# How Far to Refine Your Silver?



## Bushka (Dec 29, 2012)

As mentioned on another thread, I have a batch of silver chloride that should theoretically yield about 650 grams of silver. It seems there are a number of options I could take, but I do not know what I will end up with value-wise with each option. I see some options as:

1. Convert the AgCl to silver powder through lye or sulfuric and iron, etc and then sell the powder, or melt it down and sell the ingot, which might be less than 98% silver as I am not sure of what unknown contaminants might be carried along,

2. Convert the AgCl as above, then dissolve in nitric acid and drop out with copper, increasing the purity to maybe 99%,

3. Dissolve in nitric acid as above and set up a silver cell to try and get 999 or 9999 silver, maybe losing yield in the process.

4. Ideally it seems the best way to assure good purity is to dissolve in nitric acid, drop with copper and clean well, then redissolve and electrolyze in a silver cell to get 9999.

My problem is I do not know the economics of each method as I don't know how to sell the silver and what price it will bring in each form (powder or ingot). It appears that some go to jewelers to sell silver. Do you get the spot price?

If I use 2.8 ml 70% nitric/1g silver, I need about 1.8 liters of nitric acid, which costs at least $75 -- and I'd need to double that if I wanted to try option 4 above. Is it worth it to use relatively expensive nitric acid to bump up the purity a few percentage, or can I get decent money with something like 95% purity?

I should say that if it is a wash financially either way, I'd probably shoot for the highest purity. I'd like to try the nitric/silver cell method and see what happens. All in all, between nitric acid and buying a $50 MAPP torch for melting silver, it could cost over $200 just to produce a bit over 16 ounces of silver.

Any comments are welcome!


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## etack (Dec 29, 2012)

If you are not getting nitric cheap then have it toll refined or sell it. If it costs 200.00 for 1# or 452 grams than you will lose money.

I personally don't refine silver I collect and send it on. You don't get paid any more for it and it just takes up time. Some members have success selling poured bars most will not get much more that 96% of spot.

Eric


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## g_axelsson (Dec 29, 2012)

You do not need to dissolve all silver when setting up a silver cell. The only silver you need to dissolve in nitric acid is the silver for the electrolyte and that amount is depending on the size of the cell. The rest is melted into an anode.

Göran


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## NobleMetalWorks (Dec 30, 2012)

I would convert the chloride to metallic, then retain until you have collected enough silver to make it viable to invest in the equipment required to refine it further.

If you do decide to run a Balbach-Thum, or Moebius cell, both use silver concentrations in the range of 30-150 g dm-3. And if you want to create large, well separated, non-adherent crystallites of silver, which makes it easier to remove, wash and dry the silver, you will also want to have CuNO3 (copper) present in your solution. So you need a good amount of silver and copper in order to properly operate a Blabach-Thum or Moebius cell. A lot of times, the expense of the silver/copper in your electrolytic solution is worth far more than the silver you are refining.

If you want to set up something small, which I think that is your intent, you might want to read the posts by Kadriver on the subject. He has done an excellent job documenting his experiences and has a lot of practical knowledge and understanding on the subject.

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=50&t=16132

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=50&t=11842&start=40

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=49&t=15603&start=20

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=51&t=12477

There are a lot of other people who have posted information as well. If you do a search you will come up with a wealth of information.

If I were you, I would set your material aside until you have enough to make it economically viable for you to refine further.

Scott


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## goldsilverpro (Dec 30, 2012)

Bushka said:


> If I use 2.8 ml 70% nitric/1g silver, I need about 1.8 liters of nitric acid, which costs at least $75 -- and I'd need to double that if I wanted to try option 4 above. Is it worth it to use relatively expensive nitric acid to bump up the purity a few percentage, or can I get decent money with something like 95% purity?



To dissolve 1 gram of silver, it takes about 1.22ml of 70% nitric acid, at most, plus an equal amount of distilled water. The nitric usage can be reduced somewhat by covering the beaker, while dissolving, with a watch glass.


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## mikeinkaty (Dec 30, 2012)

Edited 12/30/2012 9:48pm---
Here is a table I made using the 1.22ml/gram figure given by *Goldsilverpro* and my cost of nitric at $40 /Liter. It is also using 4.17ml/gram to disolve the non-silver (usually copper) components. 92.5% is assumed for the silver content. Figure about $1.80 per troy ounce of 925 Sterling for the Nitric acid needed. If you're figuring on the cost of silver going up, then you might win! Good reflux might make this cost go down. This is only an estimate and does not represent exact science! Remember that when all the metal is in solution, you ideally want all of the Nitric acid to have been consumed. Due to a lot of variables you never know exactly how much will be needed. Add the Nitric slowly!

*Silver recovery from Sterling using 70% Nitric Acid that cost $40/Liter (Without reflux)* 
Multiply the cost figure below by X/40 where X is your cost per liter for 70% Nitric. 

Ozt___Gms____h2o(ml)_hno3(ml)_Nitric_$
1_____31.1____45______45______$1.82___
2_____62.2____90______90______$3.65___
3_____93.3____134_____134_____$5.47___
4_____124.4___179_____179_____$7.29___
5_____155.5___224_____224_____$9.11___
6_____186.6___269_____269_____$10.94__
7_____217.7___313_____313_____$12.76__
8_____248.8___358_____358_____$14.58__
9_____279.9___403_____403_____$16.40__
10____311.0___448_____448_____$18.23__
11____342.1___493_____493_____$20.05__
12____373.2___537_____537_____$21.87__
13____404.3___582_____582_____$23.69__
14____435.4___627_____627_____$25.52__
15____466.6___672_____672_____$27.34__
16____497.7___717_____717_____$29.16__
17____528.8___761_____761_____$30.98__
18____559.9___806_____806_____$32.81__
19____591.0___851_____851_____$34.63__
20____622.1___896_____896_____$36.45__
21____653.2___940_____940_____$38.27__
22____684.3___985_____985_____$40.10__
23____715.4___1030____1030____$41.92__
24____746.5___1075____1075____$43.74__
25____777.6___1120____1120____$45.56__
26____808.7___1164____1164____$47.39__
27____839.8___1209____1209____$49.21__
28____870.9___1254____1254____$51.03__
50____1555.2__2239____2239____$91.13__
100___3110.4__4478____4478____$182.26_
200___6220.7__8956____8956____$364.52_


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## goldsilverpro (Dec 30, 2012)

mikeinkaty said:


> Here is a table I made using the 1.22ml/gram figure given by *Goldsilverpro* and my cost of nitric at $40 /Liter. It is also using 3.66ml/gram to disolve the non-Sterling (base metal) components. It is also using 92.5% as the pure silver content of the Sterling. Figure about $1.75 per gram of 925 Sterling for the Nitric acid needed. If you're figuring on the cost of silver going up, then you might win! Good reflux might make this cost go down. This is only an estimate and does not represent exact science!
> 
> (Goldsilverpro - is 3x to disolve the base metals about correct? let me know and I will change the table. If it should be 1x then the per gram cost would go down to about $1.50 per gram of 925 Sterling.)
> 
> ...



It takes 3.4 times more nitric for copper than for silver, per gram. That would be 4.15ml/g for Cu.


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## Bushka (Dec 31, 2012)

etack said:


> If you are not getting nitric cheap then have it toll refined or sell it. If it costs 200.00 for 1# or 452 grams than you will lose money.
> 
> I personally don't refine silver I collect and send it on. You don't get paid any more for it and it just takes up time. Some members have success selling poured bars most will not get much more that 96% of spot.
> 
> Eric



Not sure what you are saying. You get the same price for unrefined silver (like say .98 silver powder) as you get for 999 ingots?


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## Bushka (Dec 31, 2012)

g_axelsson said:


> You do not need to dissolve all silver when setting up a silver cell. The only silver you need to dissolve in nitric acid is the silver for the electrolyte and that amount is depending on the size of the cell. The rest is melted into an anode.
> 
> Göran



Good point. I believe my AgCl is probably much more pure than sterling, since it was prepared in a school lab, and probably not from sterling silver. I would guess that it could produce a pretty clean anode when melted. I'll do some more research on this forum, but maybe you can answer one question about the silver cell. I presume you cannot process all the silver in solution, but merely save it for the next batch of silver. However, if you only do one batch, how much silver can you expect to lose in solution? For instance, if I process 1 lb or 454 g of pretty clean silver ingot, how much will I likely lose to the solution when I'm finished?


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## Bushka (Dec 31, 2012)

Thanks to you other guys for the advice. I couldn't find or remember GSP's figure of 1.22 ml nitric.

Where can I find information on prices for silver powder vs ingots and various purities?


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## etack (Dec 31, 2012)

Bushka said:


> etack said:
> 
> 
> > If you are not getting nitric cheap then have it toll refined or sell it. If it costs 200.00 for 1# or 452 grams than you will lose money.
> ...




Yep that's what I am saying. It all goes to the refinery that send it thought there cells so why waste my time on it unless it's just for fun.

Eric


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## goldsilverpro (Dec 31, 2012)

Bushka said:


> g_axelsson said:
> 
> 
> > You do not need to dissolve all silver when setting up a silver cell. The only silver you need to dissolve in nitric acid is the silver for the electrolyte and that amount is depending on the size of the cell. The rest is melted into an anode.
> ...



The silver cell is not a one batch process. It is more of a continual process. You have about 20 oz of silver and at least 2 or 3 oz will be tied up in the solution. There will probably be some in the anode slimes. It will cost money to set up the silver cell.

Were I you, I would skip the silver cell. If the AgCl is fairly pure to start with, and it probably is, I would concentrate on getting 100% of it converted to silver powder. Then you could easily melt it. As others have said, the trick is to get it finely ground. As you probably know, once AgCl has been dried, it becomes crystallized and is much more difficult to convert.

The simplest way is probably the blender method, using NaOH and Karo syrup, which has already been discussed. I would suggest doing it in small batches, with the blender only about 1/4-1/3 full. For each 31.1 grams of AgCl, it will theoretically take about 15g of NaOH, 10ml of Karo syrup, and 100ml of water - tap water is OK. To be on the safe side, I always add an extra 10% of each, which would make it, for 31.1g of AgCl, 16.5g of NaOH, 11ml of Karo syrup, and 110ml of water. Therefore, the total volume occupied per 31.1g of AgCl would be about 130-140ml, or so.

Considering the state of the AgCl you have, even with the blender you may not get 100% conversion. Incomplete conversion will promptly show up when you try to melt the silver. It's not pretty and breathing the toxic fumes coming off the molten AgCl is quite hazardous.

You can easily test for unconverted AgCl in the Ag powder. It's better to test it while it's still wet. This is a sensitive test. Before starting, everything you use must be clean and well rinsed with distilled water.

(1) Dip out about a gram, or so, of the Ag powder and put it into a 100ml beaker. Add about 20ml of distilled water and stir well. Allow to settle and pour off only the water. Repeat 5 or 6 times. You must rinse out all of the chloride. Hot distilled water would be best. With each rinse, also rinse down the inside of the beaker with distilled water from a squirt bottle. To test for complete removal of the chlorides in the rinses, put a few ml of the rinse water in a small beaker and add a drop or two of silver nitrate solution. A white cloud indicates chlorides and more rinsing is needed.

(2) When all the chlorides are out, pour off the rinse and add a little nitric acid (2 or 3 ml) and an equal amount of distilled water. When the Ag has completely dissolved, the presence of a white cloud or a settled white powder indicates unconverted AgCl.


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## Bushka (Dec 31, 2012)

goldsilverpro said:


> You can easily test for unconverted AgCl in the Ag powder. It's better to test it while it's still wet. This is a sensitive test. Before starting, everything you use must be clean and well rinsed with distilled water.
> 
> (1) Dip out about a gram, or so, of the Ag powder and put it into a 100ml beaker. Add about 20ml of distilled water and stir well. Allow to settle and pour off only the water. Repeat 5 or 6 times. You must rinse out all of the chloride. Hot distilled water would be best. With each rinse, also rinse down the inside of the beaker with distilled water from a squirt bottle. To test for complete removal of the chlorides in the rinses, put a few ml of the rinse water in a small beaker and add a drop or two of silver nitrate solution. A white cloud indicates chlorides and more rinsing is needed.
> 
> (2) When all the chlorides are out, pour off the rinse and add a little nitric acid (2 or 3 ml) and an equal amount of distilled water. When the Ag has completely dissolved, the presence of a white cloud or a settled white powder indicates unconverted AgCl.



Thank you for the advice, GSP. In step 1 I assume you are removing chlorides from the conversion of AgCl to AgO and ultimately to Ag. This would form NaCl and I'm sure other Cl- species. This is what we are rinsing out of the Ag, right? I guess my question is why is step 1 necessary? Are chlorides likely to precip out or otherwise interfere with seeing any residual AgCl in step 2?

One other concern I have is that I've always assumed I'd have all the AgCl in a dissolved liquid state at some point (Probably after dissolving the cemented silver in nitric acid). That is when I was going to filter the solution to remove any small debris. I don't believe I have a lot of foreign material, but I do believe there are some very tiny bits of wood and dust there. Maybe these will just burn off and be taken care of by the borax?


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## goldsilverpro (Dec 31, 2012)

Bushka said:


> goldsilverpro said:
> 
> 
> > You can easily test for unconverted AgCl in the Ag powder. It's better to test it while it's still wet. This is a sensitive test. Before starting, everything you use must be clean and well rinsed with distilled water.
> ...



The chlorides, of course, are part of the liquid in the converted Ag powder. If you don't rinse them out completely, they will combine with the dissolved silver in step 2 and form silver chloride. This will always indicate, or give a false positive, that the conversion wasn't complete, even if it was.

Silver chloride is not soluble in nitric acid. It is soluble in cyanide, thiosulfate, ammonia, strong sodium chloride solutions, and very slightly in full strength aqua regia. That's about it for common things.


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## Bushka (Dec 31, 2012)

goldsilverpro said:


> Bushka said:
> 
> 
> > goldsilverpro said:
> ...



OK, I see how the test is contaminated by Cl when you add the nitric. Thanks again!


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## Bushka (Jan 5, 2013)

GSP - 

1. Regarding your test for unconverted AgCl in the Ag cement: I do not have nitric acid, and therefore also no AgNO3. I had an alternate idea for testing residual AgCl. I do have ammonia (I am well aware of the hazards). How about doing this instead: Wash the silver cement with several batches of hot water to assure most of the chlorides are flushed out. Then, add ammonia to the silver. Some heat will help any residual AgCl to dissolve. Pour off the ammonia through a filter and drop a clean piece of copper in the solution. If nothing happens, then there was no AgCl left. If it plates out silver, then there must have been some AgCl left. Also, I can look for a bluish tint which would indicate copper ions entering solution. Anything wrong with this method? (Again, observing the hazards).

2. My silver chloride has some dry HCl in it from when I originally cleaned it up. Is this likely to interfere with the NaOH/syrup conversion? I know the HCl will neutralizer the NaOH, but I didn't know if residual HCl would be enough to worry about.

Thanks!


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## goldsilverpro (Jan 5, 2013)

Bushka said:


> GSP -
> 
> 1. Regarding your test for unconverted AgCl in the Ag cement: I do not have nitric acid, and therefore also no AgNO3. I had an alternate idea for testing residual AgCl. I do have ammonia (I am well aware of the hazards). How about doing this instead: Wash the silver cement with several batches of hot water to assure most of the chlorides are flushed out. Then, add ammonia to the silver. Some heat will help any residual AgCl to dissolve. Pour off the ammonia through a filter and drop a clean piece of copper in the solution. If nothing happens, then there was no AgCl left. If it plates out silver, then there must have been some AgCl left. Also, I can look for a bluish tint which would indicate copper ions entering solution. Anything wrong with this method? (Again, observing the hazards).
> 
> ...


1. Sounds logical, if the copper will dissolve. I've never tried to cement silver from an ammoniacal complex. 

After filtering the ammonia solution, you could re-acidify it with a little HCl. If silver is present, AgCl will form. Make sure everything you use has been well rinsed with distilled water before making any of these tests.

2. I can't see a little HCl causing problems with the conversion.


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## Bushka (Jan 5, 2013)

goldsilverpro said:


> Bushka said:
> 
> 
> > GSP -
> ...



OK. Maybe acidifying with HCl would be better. I could try both. I just did a small batch per your recipe, and while everything turned dark grey, there are little chunks of white remaining. I didn't put anything in the blender - just in a beaker to see what happens. I'm leaving the solution to sit for awhile to see if the white chunks begin to convert to AgO.


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## Bushka (Jan 6, 2013)

OK, so here's where I'm at:

Last night I added lye to 31 g silver chloride. I found that there were lots of small white chunks still there, so I added a little more lye to see what happened. I noticed that the precip was grey, but when I sprinkled lye onto the surface of the precip, it turned black wherever the lye touched. I would mix this in and add more lye and the same thing would happen. It almost seemed like the dark spots turned back into grey after some time, though I'm not sure about this. I didn't want to add too much lye, so stopped playing around with it. I probably had about 1.5 times the recipe of lye. This morning it looked like there were still plenty of white chunks still there, but I think some of them did convert. It's hard to quantify any of this. I added syrup this morning and the mixture did heat up. I probably added 1.5 times the recipe. After continued stirring and then letting it sit for about an hour, I took the photo below. There seems to be a light grey layer with little bits of shiny silver, and then a dark powdery layer on top, with a greenish/orange liquid above.

I'm trying to figure out what I'm left with here. Is the dark powder also converted silver, or is it AgO awaiting more syrup? I thought of adding more syrup and checking the temperature with a probe to see if it heats up again. Before going any further I thought I'd ask people who've done it before.

I should add that the silver chloride did have HCl dried in it from a previous clean up wash. I flushed the HCl with some water, but there's still plenty dried with the silver chloride, if that matters much.

Thanks!


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## goldsilverpro (Jan 6, 2013)

The color of the solution is normal in this process.

I'm not 100% sure, but I think the darker powder on top could be finely divided silver and the gray is more chunky. Often, with metal powders, the more finely divided, the darker the powder. Since you did nothing to break up the dry crystallized silver chloride, it is very possible that the gray particles are a gray coating covering some unconverted silver chloride. It's hard to tell, but it sort of looks like that to me.

Converting dried silver chloride is always a problem. As a precaution, I would probably transfer everything in the beaker to a blender and let it run for a few minutes. Hopefully, the blender seals will stand up to the excess NaOH. They probably will be OK. You shouldn't need to add any more chemicals, since there is already an excess.

After this, if silver chloride appears when testing for completeness, you might filter and rinse the powder VERY WELL and then try to leach the AgCl out of the entire lot of powder with ammonia. Filter and rinse well. If that works, you could avoid the dreaded presence of silver chloride when you melt the silver. You could then acidify the ammonia solution with HCl and then collect the AgCl that forms.

I'm not guaranteeing anything. That's my best bet at this time. This might change depending on your results.


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## Bushka (Jan 6, 2013)

I've been avoiding the blender. There's something about lye and hi speed motion that I don't like! I'll give it a try tomorrow when I pick up the old blender from work. Maybe I can put a clear bag over the whole thing in case something splashes out. I'll report back.

Thanks!


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## Bushka (Jan 8, 2013)

OK, I've completed a couple of batches with the blender and it works great! It pulverizes the AgCl down into a powder. I'm using GSP's recipe, but I find that if I add some NaOH crystals to the wet AgO, it turns near black from greyish. Does this mean the conversion hasn't completed, or there isn't enough NaOH, or does it mean something else? In the blender, it seems to convert quickly. How long should I wait before adding syrup? As an example, I just made a 3x batch, which is about 90 g AgCl. I blended the AgCl in water for about 30 seconds, then added the lye and blended for another 60 seconds. Should I expect the conversion to be complete this quickly?

Thanks!


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## Bushka (Jan 9, 2013)

I'm not sure if I'm getting 100% conversion to AgO. The second pic shows a batch of silver. I don't know if it shows on the pic, but it does look like there are some small whitish specs that might be AgCl. I took a scoop out of the silver, and added some lye crystals (first pic). I have to assume that the dark color indicates formation of AgO, which means the silver is not fully converted. Pure silver would not turn black like this, correct?

As mentioned in my last post, the dark color is confusing me. It seems like the very dark color of AgO doesn't last. If I sprinkle lye on AgCl in solution, it turns black wherever it touches. However, if I add an excess of lye (like double the recipe from GSP), the whole batch of AgCl does not turn that dark grey/black. Is there an equilibrium between the AgCl on one side and AgO on the other, or is the conversion to AgO considered irreversible (or let's say to completion)?

Just a bit confused here.


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## goldsilverpro (Jan 9, 2013)

For many things, I never worried much about colors. In your case, I would rely mainly on the tests.


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## Anonymous (Jan 9, 2013)

Bushka said:


> I'm not sure if I'm getting 100% conversion to AgO. The second pic shows a batch of silver. I don't know if it shows on the pic, but it does look like there are some small whitish specs that might be AgCl. I took a scoop out of the silver, and added some lye crystals (first pic). I have to assume that the dark color indicates formation of AgO, which means the silver is not fully converted. Pure silver would not turn black like this, correct?
> 
> As mentioned in my last post, the dark color is confusing me. It seems like the very dark color of AgO doesn't last. If I sprinkle lye on AgCl in solution, it turns black wherever it touches. However, if I add an excess of lye (like double the recipe from GSP), the whole batch of AgCl does not turn that dark grey/black. Is there an equilibrium between the AgCl on one side and AgO on the other, or is the conversion to AgO considered irreversible (or let's say to completion)?
> 
> Just a bit confused here.


I'm not sure if it's the case with you too, but I've processed keyboard mylars, and from which I've read, it's just silver, with no other metals mixed in, for the most part. But, as I even processed my mylars, I noticed that after dropping the silver and doing a filtration, I ended up with some dark grey/blackish power in the filter. 

The grey/blackish powder seem to stay in the filter after doing a rinse of the silver. I read that it may be carbon, which won't react to Nitric Acid. I'm still learning, but it might be carbon in whatever you've been processing.

If it's not that much, put it to the side and after rinsing it good, let it dry out, then try to melt it.

Kevin


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## Bushka (Jan 10, 2013)

GSP: Thanks for the advice to ignore color and go with the test results.

testerman: Could the black fines be silver as GSP mentions? He says metal powders tend to be darker when they are finer pieces. I highly doubt there is that much carbon in my AgCl. The AgCl was originally a lab experiment for students, so I don't see any reason there would be carbon in the AgCl.

Thanks!

Dan


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## butcher (Jan 10, 2013)

Dan, I also doubt it is carbon, probably just fine silver of some sort, silver chloride in sunlight will darken to a violet to black color silver metal (photography), even if this was some type of carbon it would not hurt any thing.

testerman, Actually nitric acid will react with carbon it can make carbon burn violently (like in gunpowder).


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## Anonymous (Jan 10, 2013)

butcher said:


> testerman, Actually nitric acid will react with carbon it can make carbon burn violently (like in gunpowder).


Thanks *butcher*. I had read that it wouldn't react to it. Now I know.

This is the picture I posted with the black substance that didn't rinse through my washes. Are we saying this could be silver?
It's the first picture on that page.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=50&t=16596&start=20

Kevin


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## butcher (Jan 10, 2013)

It would be very hard to tell what something is by looking at it or by the color, sometimes we can get a good idea of what it maybe, when we know what went in to obtaining a substance, but this is just speculation mostly, a white powder can be many things, a black powder can also be many things, the same with solutions colors give us clues but can also fool us if we go strictly by color, a yellow solution can be gold chloride, but a yellow solution of iron chloride can look just gold chloride.

Colors can be helpful indicators, but also cannot be relied on.

Further testing many times is the only way to know for sure what you have.

Notice where GSP said he rarely paid attention to color, many time I would say he used color to judge what may have been happening, or what he may have had, but then again, He knew that solutions and powders can vary widely in color, and that He could not count on just color to be sure what he had.

Colors of a substance can also be influenced by many factors also, contamination, concentration, temperature, light, dissolved gases, and many other things.

I guess I am trying to say colors are helpful but they in reality do not tell you much.

This is hard to explain.


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## Anonymous (Jan 10, 2013)

*Butcher*.... it's not hard for you to explain, or, at least I understand what you're saying. I can see what you're talking about, and you're right. I would need to further test the substance and determine what I have according to the results of the test(s).

You've made an excellent point. Since I've been getting small amounts of the black substance during my refining, I'll put all of batches in the same jar until I run out of the material I'm working with.

Thanks for the info

Kevin


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## butcher (Jan 11, 2013)

Good idea maybe that black powder is gold. :lol:


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## Anonymous (Jan 11, 2013)

butcher said:


> Good idea maybe that black powder is gold. :lol:


Yeah right :lol: I wish.

Kevin


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## Bushka (Jan 17, 2013)

Well, I've converted all my silver chloride to silver cement with the blender and have found that I still have large amounts (maybe 10%???) of silver chloride that didn't convert. I don't know if it is because of chunks or if I didn't give the reaction enough time before adding syrup. It seemed like the blender did a good job of breaking up the small chunks.

I'm soaking the silver in ammonia and then pouring off the ammonia the next day. Just to experiment, I hydrolyzed one batch of ammonia and then tested for completion with a copper bar, and I added lye and syrup to the other one.

My real issue is that I guess because of the blender I have a lot of very fine silver that goes right through my coffee filters (even 5 of them). Not having a real lab setup with sintered vacuum filters and so on, are there any tricks to dealing with such fine silver other than waiting 3 days for it to settle? I'm thinking of putting the silver back in the blender but I can imagine creating even smaller particles. It's impossible to wash such fine silver.

Thanks!


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## etack (Jan 17, 2013)

*DON'T LET YOUR AMMONIA AND SILVER SOLUTION DRY IT WILL CREATE AN EXPLOZIVE COMPOUND IF MOVED*

just an FYI

Eric


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## Bushka (Jan 17, 2013)

Thank you, Eric. I'm aware of the hazards, and should probably say so anytime I mention ammonia. For the record, I don' think it is as easy to make the explosive compound as some think. Awhile back, over a year ago, I did process some silver with ammonia unaware of the hazards. I let some of the solutions I made dry up and never had any issues, luckily.


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## butcher (Jan 17, 2013)

Several plating businesses have blown up, these were professionals who knew the dangers.

Sometimes accidents happen from the things we least expect or become complacent with.

We may get by with making gun powder several times with very little reaction from our powder, but we may make a batch that will react just like it is supposed to, if we get complacent thinking we don’t have to wet it to grind the ingredients separately, because we made it so many times with little reaction, or done it this way with no problems before, we may just find ourselves in a situation we could regret, having trouble opening doors with the hook where our hand used to be.

This, and the fact we have some people who really do not know the dangers or possibility of these dangers, they also may not follow strict procedures when dealing with chemicals or reactions, sometimes getting very creative, thinking what would it hurt to put a little of this in the mix, I can skip that step, it would be easier to mix all of the powders and grind them, lets see what happens when I put some of this...

For these reasons it is good to always stress the dangers, and also always keep them in mind ourselves, when working.


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## Bushka (Jan 18, 2013)

Point taken, Butcher. Any suggestions on how to wash silver fines?


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## butcher (Jan 18, 2013)

I knew you understood that Bushka, I just felt I needed to point it out.

As far as washing silver I would follow GSP's instructions, he also give's ways to test your wash to tell if it has copper.


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## Bushka (Jan 19, 2013)

I'll look for his instructions. It's just that the fines/powder can take several days to settle. Unless I find a way to filter it, I'm at a loss.

Thanks.


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## butcher (Jan 19, 2013)

I normally do not have much trouble with silver settling, unless it is silver chloride.

Most any time I can let a substance settle, so I can decant it, I prefer that to filtering, and will then just filter the more clear liquid.

There are several tricks I use when filtering, depending on what I am working with, this necessarily does not apply to your particular problem here, but may give you some ideas.

If a fine powder goes through a filter, you can wait till the filter begins to clog with material then re-filtering the fines that passed through the first time. 

Shredded filter papers, or toilet paper, add this to the filter, to catch the fine particles.

Filter the bulk with a fast filter, and then re-filter liquid again with a coarser paper.

Decant the solution from the bulk of your material to be processed let the fines settle in a jar and get them at a later date.

For hard to filter stuff, 
Concentrating or sometimes dilution, settle decanting, some time’s screening out the larger malarial, sometimes using the material in the screen to help capture the bulk, then using the bulk material in the screen to capture the finer material when pouring the previously filtered material back over the bulk of the material in the screen.

Using the fiberglass insulation, Charmin plug, re filtering through finer filters as needed. 

Using the shredded filter or toilet paper and screening or filtering dry and incinerate.

There are many other tricks you can pick up along the way to help.
But even then sometimes it is still just a pain.


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## Bushka (Jan 21, 2013)

That does give me some ideas to try.

Thanks!


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## Bushka (Jan 26, 2013)

It seems to be difficult to get all the silver chloride out of the silver (or at least time consuming). I don't want to put silver back in the blender for fear of making all the silver fine as powder and difficult to clean. I'm thinking of going to Plan B, which is to buy some nitric acid. Here's my idea:

I had 800 g AgCl, which is now maybe 90% silver and 10% AgCl all mixed up, with some tiny chunks of AgCl coated with silver. My thought was to dissolve the silver with nitric acid (should take less than 1 liter, right?) and what doesn't dissolve should be AgCl only. I can then reprocess the AgCl, redissolve with nitric and repeat until the AgCl is all gone. I would then take the silver nitrate and drop the silver with copper, or maybe electrolyze until depleted, and then drop the remainder with copper.

Will this work? Also, since I started with AgCl and not sterling, I don't expect much copper. Will dropping with copper contaminate the silver? Does it really matter if I will be paid by the purity after analysis anyway?

Thanks.


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## Bushka (Jan 29, 2013)

Bump for any help on whether my last post will work OK or not.

Thanks!


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## butcher (Jan 29, 2013)

I do not see why it would not work.
If you can afford the nitric.


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## Anonymous (Jan 29, 2013)

I agree with *butcher*. If you can afford it, use the nitric. It'll dissolve the silver and it'll be easier for you to recover it later on, especially if copper is the main/only contaminant.

Kevin


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## Bushka (Jan 30, 2013)

Yeah, I've been avoiding the nitric because of the cost. I expect to get close to 600 g of silver and buying a liter of nitric not to mention a MAPP torch puts a big dent in any profit.

Thanks again!

Dan


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## Bushka (Feb 17, 2013)

OK, I finally acquired some nitric acid locally. It's 50% nitric, but it is 50% v/v. I've searched the forum but I can't find anything on what the recommended 70% nitric actually is. Are we talking w/v or v/v or what? Everybody always just says use something like 1.2 ml 70% nitric to dissolve 1 g of silver. I need to know as I want to be sure I am dissolving enough silver for the amount of 50% v/v nitric that I'm using. I only have 1 liter and something like 600 g of silver. Anybody know the conversion from 50% v/v to 70% of whatever it is?


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## Anonymous (Feb 17, 2013)

Bushka said:


> OK, I finally acquired some nitric acid locally. It's 50% nitric, but it is 50% v/v. I've searched the forum but I can't find anything on what the recommended 70% nitric actually is. Are we talking w/v or v/v or what? Everybody always just says use something like 1.2 ml 70% nitric to dissolve 1 g of silver. I need to know as I want to be sure I am dissolving enough silver for the amount of 50% v/v nitric that I'm using. I only have 1 liter and something like 600 g of silver. Anybody know the conversion from 50% v/v to 70% of whatever it is?


Why not take 1 gram of silver and 1.17ml of Nitric and 1.17ml of water or peroxide and see how fast it'll dissolve. I'm using 70% nitric (actually it's 69.5%) and it starts to dissolve silver within seconds after putting them in the acid.

If anything, I would suspect the nitric would take a bit longer to dissolve the silver. Then again, it may be just as 70% if you were to use a little heat to the vessel. 

w/v and v/v.... What are you talking about? weight per volume and volume per volume?

Kevin


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## butcher (Feb 17, 2013)

commercial azeotropic nitric acid 68% w/w

http://www.thechemicalblog.co.uk/what-do-vv-ww-wv-andvw-mean/


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## Anonymous (Feb 17, 2013)

butcher said:


> commercial azeotropic nitric acid 68% w/w
> 
> http://www.thechemicalblog.co.uk/what-do-vv-ww-wv-andvw-mean/


Thanks *butcher*, now I understand and I'll be able to relate to it when I see it again in threads.

Kevin


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## Bushka (Feb 18, 2013)

So I take it then that when everybody says 70% nitric they are talking 68% w/w. I don't suppose anybody has already done the math to convert that to v/v??? I tried to dissolve a little silver last night, but it was bitterly cold and my heating set up was less than well thought out. I was hoping the reaction would get going quickly enough sitting in some warm water. Between that and a hair dryer I did get a little reaction but it never took off. Then when I checked on things later the warm water bath had frozen solid! I'll try plan B tonight.


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## Anonymous (Feb 18, 2013)

Bushka said:


> So I take it then that when everybody says 70% nitric they are talking 68% w/w.


Not really, when some people say 70% nitric, they're talking about 70% nitric. Because, from what I have learned so far, 68%+ is also considered 70%, or, at least it's just as reactive as 70%. So, if you have 68% nitric, it should dissolve your silver, if it is indeed silver.



Bushka said:


> I don't suppose anybody has already done the math to convert that to v/v???


I hav no idea, but if it were me, I would first measure my water I'm going to add, then measure the nitric, then add the nitric to the water. Once your silver is in the solution, wait a few seconds and a reaction should start. If a reaction doesn't start, add more nitric, (about 3 ml at a time) wait for the reaction after each addition of nitric. If still no reaction, then add some heat to the vessel. If still no reaction, then either your Nitric is spent/too weak or the metal you're trying to dissolve isn't silver, or it's a metal nitric won't dissolve. I can't see it not dissolving your material, if it is indeed silver.



Bushka said:


> I tried to dissolve a little silver last night, but it was bitterly cold and my heating set up was less than well thought out. I was hoping the reaction would get going quickly enough sitting in some warm water. Between that and a hair dryer I did get a little reaction but it never took off. Then when I checked on things later the warm water bath had frozen solid! I'll try plan B tonight.


You should have added a bit more nitric to the solution. I'm almost sure, but not positive, but if it's that cold outside, then a hair dryer probably wouldn't be sufficient enough to heat the vessel. How was the dryer positioned? To the side of the vessel? Real close to the side of the vessel? Blowing from the top of the vessel? How cold was it outside?

I'm nowhere near a professional in refining silver, but I've refined silver (.925) and I've had great success so far and not a single problem as of yet. 

As far as what you should yield from what you have is just a maybe, possibility or hopefully. If haven't processed that same exact bath of material or even closely similar to it, you can't tell what you should get. I can see you saying "*I hope I get X amount of grams out of this*". 

You never showed any photos of the material you was working with. Do yourself a favor and take pictures along with notes. It can help others determine what is going on and what must have went wrong during the process(es). I do that myself, which I've did, and when I uploaded images of what was what, the members here were able to give a general idea of what may have happened, just by looking at the pictures. Believe me... take pictures and take notes. It'll make the world of difference when you ask for help.

But get you a hot plate and a heat gun. A hair dryer is good for certain things, (I even have one myself), but for the refining and processing of gold and silver, I'll use a heat gun, if needed and not a hair dryer.

Kevin


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## Bushka (Feb 19, 2013)

Thanks Kevin. I actually did post a number of photos earlier in this thread, which has been mostly about trying to convert AgCl to silver through lye and syrup. As you may recall from above, I've decided to bite the bullet and get the nitric. I'm just being super cautious with the first test of dissolving my cement. I'm looking for a cheap (free?) hot plate but I'm concerned even with that because I'm using an old Skippy jar, which isn't pyrex. I don't want to over heat the bottom and end up with cracked glass and silver nitrate everywhere. I was able to heat my first test batch (50 ml nitric, 50 ml dist. water) in a dehydrator, which is a metal box that blows hot air. I don't want to use this again as it's really meant for food, but I really didn't want partially reacted nitric/silver sitting around the house. It looks like heating it up helped the reaction a lot, as did adding much more silver cement. It never got to the point where it was bubbling and frothing like you see on Youtube, but I think you probably lose more NO2 that way, too. I kept a plate of glass over the jar during the reaction. I kept adding silver to excess, and I think now most of what is sitting on the bottom is more pure silver chloride. I'll separate that out and give it the lye treatment again. So if I have enough nitric, I'll process all my cement, which could well be 10 or 20% AgCl. Then I'll lye/karo the AgCl and redissolve with nitric again... repeating until all AgCl is gone.

Do you use plain glass jars or pyrex lab glassware, and do you heat on a hot plate?


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## Anonymous (Feb 19, 2013)

Bushka said:


> Thanks Kevin. I actually did post a number of photos earlier in this thread, which has been mostly about trying to convert AgCl to silver through lye and syrup. As you may recall from above, I've decided to bite the bullet and get the nitric. I'm just being super cautious with the first test of dissolving my cement. I'm looking for a cheap (free?) hot plate but I'm concerned even with that because I'm using an old Skippy jar, which isn't pyrex. I don't want to over heat the bottom and end up with cracked glass and silver nitrate everywhere. I was able to heat my first test batch (50 ml nitric, 50 ml dist. water) in a dehydrator, which is a metal box that blows hot air. I don't want to use this again as it's really meant for food, but I really didn't want partially reacted nitric/silver sitting around the house. It looks like heating it up helped the reaction a lot, as did adding much more silver cement. It never got to the point where it was bubbling and frothing like you see on Youtube, but I think you probably lose more NO2 that way, too. I kept a plate of glass over the jar during the reaction. I kept adding silver to excess, and I think now most of what is sitting on the bottom is more pure silver chloride. I'll separate that out and give it the lye treatment again. So if I have enough nitric, I'll process all my cement, which could well be 10 or 20% AgCl. Then I'll lye/karo the AgCl and redissolve with nitric again... repeating until all AgCl is gone.
> 
> Do you use plain glass jars or pyrex lab glassware, and do you heat on a hot plate?


*No# 1.* STOP using that Skippy jar with heat. You're asking for trouble.
*No# 2.* Go to the thrift store/goodwill and buy you a hotplate and some glass jars. I have plenty that are my beakers and they're thicker and taller than beakers too. Not sure if they're heat tested, but I use them as vessels. I do have and use Pyrex, but talk is not to use them and use Corning Ware.

Personally, I use Pyrex dishes to incinerate/heat on a hotplate and haven't had a problem as of yet. As far as incinerating, I've used a MAPP torch on my Pyrex numerous times and nothing went wrong (not saying it never will). But the trick to keep it from going into thermal shock (even in the summertime) is to place it on top of insulating blanket (the type used for insulating the inside of kilns and furnaces). The insulation (my theory) keeps the glass from coming into contact with the surface (wood/glass/metal/cement), which I believe causes them to crack/break/shatter, and helps to keep the glass hot, yet, cool enough to not overheat. 

If you do use a Pyrex on a coil hot plate (I do it myself), just place it in a bigger pot or metal vessel, so that way, if it should crack, you won't lose anything. But, putting pyrex in a metal vessel and then placing it on a coil hot plate should pose no threat to the pyrex dish. Depending on what you're working with, you can even ad some water to the vessel, then place the pyrex inside.

*No# 3.* If that dehydrator has been used to do any processing, I hope you know it should NEVER EVER AGAIN be used for human consumption. If it works for you, you might as well keep using it because I hope you don't plan on dehydrating and more food with that. I'd hate to hear that you dehydrated foods, vacuum sealed them, then years later when you opened them up and ate them, you got poisoned. Trust me on this one. It can NEVER be used again for food consumption. Period.

I know there are more than one way to do a lot of what we do here, but, for me, I would simply dissolve my silver in Nitric/Peroxide, then add equal amounts of distilled water, add clean copper and let it drop the silver. Rinse with plenty of hot/boiling distilled water, let it dry, then melt the silver. Done deal.

To each their own, but using lye, syrup, salt, and other chemicals/powders to me, are just more steps to achieve the same exact thing. I'm not saying I'll never try them one day, but for now, why would I bother with all those steps? Dissolve. Drop. Wash/Rinse/Dry. Melt. To me, it's that simple, when it comes to silver.


Kevin


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## Bushka (Feb 19, 2013)

Hi Kevin. I had a couple of replies:

I poured a pot of boiling water in the Skippy jar I'm using just to see if it could take some heat, and it did not crack. So, I went ahead and used it for my first little test (sitting inside a wide glass bowl). I still don't like the idea of using it on a hot plate, though. When I mentioned Pyrex, I was thinking about the lab glassware that everyone uses, not stuff for kitchen use. I think those are fine on hot plates. Are the beakers you use from the thrift store very thick? I would think thick would be more likely to crack than thin, but I guess if it works it works.

I found 3 hot plates at the thrift store yesterday, and all three were barely warm to the touch. Maybe ebay is easier.

I'm amazed that you can actually melt silver in a pyrex bowl. I was just going to use a block of wood or something. I do have 2 small crucibles so maybe I'll use those, too. I was reading from someone in this forum that MAPP can overheat silver and vaporize some, and he recommended propane. Can't remember who recommended that. Have you tried to work with propane?

I think you are overreacting a little to the use of the dehydrator. This was a very mild paced reaction and for the most part I left the front door of the dehydrator off. Hot air was blowing from the back of the unit and out the front. I only use the dehydrator for making treats for our pets, not that that makes it less important. I've inspected the interior (stainless steel), wiping it with my finger and putting my nose to it. I let it run for an hour afterwards and will wipe it with a damp towel with bicarb tonight. In short, I think by putting a glass cover on the jar, much of the NO2 refluxed back down and/or went straight outside. I understand your concern, but if you saw what I'm talking about you might get my point. In any case using that was a one time thing just to get this batch reacted.

Also, I am planning to do what you say - drop with copper and be done with it. However, the bulk of this thread is talking about the trouble I'm having converting the AgCl to Ag. It's the AgCl, not the AgNO3 that I'm planning to reprocess with lye. I'm using the nitric to separate the silver (good) from the silver chloride (bad).

Now I gotta go find a cheap hot plate.


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## Anonymous (Feb 19, 2013)

Bushka said:


> Hi Kevin. I had a couple of replies:
> 
> I poured a pot of boiling water in the Skippy jar I'm using just to see if it could take some heat, and it did not crack. So, I went ahead and used it for my first little test (sitting inside a wide glass bowl). I still don't like the idea of using it on a hot plate, though.  When I mentioned Pyrex, I was thinking about the lab glassware that everyone uses, not stuff for kitchen use. I think those are fine on hot plates. Are the beakers you use from the thrift store very thick? I would think thick would be more likely to crack than thin, but I guess if it works it works.
> 
> ...


I do not melt silver in pyrex. I said I incinerate in a pyrex.

Lab glass (heat resistant) beakers will work on hot plates and hold up to fire. I have lab beakers that I use. I also have large glass jars from the goodwill to be used to hold my solutions in that I filter and (or) drop my silver or gold with. The Skippy jar would be good for that, not for heating solutions.

I know what type of dehydrator you're talking about. I have a dehydrator, but not the kind you have.

Also, I do use MAPP and propane. But, if I'll get less of a loss with the propane, then I'll start using it for all my silver melts. Propane does melt in the same amount of time as MAPP to me, it's just MAPP gets much hotter.
Kevin


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## Bushka (Feb 20, 2013)

testerman said:


> I do not melt silver in pyrex. I said I incinerate in a pyrex.
> 
> Lab glass (heat resistant) beakers will work on hot plates and hold up to fire. I have lab beakers that I use. I also have large glass jars from the goodwill to be used to hold my solutions in that I filter and (or) drop my silver or gold with. The Skippy jar would be good for that, not for heating solutions.
> 
> ...




Got it. I didn't know what you were incinerating, so I assumed you were melting the cement.

Thanks for your help. I'm sure I'll be posting more questions down the road!


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## River21 (Jun 4, 2021)

Oh - how the mistakes get repeated... I had a bunch of what I assumed was lightly rinsed silver chloride that dried and stored... after excess NaOH and Sugar... this is what I get... which incidentally will settle to golden liquid and the mix of stuff in it... mostly grey... some black fine (darkening color in this photo). And some whitish specks (silver chloride)zzz

The solution looks alit like a clean gold solution perfectly clear with golden yellow when settled 

I guess I have to either blend or waste Nitric?


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## Lino1406 (Jun 4, 2021)

Check a sample for silver with nitric, than few drops of k-dichromate should give a perfect red. Check for gold with AR and stannous chloride


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