# I need help to refining gold



## Luca.83r (Jun 2, 2022)

Hello everybody. I apologize if you have surely already talked about the subject over and over again but I can't find a post that gives me the answers I'm looking for. I am a jeweler and have tried several times to get pure gold with AR from 18kt gold jewelry but with poor results, sometimes losing a lot of gold. as I said I would like to use both yellow and white 18 kt gold to obtain pure gold without loss of material. I had followed the classic patterns of AR, ice and then SMB. I tried to use both whole objects and sheets of a few mm thick. what am I wrong? is it necessary, using 18 kt gold, to quarter the gold? I'm here to ask for your help. thank you and sorry for my school english


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## FrugalRefiner (Jun 2, 2022)

Start with the book in my signature line below. It was written for jewelers who wanted to refine their own scrap.

Depending on the alloy you start with, you may need to inquart.

You say that you have lost gold. Remember that you never really lose gold unless you throw it away. It's there somewhere, either in the solutions or the undissolved material. You'll need to give us more details about your process for us to help figure out what you've done wrong.

Dave


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## Luca.83r (Jun 2, 2022)

thanks for now.
I will definitely read your book! as I said I use jewelry and jewelry parts in 18kt yellow or white gold, I can't say exactly the composition of the alloy. 
the procedure I used was: create a 2mm thick sheet, put it in the container, add 1 part of nitric acid and 3 parts of hydrochloric acid, heat, when almost all the material was dissolved (I had some silver-colored residues at times) I filtered , I rinsed the filter, I added ice, I added SMB, I eliminated the excess liquid and I heated the gold dust until all the liquid part was eliminated. Then I melted.
unfortunately, I am talking about 1 year ago, I threw out all the excess liquid


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## FrugalRefiner (Jun 2, 2022)

I expect the missing gold was in the material that did not dissolve since you said "almost all the material was dissolved". We inquart gold alloys because silver in the alloy can cause problems. When it exceeds around 10% it can form an impenetrable crust of silver chloride. There can be undissolved gold alloy within that crust.

Before you threw the excess liquid away, did you test it with stannous chloride?

Dave


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## nickvc (Jun 2, 2022)

Most 18k alloys have low silver content , but white alloys can have palladium , so going straight to AR should work but you need to dissolve all the metal . Once you have precipitated your gold do a stannous test on the remaining solution for palladium , as you are in italy I think your alloys will be spot on so you shouldn’t have any losses .


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## orvi (Jun 2, 2022)

If you use 3:1 premixed AR, you are probably using excess of nitric. And that is a problem, when you do not eliminate it before. 

You need to add de-noxing step before gold precipitation with SMB. Hoke in book used old fashioned but bulletproof evaporation technique. But this is lengthy and very hard on equipment, as lots of acid vapor goes to the fume hood.
Now, we use sulfamic acid to accomplish this. You add sulfamic acid to at least 75°C hot solution very slowly and observe the fizzing - fizzing means you have excess nitric acid in solution. Add slow, or it will foam over. Use at least 3 times bigger beaker than needed - to be sure that it wont foam over. As it stop fizzing by last addition, let it heat for 15 minutes at same temperature and then add another bit of sulfamic acid. If it fizz, add until it stops. If it does not fizz after that 15 minute heating, you are done and you can let it cool down and proceed with filtration and SMB gold drop.

There was excellent thread where Harold and I think GSP (??) exchanged their overwhelming experience on refining karat gold to 99,9+. But unfortunately, I cannot find it. Maybe someone help to give a link to this.


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## 4metals (Jun 2, 2022)

More on inquartation when to use and when not to.


I started with a small 10K necklace. I got a bit ahead of myself, not remembering it has to be 6K for inquarting to work. So, direct to nitric, not much reaction, as what should have been expected. Filtered off nitric solution, positive for silver, go figure. So the rest in hot AR, good results...




goldrefiningforum.com


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## Luca.83r (Jun 2, 2022)

FrugalRefiner said:


> I expect the missing gold was in the material that did not dissolve since you said "almost all the material was dissolved". We inquart gold alloys because silver in the alloy can cause problems. When it exceeds around 10% it can form an impenetrable crust of silver chloride. There can be undissolved gold alloy within that crust.
> 
> Before you threw the excess liquid away, did you test it with stannous chloride?
> 
> Dave


no, before I was not aware of the stannous chloride test and this was definitely my huge mistake. So do you think I shouldn't quarter gold?


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## Luca.83r (Jun 2, 2022)

orvi said:


> If you use 3:1 premixed AR, you are probably using excess of nitric. And that is a problem, when you do not eliminate it before.
> 
> You need to add de-noxing step before gold precipitation with SMB. Hoke in book used old fashioned but bulletproof evaporation technique. But this is lengthy and very hard on equipment, as lots of acid vapor goes to the fume hood.
> Now, we use sulfamic acid to accomplish this. You add sulfamic acid to at least 75°C hot solution very slowly and observe the fizzing - fizzing means you have excess nitric acid in solution. Add slow, or it will foam over. Use at least 3 times bigger beaker than needed - to be sure that it wont foam over. As it stop fizzing by last addition, let it heat for 15 minutes at same temperature and then add another bit of sulfamic acid. If it fizz, add until it stops. If it does not fizz after that 15 minute heating, you are done and you can let it cool down and proceed with filtration and SMB gold drop.
> ...


Thank you, i will try


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## 4metals (Jun 2, 2022)

What do you plan on. using the gold for? Are you a jeweler and intending to make it into new jewelry? 
If that is the case, the easiest path is to inquart with silver. The gold never dissolves and you can clean it up to 99.5 purity with nitric parting. Unless the gold pieces you process have platinum findings which will contaminate the gold, you can safely assume the contaminants in your semi refined gold are copper and silver. Adding additional silver and copper to make your desired karat alloy will allow you to recycle the gold back to jewelry easily. 
A plus is you can re-use the same silver over and over and silver dissolves in nitric acid efficiently so there is less waste.


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## Luca.83r (Jun 3, 2022)

4metals said:


> What do you plan on. using the gold for? Are you a jeweler and intending to make it into new jewelry?
> If that is the case, the easiest path is to inquart with silver. The gold never dissolves and you can clean it up to 99.5 purity with nitric parting. Unless the gold pieces you process have platinum findings which will contaminate the gold, you can safely assume the contaminants in your semi refined gold are copper and silver. Adding additional silver and copper to make your desired karat alloy will allow you to recycle the gold back to jewelry easily.
> A plus is you can re-use the same silver over and over and silver dissolves in nitric acid efficiently so there is less waste.


no, I buy and sell, I don't create jewels and I don't repair them. I need pure gold to exchange for new jewelry from the retailer.


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## orvi (Jun 3, 2022)

Luca.83r said:


> no, I buy and sell, I don't create jewels and I don't repair them. I need pure gold to exchange for new jewelry from the retailer.


In the start of the thread you stated that you are a jeweller, now that you do not create or repair jewellery. I do not understand, but it does not change anything in the refining issue.

Define pure gold. How pure you need it ? 99% ? 99.9 % ? There are much simpler methods for lower purity gold - like 4metals said, simple inquartation+nitric leach can give you 995 gold. If you take this 995 gold and refine one more time with AR/SMB, you can easily get 99,9+% gold. But it is an extra step need to be done. You can go to 99.9% also by just dissolving the 18k feed in AR and then deNOxing and precipitating with SMB - altough it is sometimes tedious, when you have Ag-rich alloys (silver chloride blocking access of acid to gold).


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## Luca.83r (Jun 3, 2022)

orvi said:


> In the start of the thread you stated that you are a jeweller, now that you do not create or repair jewellery. I do not understand, but it does not change anything in the refining issue.
> 
> Define pure gold. How pure you need it ? 99% ? 99.9 % ? There are much simpler methods for lower purity gold - like 4metals said, simple inquartation+nitric leach can give you 995 gold. If you take this 995 gold and refine one more time with AR/SMB, you can easily get 99,9+% gold. But it is an extra step need to be done. You can go to 99.9% also by just dissolving the 18k feed in AR and then deNOxing and precipitating with SMB - altough it is sometimes tedious, when you have Ag-rich alloys (silver chloride blocking access of acid to gold).


Orvy I am a jeweler, I buy and resell jewels, I don't do repairs. I use a laboratory for these things. I need to get 99% pure gold to give to my dealer in exchange for new jewelry. so, reading what you wrote to me, I will try again with AR. how can i deNOxing easily and effectively? With sulfamic acid?


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## orvi (Jun 3, 2022)

Yes sulfamic acid will do the trick, I wrote how to do it in the reply above.


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## 4metals (Jun 3, 2022)

Luca.83r said:


> Orvy I am a jeweler, I buy and resell jewels, I don't do repairs. I use a laboratory for these things. I need to get 99% pure gold to give to my dealer in exchange for new jewelry. so, reading what you wrote to me, I will try again with AR. how can i deNOxing easily and effectively? With sulfamic acid?


A lot of us chemistry nerds here on the forum really enjoy the chemistry and all of the different forms of metal recovery. And then there are those who are in if for the business. I guess you are in it for the business Luca. So why are you choosing to watch your gold disappear and use chemistry to bring it back? You have already seen that it may not always come back if you do something wrong. 

That’s why when guys are in it like you are may be better off watching everything else but the gold disappear. That is what inquarting and parting can do for you. Dissolve the base metals and silver and keep the gold in sight. Plus you recover the silver all from one place and recycle it over and over. And since you only need 99% purity it is totally do-able. 

Inquarting won’t work for everybody but for you it can and it can do it effectively using only one chemical, nitric acid.


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## Luca.83r (Jun 3, 2022)

4metals said:


> A lot of us chemistry nerds here on the forum really enjoy the chemistry and all of the different forms of metal recovery. And then there are those who are in if for the business. I guess you are in it for the business Luca. So why are you choosing to watch your gold disappear and use chemistry to bring it back? You have already seen that it may not always come back if you do something wrong.
> 
> That’s why when guys are in it like you are may be better off watching everything else but the gold disappear. That is what inquarting and parting can do for you. Dissolve the base metals and silver and keep the gold in sight. Plus you recover the silver all from one place and recycle it over and over. And since you only need 99% purity it is totally do-able.
> 
> Inquarting won’t work for everybody but for you it can and it can do it effectively using only one chemical, nitric acid.


yes, you're right, I do it for business, but chemistry has always fascinated me and it's nice to see gold disappear and then return it (if everything works without problems!). so I would like to learn the method perfectly and will read the book very carefully. So you say that by quartering gold and using only nitric acid I can get 99% pure gold?


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## 4metals (Jun 3, 2022)

Luca.83r said:


> So you say that by quartering gold and using only nitric acid I can get 99% pure gold?


For sure. You need to melt your scrap and the required quantity of silver together so it is homogeneous and pour it into water to get small shots to dissolve. Then add a mixture of 2 parts distilled water and 1 part nitric acid with heat to dissolve out the silver and base metals. When the reaction is complete the gold will remain. Filter it, rinse it, and again add nitric and distilled water but this time 1:1, acid to water. Heat it again and allow the acid to dissolve out any remaining base metals. If the shot you made was large, you may need to use a glass rod to break up the chunks to help the dissolve. (This is in both the first and second dissolve). Filter it again, rinse and dry the gold and then melt it for sale. 

This should meet your 99% Gold requirement. The second acid is just to enhance and get any remaining base metals or silver to dissolve out of the gold. It will not be exhausted and can be diluted a little bit to make it 2:1 and reused for your next lot. The first acid will contain most of the silver so you can cement it on copper to recover it for re-use. 
The beauty of this method is it will work on a few ounces of gold or many ounces. This is why it has appeal with small jewelers 
reworking gold scrap or, like you, reselling it. 

If your fascination with the chemistry still beckons, the end result of the semi-refining by inquarting is a great feedstock for an aqua regia refine.


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## Luca.83r (Jun 3, 2022)

4metals said:


> For sure. You need to melt your scrap and the required quantity of silver together so it is homogeneous and pour it into water to get small shots to dissolve. Then add a mixture of 2 parts distilled water and 1 part nitric acid with heat to dissolve out the silver and base metals. When the reaction is complete the gold will remain. Filter it, rinse it, and again add nitric and distilled water but this time 1:1, acid to water. Heat it again and allow the acid to dissolve out any remaining base metals. If the shot you made was large, you may need to use a glass rod to break up the chunks to help the dissolve. (This is in both the first and second dissolve). Filter it again, rinse and dry the gold and then melt it for sale.
> 
> This should meet your 99% Gold requirement. The second acid is just to enhance and get any remaining base metals or silver to dissolve out of the gold. It will not be exhausted and can be diluted a little bit to make it 2:1 and reused for your next lot. The first acid will contain most of the silver so you can cement it on copper to recover it for re-use.
> The beauty of this method is it will work on a few ounces of gold or many ounces. This is why it has appeal with small jewelers
> ...


Ok Thank you.
where can i find the correct amount of silver to use to quarter 18kt gold?


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## 4metals (Jun 3, 2022)

The goal with inquartation is to make one quarter of the alloy gold and the balance silver. For small lots, under 5 ounces of alloy total, all you need do is figure out how much gold is in the lot. Whatever that number is, add 3 times the expected gold quantity as silver.

Some will say you need to take into account the base metals and silver already in the alloy and while it cannot hurt to figure that out and adjust your silver addition accordingly but for small lots like you will likely process, just add 3 times the expected gold weight as silver. 

Take care to remove any platinum findings like prongs that hold stones because the platinum will remain with the gold and lower the purity. 

Melt the alloy and the silver together and stir it well and pour it into water to make it into grain for digestion. 

That’s all that is involved. There are plenty of threads about recovering the dissolved silver for re-use on the forum. 

Good luck.


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## Luca.83r (Jun 4, 2022)

4metals said:


> The goal with inquartation is to make one quarter of the alloy gold and the balance silver. For small lots, under 5 ounces of alloy total, all you need do is figure out how much gold is in the lot. Whatever that number is, add 3 times the expected gold quantity as silver.
> 
> Some will say you need to take into account the base metals and silver already in the alloy and while it cannot hurt to figure that out and adjust your silver addition accordingly but for small lots like you will likely process, just add 3 times the expected gold weight as silver.
> 
> ...


So if i have 100gr of 18kt gold i use 300gr of silver?


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## 4metals (Jun 4, 2022)

18 karat gold is only 75% gold so you use (100 x .75) x 3 = 225 grams of silver. 
You could use 300 grams of silver but that is more than necessary and will produce more waste and more silver to recycle than necessary.


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## cejohnsonsr1 (Jun 5, 2022)

Luca.83r said:


> So if i have 100gr of 18kt gold i use 300gr of silver?


No. That would be too much silver. 18kt is 75% gold by weight so 25 gr is already not gold. So you figure out what 75gr is as 25% of the whole. The difference, minus the 25gr you already have is how much silver you need to add. (75x4=300 300-75=225 225-25=200) So you need to add 200gr of silver to inquart.


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## Shark (Jun 5, 2022)

100•.75=75
75 is gold or 1/4 of total material.

75•3=225
225 is 3/4 of the total amount of material to add to jewelry.

225(75%)+75(25%)=300 or 100% of material to be ran in nitric.


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## Shark (Jun 5, 2022)

To little silver and the nitric may not reach it where it can be dissolved out of the gold. To much and you risk having very fine gold that can make it harder to deal with unless you go to AR with it. Both can be dealt with with out a lot of problems but they do change how it can be handled somewhat.


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## 4metals (Jun 5, 2022)

cejohnsonsr1 said:


> No. That would be too much silver. 18kt is 75% gold by weight so 25 gr is already not gold. So you figure out what 75gr is as 25% of the whole. The difference, minus the 25gr you already have is how much silver you need to add. (75x4=300 300-75=225 225-25=200) So you need to add 200gr of silver to inquart.


I did expect someone to actually bring this up!


4metals said:


> Some will say you need to take into account the base metals and silver already in the alloy and while it cannot hurt to figure that out and adjust your silver addition accordingly but for small lots like you will likely process, just add 3 times the expected gold weight as silver.


The formulation I gave was the keep it simple formula which will work very well. You could do the calculation as @cejohnsr1 did and save a little nitric acid. When someone is having trouble as the OP was and starts a thread with a title "I need help refining gold" I take it that they are having trouble and I try to break it down to the lowest common denominator so when they try it, they are most likely to be successful. Nothing worse or more demoralizing than trouble with your first lot. Thus my simple calculation;


4metals said:


> 18 karat gold is only 75% gold so you use (100 x .75) x 3 = 225 grams of silver.


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## Shark (Jun 5, 2022)

4metals said:


> I did expect someone to actually bring this up!
> 
> The formulation I gave was the keep it simple formula which will work very well. You could do the calculation as @cejohnsr1 did and save a little nitric acid. When someone is having trouble as the OP was and starts a thread with a title "I need help refining gold" I take it that they are having trouble and I try to break it down to the lowest common denominator so when they try it, they are most likely to be successful. Nothing worse or more demoralizing than trouble with your first lot. Thus my simple calculation;


Given the two different results, could the 75 gram difference be considered a safety margin between to much and to little to maintain a relatively chunky gold after the nitric bath?


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## 4metals (Jun 5, 2022)

Shark said:


> Given the two different results, could the 75 gram difference be considered a safety margin between to much and to little to maintain a relatively chunky gold after the nitric bath?


When fire assaying, adding 3 times the sample weight of Silver produces a powder not unlike coffee grains. The dorè beads created by cupellation are completely penetrated by the nitric acid. An assay technique used widely in Europe uses less Silver additions and the resulting Dorè bead is rolled flat and folded before nitric acid treatment. The rolled coronet does not crumble and remains a gold ribbon after the Silver is parted out. 

If you are inquarting and do not wish to roll out every piece of shot the ability of the nitric parting acid to penetrate the shot will be less and the end result less pure. 

The one argument against not rolling the dorè is the small coffee granule pieces are easily lost when transferring the gold. I have found that the gold parted with 3:1 Silver and not rolled are well behaved and easily decanted without loss. One might ask how do I know if the losses are small with the finer gold particles? Since I have used this process extensively in karat fire assays, the samples are run in duplicate or triplicate. Results for individual cups are very close indicating a good assay and also meaning no fine gold particles were lost to rinsing and decanting.


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## cejohnsonsr1 (Jun 6, 2022)

Shark said:


> 100•.75=75
> 75 is gold or 1/4 of total material.
> 
> 75•3=225
> ...


225 total. But as I pointed out, 25 gr is already present in the 18kt gold. So you only need to add 200 to arrive at 225. Adding 225 brings the total to 250.


Shark said:


> Given the two different results, could the 75 gram difference be considered a safety margin between to much and to little to maintain a relatively chunky gold after the nitric bath?


What remains after precipitation will be the same regardless. The difference here is how much nitric you have to consume to remove the silver and base metals, the time it takes to remove it and the amount of waste you will generate. The least amount of each is always going to be best. And the calculations I provided previously are not complex or difficult. One possible exception might be if you have an ongoing silver process alongside your gold. Then a little extra silver won’t matter quite so much, but it still won’t help your gold process in the least. The point being that whatever you add to the gold has to be completely removed. And too much just makes it take longer and cost more to arrive at the same place.


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## Shark (Jun 6, 2022)

I see now. I did not account for the original 25% from the jewelry. Once this is accounted for (by subtracting it from the 225 silver) the numbers would be 200. On the scale I work this is not a problem or even enough to make much difference in time or cost. But I can see where it could be huge on a commercial scale.


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## 4metals (Jun 6, 2022)

In a large operation, where an instrument lab or fire assay lab or even an XRF is available it is worth differentiating what the additional components of the 18K alloy are and adjusting the formula accordingly. Remember the vastly different quantities of nitric acid consumed by copper than silver? Without knowing how much of that 25% is actually silver can change the calculus and result in incomplete digestion. 

These are some very old formulations, all for 18 karat gold, resulting in different colors.

Red (deep Pink)
75 parts Gold
25 parts Copper

Pale Red
75 parts Gold
8 parts Silver
17 parts Copper

Grass (deep) Green
75 parts Gold
25 parts Silver

Deep Pink
75 parts Gold
25 parts Copper

Yellow Green
75 parts Gold
12.5 parts Silver
12.5 parts Cadmium

Blue / Grey
75 parts Gold
25 parts iron

White
75 parts Gold 
25 parts Platinum or Palladium

Bright Yellow
75 parts Gold
19.5 parts Silver
5.5 parts Copper

Deep Yellow
75 parts Gold
12.5 parts Silver
12.5 parts Copper

Purple
75 parts Gold
23 parts Aluminum
0.5 parts Tin
1.5 parts Thorium

This is why I value simplicity when getting one's feet wet in refining.


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## orvi (Jun 7, 2022)

In refining, most of the times you can get approximate measures of how much of certain chemical would you need. But it is much better to observe the situation and adjust as you go.

Nitric in inquarting is a typical example. You can do 2 things - observe copper or silver in solution. Aim of the inquartation is to get rid of all silver and base metals from the inquarted gold. Luckily, silver is relatively easy to detect in solution. All you need is solution of salt in water. Draw a small sample (like 0,5ml) with pipette to the separate container or small beaker. Then drop one or two drops of salt solution into. If silver is present, white precipitate of AgCl would be formed. This test is very sensitive for silver.

Also, vast majority of gold alloys contain copper. You can visualy observe the presence of copper in nitric solution by it´s colour. If the nitric acid boil is no longer getting even the slightest blue hint, you are close to the end. If you draw like 0,5 ml of the liquid, and add like 1 ml of ammonia to it, in the presence of copper deep blue colour of amino-Cu complex will develop. This is much more accurate than judging plain, untreated sample of solution.


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## Luca.83r (Jun 7, 2022)

4metals said:


> 18 karat gold is only 75% gold so you use (100 x .75) x 3 = 225 grams of silver.
> You could use 300 grams of silver but that is more than necessary and will produce more waste and more silver to recycle than necessary.


Last question (maybe). When you say silver do you mean 925 silver? Because i have a lot of 800. Can i use it?


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## Yggdrasil (Jun 7, 2022)

You can, what you want is to get the gold content down to 6 karat which is 25%.
More silver less copper means less nitric needed, but that's it.


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## billgold (Jun 11, 2022)

4metals said:


> In a large operation, where an instrument lab or fire assay lab or even an XRF is available it is worth differentiating what the additional components of the 18K alloy are and adjusting the formula accordingly. Remember the vastly different quantities of nitric acid consumed by copper than silver? Without knowing how much of that 25% is actually silver can change the calculus and result in incomplete digestion.
> 
> These are some very old formulations, all for 18 karat gold, resulting in different colors.
> 
> ...


I think you have a typo for the bright gold formulation. I would guess that it should be 19.5 parts silver.


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## 4metals (Jun 11, 2022)

billgold said:


> I think you have a typo for the bright gold formulation. I would guess that it should be 19.5 parts silver.


You are correct, I edited it to 19.5%

Those are very old formulations. Nobody’s using Cadmium anymore. Or thorium! Can’t say I ever heard of thorium in an alloy before but the alloy did have a purple tint to it. I was at an old estate auction in Scotland years back and I bid on and won a collection from a jeweler with a sample of every alloy they make all in vials and there was a sheet with all the percentages. It was pretty neat to see all the colors of alloys they made. I didn’t pay a lot and it yielded about 4 oz of gold if I remember right. Kick myself for not taking a photo of them.


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## Luca.83r (Jul 16, 2022)

Here We go again.
I quartered gold with silver and tried to refine it further in AR. At the end I added sulfamic acid for Denox, I filtered, I added ice and SMB, I tested with stannous and negative for gold. I filtered the gold. I started with 64 g of 18 kt gold and now I got 34 g of gold. where did I go wrong and how can I recover the "lost" gold? I kept the filtered liquid.
Who Can help me?


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## Yggdrasil (Jul 16, 2022)

Luca.83r said:


> Here We go again.
> I quartered gold with silver and tried to refine it further in AR. At the end I added sulfamic acid for Denox, I filtered, I added ice and SMB, I tested with stannous and negative for gold. I filtered the gold. I started with 64 g of 18 kt gold and now I got 34 g of gold. where did I go wrong and how can I recover the "lost" gold? I kept the filtered liquid.
> Who Can help me?


The reason for quartering is to get the Gold content low enough so Nitric can dissolve the Silver.
AR is definitively wrong at this stage.


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## FrugalRefiner (Jul 16, 2022)

As Yggdrasil said, going to AR after inquarting is wrong.

When you dissolved your gold and filtered, were there any pieces of stuff that did not fully dissolve?

Dave


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## 4metals (Jul 16, 2022)

From the library, there is this thread about inquarting. 

Gold Nugget 1.495 OZT - No Aqua Regia 99.67% fine

And another telling you when to use it and when not to. Find it from the library index thread. 

LIBRARY INDEX THREAD

Start with just inquarting and raising the purity to >99% by nitric parting and when you feel confident, move on to aqua regia refining. All the time keeping in mind they are very different processes.


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## Luca.83r (Jul 17, 2022)

no sorry, I didn't make myself clear. i inquarting gold, i added nitric acid and water and repeated the process until i had a colorless liquid, then i went to AR


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## Luca.83r (Jul 17, 2022)

FrugalRefiner said:


> As Yggdrasil said, going to AR after inquarting is wrong.
> 
> When you dissolved your gold and filtered, were there any pieces of stuff that did not fully dissolve?
> 
> Dave


no, all completely dissolved, clean filter. now after precipitating with SMB and filtering I have a completely transparent liquid. Stannous test negative


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## Yggdrasil (Jul 17, 2022)

Luca.83r said:


> no sorry, I didn't make myself clear. i inquarting gold, i added nitric acid and water and repeated the process until i had a colorless liquid, then i went to AR


anything left in there after?
White or yellow?


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## Luca.83r (Jul 17, 2022)

Yggdrasil said:


> anything left in there after?
> White or yellow?


Nothing. Only transparent liquid like pure water.


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## Luca.83r (Jul 17, 2022)

the only thing I can think of is that I lost some gold dust when I melted it with propane, but I can't have lost 10 gr. 
 I am very sad, not for losing money but for still doing something wrong. From that transparent liquid I can not recover anything in your opinion?


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## Yggdrasil (Jul 17, 2022)

Luca.83r said:


> Nothing. Only transparent liquid like pure water.


Let me rephrase:

Was there any solids left after the Gold was dissolved in AR?

Is it white or yellow Gold?

How much did the Gold weigh after the Nitric treatment?

How much Nitric did you use in the AR?


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## Luca.83r (Jul 17, 2022)

Yggdrasil said:


> Let me rephrase:
> 
> Was there any solids left after the Gold was dissolved in AR?
> 
> ...


no, no solid after AR.
it was just yellow gold. 
I didn't weigh the gold after the nitric acid treatment, 
I used the same glass and went straight to AR. I added nitric acid a little at a time until all the gold was dissolved


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## Yggdrasil (Jul 17, 2022)

Ok.
It may have been less karat in the Gold than you believed.
It fits nicely with 9 karat, maybe plated for the colour.
As long as you don’t know how much you had left after parting the Silver we can’t say.


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## 4metals (Jul 17, 2022)

Essentially the inquarting and parting of the silver to leave just gold is a crude fire assay. We do not know how you identified the karat of the material you processed, either by markings on the individual pieces or testing on a stone, but neither is as accurate as weighing the actual gold remaining after inquarting and parting. 

Given your descriptions of complete dissolution and clear solutions after rinsing the only logical explanation remaining is the gold was not there to start with. I agree with Yggdrasil's assumption. 

A few minutes spent drying the gold after parting so it can be weighed would be time well spent.


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## Luca.83r (Jul 17, 2022)

4metals said:


> Essentially the inquarting and parting of the silver to leave just gold is a crude fire assay. We do not know how you identified the karat of the material you processed, either by markings on the individual pieces or testing on a stone, but neither is as accurate as weighing the actual gold remaining after inquarting and parting.
> 
> Given your descriptions of complete dissolution and clear solutions after rinsing the only logical explanation remaining is the gold was not there to start with. I agree with Yggdrasil's assumption.
> 
> A few minutes spent drying the gold after parting so it can be weighed would be time well spent.


I checked the 750 hallmark and tested on stone, from there I went to add silver by calculating pure gold x 3.


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## Yggdrasil (Jul 17, 2022)

Luca.83r said:


> I checked the 750 hallmark and tested on stone, from there I went to add silver by calculating pure gold x 3.


It was just an Idea.
Next time I advice you to check.


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## Luca.83r (Jul 17, 2022)

Yggdrasil said:


> It was just an Idea.
> Next time I advice you to check.


I will definitely do it. next week I try with a little material, 30 gr 18kt and I will mark all the exact weights


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