution. In that case. it would dissolve the surface enough to liberate all traces. 

There's one more way you can precipitate the gold, but it's hard to clean up the deposits for the same reason, above. You can use a piece of copper, which will selectively precipitate the gold and any platinum metals you may have dissolved. All the base metals would stay in solution. The problem is cleaning the copper of values when they have all been precipitated. Much easier if you're working with a nitrate solution in this case. 

Harold


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## The Refiner49er (Feb 14, 2008)

> Harold wrote:
> There's one more way you can precipitate the gold, but it's hard to clean up the deposits for the same reason, above. You can use a piece of copper, which will selectively precipitate the gold and any platinum metals you may have dissolved. All the base metals would stay in solution. The problem is cleaning the copper of values when they have all been precipitated. Much easier if you're working with a nitrate solution in this case.



I want to read this back to ensure I saavy this separation process. If you have a solution of mixed metals, you can precipitate the gold and PGMs onto copper (a thin copper sheet for instance), and then dissolve the Cu with nitric or AP, and filter the Au and Pt solids from the solution. 
It seems like this is a fairly direct method of losing the base metals from a dirty solution. Did I get this right? I hope so.

One of these days I'm gonna have to learn to read english. (swahili is my native language) :lol:


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## Harold_V (Feb 14, 2008)

honemaster said:


> If you have a solution of mixed metals, you can precipitate the gold and PGMs onto copper (a thin copper sheet for instance), and then dissolve the Cu with nitric or AP, and filter the Au and Pt solids from the solution.
> It seems like this is a fairly direct method of losing the base metals from a dirty solution. Did I get this right? I hope so.



Yes, you got it right. Copper will precipitate all of the precious metals you're likely to encounter. The only fly in the ointment is if you have palladium in solution. It will re-dissolve along with the copper if you clean up with nitric acid. If so, you would simply clean the copper by washing with tap water, and leave traces on the plate. You'd collect them the next time you used the copper for the same purpose. It, eventually, would be totally consumed. You have a little value locked up, but it's not lost. 

Harold


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## jacknicholson (Aug 2, 2011)

Can't get to the video link, it seems to be broken. Is the video posted anywhere else?
Thanks,


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## jimdoc (Aug 2, 2011)

Go to Steve's website and look for it there.
The link is in his signature, in the post with the broken link.

Jim


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## Dude4ever (May 6, 2012)

How do you know that chlorine is out of solution and that it is safe to drop with SMB?


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## Geo (May 6, 2012)

Dude4ever said:


> How do you know that chlorine is out of solution and that it is safe to drop with SMB?



chlorine will evaporate from solution at room temperature on its own with no further action needed than to be left alone.depending on how much bleach you added to the solution 12-24 hours is all thats needed. you can stir the solution before adding water, if the solution bubbles or fizzes, it still has free chlorine. if you shake the solution till all the bubbles rise to the top and no more bubbles form in a few minutes then the chlorine is evaporated.


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## saadat68 (Dec 17, 2018)

Hi
If I want dissolve some gold powders or gold foiles with hcl/cl method but *without heating* solution
How much time I must wait between adding shots
(I know with heating we must wait 1 to 5 minutes and then add another shot of chlorex) 
Thanks


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## goldscraphobby (Dec 18, 2018)

I never heat, I use a strong bottle (usually a cleaned simply orange bottle) add the gold & HCl, then I put in the chlorine and close it tight. Shake it up and let it sit. Every once and awhile shake it real good to mix it around. Not in a rush so I let it take its time.
Just don't put too much to exceed the pressure of the bottle. Never had an issue and reduces the amount needed.


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## saadat68 (Dec 18, 2018)

goldscraphobby said:


> I never heat, I use a strong bottle (usually a cleaned simply orange bottle) add the gold & HCl, then I put in the chlorine and close it tight. Shake it up and let it sit. Every once and awhile shake it real good to mix it around. Not in a rush so I let it take its time.
> Just don't put too much to exceed the pressure of the bottle. Never had an issue and reduces the amount needed.



Thank you
How much time do you wait usually then add another shot of chlorex?


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## goldscraphobby (Dec 19, 2018)

It depends on how patient you are and how much gold. Sometimes I just add once and keep shaking it over a fews days. till its all disolved or its used up. If its doesn't seem to react Then add a little more.


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## saadat68 (Dec 19, 2018)

Thanks
Wow few days!
My thought was we can wait one or two hours


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## anachronism (Dec 19, 2018)

saadat68 said:


> Hi
> If I want dissolve some gold powders or gold foiles with hcl/cl method but *without heating* solution
> How much time I must wait between adding shots
> (I know with heating we must wait 1 to 5 minutes and then add another shot of chlorex)
> Thanks



The simple answer is "until it not doing anything."


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## saadat68 (Dec 19, 2018)

anachronism said:


> saadat68 said:
> 
> 
> > Hi
> ...



Thanks
How long does it take usually for gold foils and gold powders? One or two days?


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## anachronism (Dec 19, 2018)

Sometimes it takes a few minutes. Depends how many you have and how thick they are, and how strong your solution is and how hot it is. I've never had to use it for powders. 

Give it a try - you might get some of your own answers.


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