Can anyone tell me why i'm not even recovering the amount of pure silver I added to inquart gold?? For example today I refined about 40g of 10k gold, I added 27g of silver to lower gold % to 25%. I then disolved base metal in 50/50 nitric, putted aside the gold powder, dropped silver chloride by adding HCL. Took the silver chloride aded 2 part water for 1 part HCL and added AL to convert to elemental. Decanted, dried. Then I heated the silver in a silica melting dish, after about 30sec heating with my oxy-acet torch huge quantity of smoke begin being produced. The powder reduced and some kind of strange liquid formed in the botom of my dish. This famous liquid is kind of exploding when dropped into cold water, anybody got any idea what this could be?!??!. The resulting silver is, as usual quite pure and clean but I lose much of it somewhere or somehow and cant figure it out. With this lot I was suposed to yield my inital 27g + about 15g from the 10k alloy, instead I only recovered about 19g ?!?!??!?! can anybody help me out?? I'm tired of loosing silver each time I inquart. Or maybe someone could teach me another way to process other than dropping chloride and then converting it... and I dont like using coper to recover silver it's too long and time consuming compared to the chloride thing.
Losing silver with inquartation....
- Thread starter elfixx
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I'll give it a stab, but you might want to wait for Harold or someone else much more knowledgeable.
Chapter VIII, Pg. 78: after the chloride has been thouroughly washed, cover it w/ diluted sulphuric acid (1 part to 15-20 parts water, acid into the water slowly and always stirring.) Cover the chloride well & add Zinc shavings or foil stirring often to make the metallic silver.
Later in the chapter, it states you can also use Al. Seems this might actually be cheaper & faster, but, like I said...you'd probably be better served waiting to hear from one of the other guys.
Cheers,
John
Chapter VIII, Pg. 78: after the chloride has been thouroughly washed, cover it w/ diluted sulphuric acid (1 part to 15-20 parts water, acid into the water slowly and always stirring.) Cover the chloride well & add Zinc shavings or foil stirring often to make the metallic silver.
Later in the chapter, it states you can also use Al. Seems this might actually be cheaper & faster, but, like I said...you'd probably be better served waiting to hear from one of the other guys.
Cheers,
John
Elfixx,
Using a torch to melt silver is not a good idea. Your torch temperatures far exceed that required for silver to melt. This excess temperature promotes vaporization of the silver and it's compounds. A light grayish silver color on the edges of the dish is a strong indication that the metal was volatilized.
Your extra silver likely went up in smoke. Silver chloride vapors are very bad for your health.
The smoke and liquid are an indication of silver chloride being present, also some aluminum compounds may have been present if your chloride was not thoroughly washed (10-15 hot washes). Washes should be alternated between water and dilute acid (HCl). The resulting metal powder should be pressed free of all liquid and allowed to dry.
When done converting silver chloride be sure you test a small sample of the converted metal with ammonium hydroxide before melting. If the filtered ammonium hydroxide wash solution clouds up or produces any precipitate when HCl is added, conversion is incomplete.
Steve
Using a torch to melt silver is not a good idea. Your torch temperatures far exceed that required for silver to melt. This excess temperature promotes vaporization of the silver and it's compounds. A light grayish silver color on the edges of the dish is a strong indication that the metal was volatilized.
elfixx said:
Your extra silver likely went up in smoke. Silver chloride vapors are very bad for your health.
The smoke and liquid are an indication of silver chloride being present, also some aluminum compounds may have been present if your chloride was not thoroughly washed (10-15 hot washes). Washes should be alternated between water and dilute acid (HCl). The resulting metal powder should be pressed free of all liquid and allowed to dry.
When done converting silver chloride be sure you test a small sample of the converted metal with ammonium hydroxide before melting. If the filtered ammonium hydroxide wash solution clouds up or produces any precipitate when HCl is added, conversion is incomplete.
Steve
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You did not convert the silver chloride completely. Of that there is no question. If you'll add some soda ash and reheat, you'll recover that which was not lost in vapors.elfixx said:
I question your choice of recovering your silver. Why aren't you using copper? Working with silver chloride, unless you have no other options, is a very poor choice.
There's nothing wrong with using a torch for melting silver---I did it without issues for more than 20 years, all the while having no less than two melting furnaces at my disposal. They're a waste of time unless you have large volumes to melt. You can have a lot torch melted and in process faster than you can heat a furnace. Key to success is to use a torch that is sized to the operation. My choice was a large Hoke torch, with a tip that was akin to the typical rosebud. To avoid losing metals, simply don't overheat them. It's easy to do with a torch, but not necessary to achieve acceptable melting.
Harold
Why do you think there are 15 grams of silver in 40 grams of 10K? Only in the case of green karat gold will it contain that much. Forty grams of yellow or white will usually contain about 3 or 4 grams of silver.
Harold,
I reread his post and it still sounds to me like he added 27 grams (the correct amount) for inquaration and assumed there was an additional 15 grams of silver contained in the original 40 grams of 10K (37.5% silver). It sounds like he was looking for a total of 42 grams of silver. I was saying he should have had no more than a total of 30-31 grams, unless the 10K was green gold.
I may be having a senior moment. Maybe, elfixx can straighten me out.
Also, in your capable hands, torch melting of silver works fine. You know, however, how easy it is for a novice to overheat the silver and lose it, especially with inadequate equipment. This vaporized silver is very dangerous to breathe. The silver chloride present, due to inadequate conversion, vaporizes at a lower temperature and is especially dangerous to breathe. No matter what method is used for conversion, it is very difficult to convert 100% of the AgCl. Unless everything goes perfectly, there will be at least a trace of AgCl mixed with the silver. So, unless one has the right melting equipment plus experience plus an excellent fume hood, I surely would not recommend the torch melting of silver.
I reread his post and it still sounds to me like he added 27 grams (the correct amount) for inquaration and assumed there was an additional 15 grams of silver contained in the original 40 grams of 10K (37.5% silver). It sounds like he was looking for a total of 42 grams of silver. I was saying he should have had no more than a total of 30-31 grams, unless the 10K was green gold.
I may be having a senior moment. Maybe, elfixx can straighten me out.
Also, in your capable hands, torch melting of silver works fine. You know, however, how easy it is for a novice to overheat the silver and lose it, especially with inadequate equipment. This vaporized silver is very dangerous to breathe. The silver chloride present, due to inadequate conversion, vaporizes at a lower temperature and is especially dangerous to breathe. No matter what method is used for conversion, it is very difficult to convert 100% of the AgCl. Unless everything goes perfectly, there will be at least a trace of AgCl mixed with the silver. So, unless one has the right melting equipment plus experience plus an excellent fume hood, I surely would not recommend the torch melting of silver.
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Yep, I agree. I should have read the entire post a second time.goldsilverpro said:
Everything he described sounds to me like silver chloride being left behind instead of being converted. He should have recovered no less than the added silver, assuming it was added as pure, not an alloy (coin or sterling).
By the way, yes, all of my silver torch melting was done in the hood. No fumes to worry about. My hood moved up to 1,000 cfm.
Harold
That's what it sounds like to me. He shouldn't have gone the silver chloride route. He should have cemented on copper. It makes it so much easier to get all the silver back.
Unless forced into producing silver chloride, never intentionally produce it. About the only example of being forced into it is when doing karat gold in aqua regia.
Juan Manuel Arcos Frank
Well-known member
I am very close to know nothing about gold,but every day I see many people refining their karat gold by the inquartation method (with copper or silver) and here is what I see:
Make the inquartation,then melt the mixure and roll the metal to a thin slab that you can cut with your own fingers,then add concentrated nitric acid to the cutted slabs and stirr occasionally until no fumes are released,pour off the liquid,wash 3 times the mud with distilled water(SOLUTION WITH SILVER) and add more concentrated nitric acid to the cutted slabs and boil the solution to dryness...then melt the brown powder to gold.
To recovery the silver in the solution just add common salt until no white clumps are formed,let settle down the white mud,wash it,then add sodium hydroxide,stirr until get a black mud and finally add common sugar and stirr until a grey/green precipitate is formed,which is the pure silver.
Nobody complains about silver lost.
I hope it helps.
Manuel
Make the inquartation,then melt the mixure and roll the metal to a thin slab that you can cut with your own fingers,then add concentrated nitric acid to the cutted slabs and stirr occasionally until no fumes are released,pour off the liquid,wash 3 times the mud with distilled water(SOLUTION WITH SILVER) and add more concentrated nitric acid to the cutted slabs and boil the solution to dryness...then melt the brown powder to gold.
To recovery the silver in the solution just add common salt until no white clumps are formed,let settle down the white mud,wash it,then add sodium hydroxide,stirr until get a black mud and finally add common sugar and stirr until a grey/green precipitate is formed,which is the pure silver.
Nobody complains about silver lost.
I hope it helps.
Manuel
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Actually, if readers have the least interest in the inquartation process, there is no better reference than Hoke's book. It spells out in adequate detail what is to be done, and how it should be done, and why!
Anyone interested in processing karat gold should read the book until it is understood well. Questions that may seem without answers now are readily addressed with ease, once you understand what she teaches. That is particularly true for folks like me, with no chemical education.
Read Hoke!
Harold
Anyone interested in processing karat gold should read the book until it is understood well. Questions that may seem without answers now are readily addressed with ease, once you understand what she teaches. That is particularly true for folks like me, with no chemical education.
Read Hoke!
Harold
I still have the same problem, this time I have been realy carefull not to over heat, I completly converted the chloride to elemental and used a lot of boric acid/borax flux. Once more some kind of strange stuff liquified in the botom of my melting dish... This difenitly is where my silver is going. I got some pic of that strange stuff.
It melt very quickly and become dark and perfectly liquid just like water, when dropped into water in makes little explosion. It has no reaction in conc. nitric and is insolube in water. I'm realy damn tired of loosing silver to this strange stuff. I can't beleve no one has even encounter this...
Hard to tell, but it looks like silver chloride to me. Most every one that converts AgCl to Ag will encounter it, sooner or latter. I know I have. Silver chloride melts at a low 851 F and becomes very fluid. Once it has been melted, it becomes much more difficult to convert.
If you're tired of losing silver, you'll need to improve your silver chloride to silver conversion skills. It's obvious that you haven't been successful at it.
Better still, don't produce silver chloride in the first place. Cement the silver out of the solution onto copper. Very simple to do, almost 100% efficient, and it always works.
Your life will be much easier if you don't have to screw around with silver chloride..
If you're tired of losing silver, you'll need to improve your silver chloride to silver conversion skills. It's obvious that you haven't been successful at it.
Better still, don't produce silver chloride in the first place. Cement the silver out of the solution onto copper. Very simple to do, almost 100% efficient, and it always works.
Your life will be much easier if you don't have to screw around with silver chloride..
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I see no mention of soda ash. Any particular reason?elfixx said:
Wise people don't keep doing the same thing over and over that has failed previously. To expect a different outcome borders on insanity! :lol:
You have been advised to abandon recovering silver as chloride, with excellent reasons why provided. If you'd like to pursue inquartation and enjoy trouble free success, you really need to start using copper to recover your silver.
Harold
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I don't advise copper wire unless you intend to re-melt the silver for use in inquartation once again.
When you use copper wire, it doesn't dissolve uniformly, so in the end you risk having small bits of copper wire mixed with the silver. If the silver is targeted for the parting cell, you tend to defeat the purpose of processing the silver in a sense, by contaminating the electrolyte prematurely. Beyond that, wire is very acceptable.
I used to melt wire or any small bits of copper and cast them as a large piece. That way it's easy to recover from the cemented silver.
Harold
When you use copper wire, it doesn't dissolve uniformly, so in the end you risk having small bits of copper wire mixed with the silver. If the silver is targeted for the parting cell, you tend to defeat the purpose of processing the silver in a sense, by contaminating the electrolyte prematurely. Beyond that, wire is very acceptable.
I used to melt wire or any small bits of copper and cast them as a large piece. That way it's easy to recover from the cemented silver.
Harold
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Yes. The larger the piece, the better it will serve you. The reduced area, which comes with melting, will be slower to react, but it will still do the job, it just takes longer.
A couple things to think about. If your solution is highly concentrated, it's not unusual for the silver to plate out so densely that it forms an impervious layer on the copper, stopping all action. So then, dilute the solution, and insure that it has a little free nitric. If speed is an issue, present as much area as you can. I used to use multiple pieces, but avoided wire because my silver was parted in a silver cell once recovered. I tried to keep it as pure as I could, therefore I didn't use wire.
If you process waste that contains any platinum or palladium, you're going to end up with both in your silver. Platinum will readily dissolve in nitric in the presence of silver, so it's hard to avoid, and palladium readily dissolves in nitric. Both are eager to follow silver, so it's actually a good way to concentrate each for future processing. They are recovered in the silver cell, from the slimes.
If you re-use the silver a few times, it can become heavily loaded with the platinum metals, complicating parting in the cell. Reuse your silver only when absolutely necessary if it contains those metals.
Be certain to test your solution after you cement the silver. If it has a green tint, you may have values present. Both platinum and palladium are last to come down, after all of the silver is down. It can take a day or longer for all of it to cement. You want a lack of reaction when testing with stannous chloride.
One more thing. I'm not keen on using plastics in the refinery, but when you cement silver, because you use heavy pieces of copper that can easily break glass, my routine was to use 5 quart ice cream buckets. They'll stand a large amount of abuse as long as they're not cold, and they can be incinerated when they are no longer useful, so you can recover the traces of silver that slowly accumulate on the surface. I highly recommend you NOT use glassware unless it is very robust, and your pieces of copper are not excessively large.
Harold
A couple things to think about. If your solution is highly concentrated, it's not unusual for the silver to plate out so densely that it forms an impervious layer on the copper, stopping all action. So then, dilute the solution, and insure that it has a little free nitric. If speed is an issue, present as much area as you can. I used to use multiple pieces, but avoided wire because my silver was parted in a silver cell once recovered. I tried to keep it as pure as I could, therefore I didn't use wire.
If you process waste that contains any platinum or palladium, you're going to end up with both in your silver. Platinum will readily dissolve in nitric in the presence of silver, so it's hard to avoid, and palladium readily dissolves in nitric. Both are eager to follow silver, so it's actually a good way to concentrate each for future processing. They are recovered in the silver cell, from the slimes.
If you re-use the silver a few times, it can become heavily loaded with the platinum metals, complicating parting in the cell. Reuse your silver only when absolutely necessary if it contains those metals.
Be certain to test your solution after you cement the silver. If it has a green tint, you may have values present. Both platinum and palladium are last to come down, after all of the silver is down. It can take a day or longer for all of it to cement. You want a lack of reaction when testing with stannous chloride.
One more thing. I'm not keen on using plastics in the refinery, but when you cement silver, because you use heavy pieces of copper that can easily break glass, my routine was to use 5 quart ice cream buckets. They'll stand a large amount of abuse as long as they're not cold, and they can be incinerated when they are no longer useful, so you can recover the traces of silver that slowly accumulate on the surface. I highly recommend you NOT use glassware unless it is very robust, and your pieces of copper are not excessively large.
Harold
