# how reifne gold from rhodium



## maryam (Aug 25, 2012)

i want to know how we can refine gold from rhodium when we want to melt gold plated jewelry?


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## jimdoc (Aug 25, 2012)

maryam said:


> i want to know how we can refine gold from rhodium when we want to melt gold plated jewelry?



Why melt gold plated jewelry? The gold plate is on the surface. If you melt it, you make things more difficult, by then creating an alloy. Look up sulfuric cell in the search box. How much of your material do you think is rhodium plated?


Jim


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## maryam (Aug 26, 2012)

hi Jim
we are gold jewelry manufacturer that melt at least 30 kg gold rhodium plated daily and as the rhodium dosnt separate from gold during melting process it becomes a large amount of rhodium in gold and decrease the purity of it .
thanks


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## jimdoc (Aug 26, 2012)

I can't help you, I could only wish I had a problem with too much rhodium in my gold.
There are a few members that should be able to give you some advice when they see your post.

Jim


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## maryam (Aug 26, 2012)

thanks anyway.


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## NobleMetalWorks (Aug 26, 2012)

maryam said:


> i want to know how we can refine gold from rhodium when we want to melt gold plated jewelry?



In your original post it sounds like you are asking about gold plated rhodium, but that doesn't make any sense since rhodium jewelry is very rare. So if you really are talking about gold plated jewelry, then it would also have to be rhodium treated on top of the gold plate.



> we are gold jewelry manufacturer that melt at least 30 kg gold rhodium plated daily and as the rhodium dosnt separate from gold during melting process it becomes a large amount of rhodium in gold and decrease the purity of it .



Here you mention "rhodium plated" which leads me to believe that you have gold jewelry that is rhodium plated?

If you could be more clear about what exactly is plated, and what it's plated over. Is this karat gold jewelry that is rhodium plated?

Are you talking about gold plated jewelry that is rhodium treated?

White gold plated jewelry that is rhodium treated?

Gold Karat jewelry that is rhodium plated?

White gold karat jewelry that is rhodium plated?

You will have a truly difficult time if you are trying to remove rhodium from gold. However, it's far easier to remove gold from rhodium. What I mean by this is that if you digest your gold in Aqua Regia, the only metals that should not be dissolved would be rhodium. Thus you would be removing the gold from the rhodium, and the rhodium would fall as sand on the bottom. Since the amount of rhodium is so little, it would be difficult to see unless you dissolve a lot of this type of material.

The only thing that makes sense to me is that you are talking about a white gold alloy that is rhodium plated. That type of jewelry is fairly common. I believe almost all white gold sold in jewelry stores has been rhodium treated.

If you could provide more information maybe the members on the forum would be able to help you more.

Scott


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## maryam (Aug 26, 2012)

Hi Scotte 
As mentioned, we are gold jewelry maker that finish our product by white rhodium and use of 18 K (750) gold .
we usually melt second hand rhodium plated jewelry to make 750 bar and during melting process all impurity were removed except the very little rhodium that used for finishing, at the result it is not real 750 gold (although it is not shown in test of gold purity)
and when this cycle is repeated during time the amount of rhodium in gold will increase .
then we are looking for a way to remove the rhodium from 18 k gold.
i hope i explained well what i mean.

Thanks


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## butcher (Aug 26, 2012)

maryam,

Hoke's book will help give you the details to answer your question, I think you would find this book will help you in many areas of your business, as a jeweler this book could help to save you a lot of money.

The gold can be refined, during the process; rhodium could be recovered as insoluble powder.

Rhodium plate removal from jewelry (I have never tried), sounds very hard, you could try grinding it off, the concentrated sulfuric acid cell (gold stripping cell) may also work, the Rhodium plate may just stay in solution as a sulfate (just a guess here), gold would report as insoluble powder.

It sounds as though you have melted the plating with the gold into a bar, in this case you do not have rhodium plate any more, but Rh mixed in the gold as an alloy, if you sell these bars as scrap, finding a refiner who would pay you for these other metals, or you could learn to refine your gold and collect the Rhodium powders.


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## maryam (Aug 27, 2012)

in past it had not been a serious matter for us because the price of rhodium was not lower than the gold 's,
but now it is considered as impurity of gold


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## nickvc (Aug 27, 2012)

In honesty the amount of rhodium plate on jewellery is minimal and probably isn't worth recovering alone but if your alloys contain palladium or silver it might be worth the effort. Re using the white gold as is is also not advisable as the rhodium will cause problems making the material brittle and finishing very hard, the answer is to refine the metal yourselves and then re alloy your own metals saving the refiners charges and the uplift from buying alloyed material, this way you eventually recover the rhodium through the filters and the stockpot and reduce your costs by reusing your scrap gold, you can also do all your own lemels, bench sweeps, and even your polishing and floor sweeps with a little more learning.


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