# AR or HCL + Chlorine?



## Paige (Apr 18, 2007)

If you wanted to digest 2 oz of 14kt jewellry, which would work best?

Steves video was minute amounts of gold. What would be needed to increase volume.

Also, can't you get chlorine from a swimming pool place and run a tube into your HCL to supply more chlorine than bleach?

Paige


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## Harold_V (Apr 18, 2007)

Having refined karat gold for years, almost exclusively, I found no good reason to depart from inquartation and then AR. It's fast, clean and effective. Unless you enjoy re-inventing the wheel, I see no good reason to process by other means, especially in small volumes. 

Were you involved in huge volumes, I might enjoy a different stance. I recall reading that 10,000 ounces of gold could be brought fine in something like 24 hours by the Miller process. That method isn't exactly tuned to the home refiner, however. 

Harold


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## lazersteve (Apr 18, 2007)

Paige,

AR is the way to go for karat jewelry. The HCl-Cl method was demonstrated as an alternative to the hazards of AR. It is useful on gold that is in fine flake, foil, or powdered form. The speed of attack of the HCl-Cl mixture is 10 times slower than AR. On finely divided gold this is not really an issue, but for solid larger masses of gold where the surface area is not large realtive to the overall mass of the gold, the method is very slow. The video was intended to demonstrate alternative means of dissolving gold which has a large surface area, such as foils and powders. The HCl-Cl method has an advantage that it doesn't require nitric acid and is made from easily obtainable chemicals.

Steve


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## goldsilverpro (Apr 18, 2007)

Steve,

Have you ever tried the HCl/Cl2 on karat gold? I've noticed that you've mentioned the 10X speed difference between it and AR a couple of times. Did you obtain this 10X figure from doing karat gold or from doing powder and foil? I bring this up because, unless I'm greatly mistaken, HCl/Cl2 will never dissolve karat gold. The silver content is just too high and acts as a barrier. Even with the much more powerful aqua regia, some pieces won't dissolve. I just hate for people to misunderstand and waste time trying to dissolve karat gold with HCl/Cl2.

Here's a trick. If you *only* have 10KT gold, or below (a lot of Mexican gold is 6KT or 8KT, or worse), you can dissolve everything but the gold with hot 60/40 to 70/30 (nitric/distilled water) nitric acid, without inquarting. It may take 3 or 4 hours and the solution should be just below boiling. It won't work on anything higher than 10KT. This is especially interesting on 10KT class rings. When everything is gone but the gold, the class ring will maintain it's shape and you'll still be able to read the writing on it. The difference is that it will be totally composed of brown gold powder. When you touch it with a stir rod, it will collapse. You can tell when all is finished by mashing everything with a stir rod. If all the pieces collapse, they are finished. If all is not finished, add a little straight nitric and keep driving it hard. If it still won't finish, you have some things that are higher than 10KT. I can't ever remember this method failing.

After leaching the 10KT and removing the nitric solution, with a few rinses, you dissolve the remaining gold powder with a very small amount of AR. You could, probably, use HCl/Cl2 or HCl/H2O2 to dissolve the gold powder instead of using AR.


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## lazersteve (Apr 18, 2007)

Chris,

Sorry for the confusion. 
DO NOT USE HCl-Cl to attempt to dissolve Karat Gold. When referencing the 10x faster figure I mean the AR dissolves nearly pure gold, gold powder from inquartations, and gold foils 10x faster than HCl-Cl. The HCl-Cl has the same problems with karated gold above 9kt that AR does, the silver will shield the gold from going into solution. The key to using the less reactive solvents is the surface area of the gold. Here are some scenarios where the slower reacting solvents will do the job of dissolving the gold:

1) After you have inquarted gold with a base metal into a fine powder,

2) After you have processed several pounds of gold plated scrap in the cell and have a fine black powder,

3) After you have used a crock pot to strip the base metals from fingers or pins and have a 'mash' of gold plating foils,

In all of the above cases AR will do the job 10x faster or better depending on which solvent you choose. If you melt the product of any of the above processes into a gold button, the slower reacting solvents will work, but at a MUCH slower rate than the AR will work. The key to effectively using the slower solvents is the surface area of the gold. The main benefits of the other solvents are safety and avaliblity of yhe chemicals.

I hope this clears up my previuos posts.

Steve


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