# Silver Cell Capacity



## kadriver (Oct 26, 2011)

The amount of silver I have to refine has increased.

I am going to make two - 1 liter silver cells to run at the same time.

Each will be completely seperate with their own converted CPU power supplies.

This is the only way I can think of to increase the output of pure silver.

It usually takes about 3 or 4 days for one cell to make 25 to 27 troy ounces of pure silver crystals.

With two cells running at the same time, I expect to double my output.

I have all the necessary items needed to construct another cell and set them side by side.

The amount of 925 and sterling silver I expect to get will be about 12 to 15 lbs of clean metal every two weeks or so.

Here is the question for the forum:

Does this sound like the most efficient way to increase my output?

The cell I use is patterned after lazersteve's video. Is there a larger setup that would increase output and decrease the time required to form the silver crystals?

Could those on this forum who have larger setups (12 to 15 lbs bimonthly) post some pictures of larger capacity silver cells? I'm not talking industrial size - but a size suitable for a home refiner.

And can someone tell from looking at the photo why my electrolyte has turned this dark yellow color? What in the world is in there?

Thank you - kadriver


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## samuel-a (Oct 26, 2011)

kadriver said:


> And can someone tell from looking at the photo why my electrolyte has turned this dark yellow color? What in the world is in there?



PGM's most likely...
SnCl is your friend.


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## philddreamer (Oct 26, 2011)

Peter, you can try experimenting with the same set up of half a gallon that GSP help me put together. You might find some information that might help here:
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=50&t=11281

Because, for higher deposition, you'll need to expose more surface area per sq. in. of anode to the cathode. Most cells I've seen posted only have one side facing the cathode. Mine has both sides of the anode facing cathodes thus, doubling the surface area with just one anode. The anodes are 2"x2.5" = 5sq. inches/side x 2 sides = 10 sq. inches; & I use 2 anodes which = 20sq. inches of surface exposed. How much surface area does your cell has?
This could give you an idea of how much you could increase you rate of deposition.

Phil


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## Harold_V (Oct 28, 2011)

kadriver said:


> And can someone tell from looking at the photo why my electrolyte has turned this dark yellow color? What in the world is in there?


My money says it's palladium. A test with DMG or stannous should yield conclusive results. 

With the amount showing in solution, it's entirely possible you are co-depositing some palladium, assuming that's what is determined to be the pollutant. 

I'm quite impressed that there is no copper showing. You've doing an admirable job of cementing your silver. 

Harold


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## kadriver (Oct 28, 2011)

I am going to harvest the silver from this cell later today.

I have no experience with palladium at all.

If palladium is co-depositing, then will it be enought to reduce my silver down below 999?

How will I be able to tell if palladium is co-depositing?

This now has me concerned.

What is DMG?

kadriver


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## philddreamer (Oct 28, 2011)

"How will I be able to tell if palladium is co-depositing?"

Peter, a thought would be to send a 1 oz sample to a fellow member that assays...


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## metatp (Oct 28, 2011)

kadriver said:


> What is DMG?kadriver


dimethylglyoxime

I have some in powder form. I was told (on this forum) that it is best to dissolve it in ethanol. I tried water and I tried ispropyl alcohol, but could only get a small amount dissolve where heated. Once it cooled, it precipitated out. It still worked though. Below is a thread that may help. You need very little so I can give you some of the powder if you like.

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=48&t=6777&p=61924&hilit=+ethanol+dmg#p61924

Regards,
Tom


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## goldenchild (Oct 28, 2011)

kadriver said:


> How will I be able to tell if palladium is co-depositing?kadriver




Simply digest a 1 ounce sample and test with stannous. If there is even a possibility that Pd has co-deposited you will have to process your silver again anyway. If the electrolyte turned that color you should reprocess your silver even if a stannous test shows negative for Pd, or any other PM for that matter. It's obvious there is some type of contaminant. Either way you look at it your best bet would be to make some new anode bars and process with fresh electrolyte.


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## kadriver (Oct 28, 2011)

I'll digest (dissolve 1 oz in nitric) and test with stannous.

Then I will make new electrolyte and anode bars and run it all back through the cell again.

Thanks for the guidance - kadriver


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## philddreamer (Oct 28, 2011)

I agree, the color of the electrolyte is too "strong". Better to make anodes a run again thru the cell. 
I did a test running sterling anodes thru the cell, but the solution turned blue in less than a day, so I just re-melted & ran them thru again in fresh electrolyte. Now, the second anodes looked much cleaner than the first cemented ones, but I don't thick I had .999's. 

Can't you do a stannous test from a drop of the electrolyte?

Phil


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## metatp (Oct 28, 2011)

If there was a little copper in the electrolyte, I don't know if you would have notice the yellow much. The electrolyte would be a little green.


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## kadriver (Oct 28, 2011)

I thought about just doing a test with a drop of the yellow electrolyte.

I will do it tomorrow and post the results.

I am going to make all new clean components and cast the silver crystals into clean anode bars and re-do it all.

This should be some really clean silver when I get done with it.

Thanks - kadriver


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## Harold_V (Oct 29, 2011)

kadriver said:


> If palladium is co-depositing, then will it be enought to reduce my silver down below 999?


It certainly has that potential. 



> How will I be able to tell if palladium is co-depositing?


Wash it well, then use some to make your next batch of electrolyte. If there's palladium present, it will be revealed by DMG. It takes very little to shift the color.



> This now has me concerned.


It should. Not only because you may be producing less than 3 n's, but the contaminant is worth far more money than is the silver. 
Don't despair. You can rerun the crystals without melting. simply pour them to your filter and place a contact on top. Another anode will serve perfectly well. They'll part quite well, leaving behind the palladium (assuming that's what is present). A trace will go in to your electrolyte once again, but it won't co-deposit unless you deplete the silver, or the electrolyte becomes too heavily contaminated. 

I went through this very issue. I dealt with it as I described. No big deal. 



> What is DMG?


Dimethylglyoxime. No refiner should be without it. It is difficult to dissolve in water, but it does dissolve. I used the process found in Hoke's book to make my solution. 

DMG is used to test for palladium, and is also functional for testing for nickel, although the solution tested must be basic. Nickel yields a beautiful pink reaction. It is VERY sensitive, so even minute traces of palladium will respond with a canary yellow precipitate. 

You likely noticed a considerable amount of black slime in your filter after parting the anode, yes? 

Harold


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## kadriver (Oct 29, 2011)

This is all brand new to me. I found the chemical on Ebay:

http://www.ebay.com/itm/Dimethylglyoxime-Reagent-98-25g-/330541245877?pt=LH_DefaultDomain_0&hash=item4cf5cb25b5

Is this the right item, and is that a decent price.

I use stump-out to drop my gold. It is sodium metabisulfite as per the MSDS sheet. I get it at Home Depot for $5 a pound.

Can this chemical - DMG - be found in a similar manner (bought locally under a different name).

I guess I will have to start looking at the other metals, not just gold & silver.

I will get out my copy of Hoke and start reading about these other metals and asking some questions.

Thank you Harold and all the others who have responded to this post for guiding me with this problem.

I'm glad I didn't just wash the silver and let it go.

Thanks to all - kadriver


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## qst42know (Oct 29, 2011)

I bought mine from this seller with no issues. You can up the quantity to reduce the shipping cost.

http://www.ebay.com/itm/Dimethylglyoxime-10-grams-Chugaevs-Reagent-/270826103309?pt=LH_DefaultDomain_0&hash=item3f0e7e620d


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## HAuCl4 (Oct 29, 2011)

A simple way out, if palladium is the contaminant which it seems to be, is this:
When the color gets "too dark" (subjective), get the liquid in a separate bucket, and sprinkle a little zinc dust, just enough to make the solution transparent again. If you sprinkle too much then also silver will cement, get the exact amount by trial and error on a small sample of the solution. After you have done this, the dust in the beaker will be mostly palladium with little silver, and you can put the clear liquid back in the cell. 8)


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## metatp (Oct 29, 2011)

qst42know said:


> I bought mine from this seller with no issues. You can up the quantity to reduce the shipping cost.
> 
> http://www.ebay.com/itm/Dimethylglyoxime-10-grams-Chugaevs-Reagent-/270826103309?pt=LH_DefaultDomain_0&hash=item3f0e7e620d


I bought mine from this guy as well with no issues. I can give you 10g if you want. I don't need all that I have.

Tom


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## kadriver (Oct 29, 2011)

Thanks for those tips on the DGM. I have ordered some.

I got my silver cell all cleaned up and lit-off. I made new electrolyte, but used the same filter bag that was already full of anode bars.

I suspended the filter bag in a container and rinsed it and the anodes with plenty of distilled water and allowed it to drain completely.

The outside of the filter (double bagged actually) looked clean and white.

I am going to save that bottle of yellow electrolyte to experiment with. I want to know how to get the palladium, if any, out of that solution.

Sounds like powdered zinc in the ticket.

When I get the DGM in I will do some tests. I will test it tonight with SnCl.

I am thankful to this forum for the expert guidance that I have recieved with this latest cell contamination.

There is about 500ml of silver crystals. In the past, this volume has yielded about 25 troy ounces of fine silver.

I am going to run it all back through the cell.

Harold said to just put the crystals back into the filter basket. Is there an advantage in processing it this way?

Pouring anode bars seems more convenient. But if the crystals will process faster than bars, then I will run the crystals as they are.

I guess I will save the gas to have to melt and pour the bars.

Thanks for looking - kadriver


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## philddreamer (Oct 29, 2011)

I precipitated Ag, Pd & other metals from my silver nitrate with SMB once.
Your Ag nitrate solution might have only Pd contamination, @ least we hope, than the one I had, so maybe test a bit with SMB. 

Question... How many onces did you really run thru that solution?


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## kadriver (Oct 30, 2011)

That yellow electrolyte had about 75 troy ounces through it. 

I tested the solution with stannous chloride tonight and it was positive. But for what?

I have never seen stannous chloride react with anything other than AuCl.

I know there can't be any gold dissolved in the electrolyte.

Maybe this is palladium. This is my first experience with that metal if it is.

How did palladium get in with my silver - I cement 100% of my silver anode bars.

I guess it must be carried by the silver - and then it cements out with the silver?

I dissolved some more 925 and older sterling dishes tonight - about 800 grams.

The resulting silver nitrate solution was quite green looking - and the silver cemented out real fine - the finest powder I have ever seen - almost like real fine mud.

Just goes to show how much more I have to learn.

kadriver


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## Palladium (Oct 30, 2011)

Do you heat your solution when you drop the silver with copper?


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## Harold_V (Oct 30, 2011)

If any of your silver was used for inquartation, pretty good chance you picked up some palladium. When it's present, you'll find the solution leans towards green---and lightens to blue when all of the palladium has been cemented. The cemented palladium will discolor your silver, making it appear darker, even towards black, assuming you have enough present. 

On that note, when ever you cement silver, if the barren solution is not blue, test with stannous chloride. The platinum metals are slow to cement, coming down only when all of the silver has been cemented. You can expect platinum in your silver nitrate solution, along with palladium, considering platinum will dissolve in nitric to some degree, when alloyed with silver. 

The test with stannous chloride can resemble gold to some degree, depending on many variables, but you won't get a purple stain. The general reaction is anything from green through blue, however. It's a bit of a chameleon. That's why you should test with DMG-----it is conclusive, leaving you with no questions. 

Don't be surprised by the presence of palladium in your silver. It's just a matter of time until you encounter some------as well as platinum. For that reason, you should concentrate your studying on those metals. They're a great retirement plan. Set them aside for that day. 

Harold


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## kadriver (Oct 30, 2011)

I checked on the silver that I dissolved last night. The silver had quit cementing, just as you described. There was a darker coating of material on the copper coils that I used to cement the silver with.

I took a drop of the solution and tested with stannous chloride. I was surprised to see a reaction. It has really got me thinking now.

I have been so focused on the gold and silver, that I have neglected to even consider that these other metals are present in some of these solutions.

I have seen green silver nitrate in the past, but it never sunk in to investigate what else might be in the solution besides silver.

This silver cell contamination event has opened my eyes.

I am now seeing other metals everywhere it seems!

I took down my copy of Hoke's book and literally wiped the dust off of it last night. I am going to devote my time to study of the other metals and how to get them out.

But for now, what should I do about this silver nitrate solution that I have now?

It appears that most of the silver has cememted out.

The copper coils that I use were still pretty beafy, and they were coated with the darker material.

Should I add some HCl to get the rest of the silver to precipitate out as silver chloride, then try to cement the platinum or palladium that is still in the solution.

Here I am, clueless all over again. Refining has a way of doing that to a newbie.

Thank you - kadriver


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## kadriver (Oct 30, 2011)

Palladium:

I did not heat the solution. In fact, I was getting heat building up as the silver was cementing out.

I was even getting some fumes from the cementing.

I finally added some ice made from distilled water to get it to cool down.

I keep two or three trays of ice made from distilled water for dropping gold. I had a boil over while dropping gold a while back.

Now I add ice and place the container into a pyrex baking dish to catch any liquid if it does boil over.

kadriver


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## HAuCl4 (Oct 30, 2011)

freechemist said:


> You can forget about DMSO and spend your 18.2 Euro on different ways. DMG dissolves easily in aqueous NaOH. Use 2 moles of NaOH per mole of DMG and sufficient water to make up a solution of about 1 mole/lt NaOH. Adding this alkaline solution of DMG slowly to the nitrate solution will precipitate Pd selectively and quantitatively, without precipitation of Ni, provided the mixture will still remain acidic after addition of the alkaline precipitation agent. This can be assured by beforehand addition of an equimolar amount of nitric acid (2 moles per mole of DMG) to the nitrate
> solution.


http://goldrefiningforum.com/phpBB3/viewtopic.php?f=51&t=9058&hilit=freechemist+DMG+NaOH

I suggest you read this post and this thread and understand it well. 8)

If you already purchased DMG, then use it to recover very clean palladium from your solution, and then recycle the now clear silver nitrate into your silver cell. That's probably better than using zinc. All in all there isn't much palladium to recover, and DMG will get it all and in very pure form without further processing.IMHO. 8)


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## kadriver (Oct 30, 2011)

HAuCl4:

Thanks. I will study it. I am not a chemist at all.

I have been reading Hoke's book on testing solutions for all metals in solution. I completely ignored this section because I was concentrating on gold & silver only.

The only one that I am familiar with is stannous chloride. And I have only used it to test for dissolved gold - until last night.

I am working on getting all the items needed for making the test and standard solutions talked about in Hoke. Then I will do the experiments as outlined in that section. I think it is Chapter IV.

I'm sure it will reveal how I need to go about getting the palladium out - if it is palladium.

I guess i will save the silver nitrate solution from last night and do some tests to see what is in there with the silver.

I chuckled when I read the part about beginners having worthless and useless unlabeled solutions sitting around. I am guilty.

Thank you - kadriver


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## philddreamer (Oct 30, 2011)

Peter wrote:
"That yellow electrolyte had about 75 troy ounces through it. 
I tested the solution with stannous chloride tonight and it was positive. But for what?
I have never seen stannous chloride react with anything other than AuCl.
I know there can't be any gold dissolved in the electrolyte..."

To me, it seems you ran too much material thru 1 litre of electrolyte; I undestood that as soon as the solution starts getting "dark", which is a sign of contamination, that it should be changed, but our experts will have the final word on that.

Also, the stannous test was +, but what was the color? 

Palladium wrote:
"Do you heat your solution when you drop the silver with copper?"

I read the advised of the experts of heating the solution, but like Peter, my solution is loaded with silver & it gets hot fast when I start cementing. If I preheat the solution, wouldn't I run the risk off boil over? My question, the hotter the better for cementing?

Thanks Harold for the detailed explantion, excellent! I will be buying DMG, because like Peter, I want to master this silver refining process for the reasons you mentioned.

Thanks HAuCl4 for pointing the topic:
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=51&t=9058&hilit=freechemist+DMG+NaOH

Phil


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## samuel-a (Oct 30, 2011)

philddreamer said:


> I read the advised of the experts of heating the solution, but like Peter, my solution is loaded with silver & it gets hot fast when I start cementing. If I preheat the solution, wouldn't I run the risk off boil over? My question, the hotter the better for cementing?



Heat = time saver.

You would get same results after a week in a cold solution or a day in a hot one.
You can always fill the jug 1/2 way through so no spills occur.

I usually start the heat only after the majority of the silver had cemented.


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## philddreamer (Oct 30, 2011)

Thanks Samuel, now I have a starting point for when I can start heating.

Phil


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## Palladium (Oct 30, 2011)

I tried it both ways and believe heating before percipitaion is the way to go for me. It comes down fast and fine which makes for easy clean up.


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## Harold_V (Oct 31, 2011)

Key to recovery of all of the silver and what ever platinum metals are included is to present a large surface area of copper to the solution. I don't recall ever heating for cementation, and that includes solutions that contained a rather generous portion of platinum and palladium. I processed a decent amount of dental gold, so my silver was almost always laden with them. 

When your solution tests positive, simply allow it to stand longer. Once the silver is down, it, too, helps cement the higher values. In the end, you will achieve a full recovery, to the point where the solution is blue, and there are no detectable signs of other values. Also, after all has been cemented, stir the lot, to liberate silver nitrate that was dragged down and is isolated from contact with copper. 

I generally allowed 24 hours for cementation and rarely needed more. I also had a large amount of copper in use at all times, so I could extract the values in what I considered a reasonable time. I used to melt copper and pour ingots that would be the equal of 100 ounce silver bars. I used the same mold for both purposes. I'd use two or more of those ingots, along with smaller pieces of copper that could be extracted after the silver was down. Any copper wire that I used was melted and poured as an ingot, to avoid the risk of residual copper being left behind. 

On the subject of using DMG to extract palladium, I don't agree. It's costly, and creates a huge volume of palladium that will be difficult to handle. In fact, that's one of the reasons it's so useful as a testing solution. Small traces of palladium will yield a very visible precipitant, so the test is very sensitive. You're far better served to cement the palladium along with the silver and extract it from the slimes in the next parting. If you keep the palladium content low in your silver, it won't co-deposit with the crystals. Armed with that idea, don't reuse cemented silver for inquartation unless there is no palladium involved. If it accumulates too highly in your cement silver, parting will become troublesome, with co-deposition pretty much assured. Been there, done that.

Harold


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## kadriver (Oct 31, 2011)

Harold_V said:


> You're far better served to cement the palladium along with the silver and extract it from the slimes in the next parting.
> 
> Harold



I think I get it: the key to getting the other metals is to cement them all out with the silver. Wash the cemented silver as usual. Then dry and cast into anode bars. Then recover the other metals from the slimes in the anode basket.

I was wondering how I was going to get the other metals out of the spent electrolyte.

Should I just cement the silver from the dark yellow spent electrolyte with copper as usual? Will the other metals, if any, cement out with the silver?

The color of the solution in my cell did not get dark until this last batch. The previous batch of silver that I ran through the cell was processed in the same electrolyte but it was far lighter in color when I harvested the silver crystals.

That is why I posted it on the forum. I had never seen dark yellow contamination before. Sometimes green, but mostly blue.

I use copper wire coiled up and suspended in the silver nitrate with a string hung from a glass stirring rod. I monitor it closely to ensure that the copper wire does not get too thin and start dropping bits of copper into the silver. When the coil starts to get thin, I put in a new one. When I am sure that most of the silver is cemented, I put in a fresh coil or two and let it set overnight.

I have a 3 liter jar full of partially used copper wire coils. I have been melting them in a large dish to make a disk of copper that I can use to suspend in the silver nitrate.

I would like to get a nice furnace and melt the copper properly, then pour into bars like Harold talked about.

I will keep a close eye on this cell to see if I get any more contamination. So far it has turned a very pale yellow and the silver crystals are growing nicely.

The stannous test on that electrolyte produced a brownish color. I have no idea what that means.

Tomorrow I am going to make a fresh batch of stannous chloride and re-do the test. I will take some pictures and post them.

By the way, I processed some more silver last night. As I stated earlier, the silver nitrate was green. This batch was very unusual.

First, the cemeted silver was very fine - like pluff mud. It actually bonded together in the funnel in a large cake and I had to pry it out with a spoon.

Also, I used twice as much water than usual to get all the color out of the rinse. I tested the rinse water with HCl and there was silver chloride forming after about 1 and 1/2 gallons of distilled water had been through the silver. I use boiling distilled water to rinse the silver. 

The resulting silver powder appeared darker than usual and much heavier per unit of volume than usual. It usually takes three spoons to get to 48 grams (the size of my anode bars). But this batch only took two spoons to get 48 grams.

The resulting anode bars looked a bit unusual. They were rouogh in appearance and frosty looking. My cemented silver anode bars usually look about as good as the fine silver bars.

I am thinking that I may have some other metals in the batch of silver. I did a stannous test on the silver nitrate last night and got a reaction - but I cannot remember the color. I have some of it left. I will do another test tomorrow with fresh stannous chloride.

If not for this forum, I would be making mistake after mistake. Learning by trial and error. Thanks to all for your input .

kadriver


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## Harold_V (Oct 31, 2011)

kadriver said:


> I think I get it: the key to getting the other metals is to cement them all out with the silver. Wash the cemented silver as usual. Then dry and cast into anode bars. Then recover the other metals from the slimes in the anode basket.


Correct. That's the entire purpose of the silver cell---to remove traces of impurities---of all types. Some go in to solution, while others accumulate in the slimes. 



> I was wondering how I was going to get the other metals out of the spent electrolyte.
> 
> Should I just cement the silver from the dark yellow spent electrolyte with copper as usual? Will the other metals, if any, cement out with the silver?


That's exactly how I'd do it. At this point you don't have a lot of palladium in solution. That's obvious by the color. Palladium, when concentrated, will be dark coffee in color. The slight amount present won't create any issue for the next refining, and will, for the most part, report in the slimes. Expect traces to go in to solution, considering palladium readily dissolves in nitric. Traces won't be troublesome. Just keep watch on the color. 

I'm curious. What have you done with your slimes up to this point? From your description of previous solutions, it sounds to me like you've recovered some platinum and/or palladium. If your electrolyte had turned green, fair chance that's why. My electrolyte was never blue---always tinted green when it was exchanged. That was due to my constantly handling palladium, and the fact that my silver always had traces of copper. I was impressed that yours did not. 

Harold


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## kadriver (Oct 31, 2011)

Harold:

Since I have been refining silver I have not been processing the slimes in the anode baskets for other metals.

The last couple of anode baskets are sitting at my shop still full of the material that was left from the refining. I have started making up a new basket and filter when ever I harvest the silver crystals. The cost is minimal and it gives me a little peace of mind.

I always double bag using one filter fit inside of another. I ensure that there are no seams or splits in the filter itself to guarantee none of the wastes in that filter bag make it into the cell with the pure silver.

Before that, I used to re-use the anode basket filter bags. I would remove the filter and place it on the inside of a 2 liter beaker. It would stick to the side of the beaker and then I used a squirt bottle to rinse all the slimes off the filter and into the bottom of the beaker - then re-use the filter.

Since I was only concerned with the silver, I would treat the slimes from the 2 liter beaker with nitric acid, then filter out the solids and save the remaining silver nitrate for cementing.

I think I just stuck the filter papers with the solids in my gold filter paper bag. I was quite unsure what to do with the solids that filtered out of the silver nitrate. I had tunnel vision - only gold & silver mattered to me.

I may have some values in those unprocessed filter baskets, and from the filter papers.

As a newcomer to refining, I was overwhelmed with just getting some good product out. Since I was learning, and still am, I wanted to try to keep it simple. Because of this (and I suppose a little lack of diligence) I completely ignored trying to recover any of the other metals.

But now things have changed for me. I have always said that the main ingredient in being good at ANYTHING, is the desire to do so. Before this contamination incident with my silver cell, I lacked that key ingredient.

I feel as though I am getting ready to open new doors in refining. I now have a strong desire to get at these other metals and start processing them. I can see where this could provide a big benefit - not only can I get the gold & silver, but I can start accumulating the other precious metals as well.

I am going over to my shop later today. I will re-test the yellow electrolyte with fresh stannous chloride. I will also test the remaining silver nitrate I spoke of in an earlier post. then I will add the two liquids together and begin cementing with copper.

I will post photos of these test results.

Thanks to all - kadriver


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## Rodthrower18 (Oct 31, 2011)

Kadriver, 


I can't wait to see these photos! I am learning so much from so many of the exchanges that everyone has around here. Most of the questions that I THINK I'm coming up with are getting answered somewhere on the forum or with the help of my dear friend mr search bar.

Good luck to all


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## goldenchild (Nov 1, 2011)

kadriver said:


> The resulting anode bars looked a bit unusual. They were rouogh in appearance and frosty looking. My cemented silver anode bars usually look about as good as the fine silver bars.
> 
> I am thinking that I may have some other metals in the batch of silver. I did a stannous test on the silver nitrate last night and got a reaction - but I cannot remember the color. I have some of it left. I will do another test tomorrow with fresh stannous chloride.
> 
> kadriver



Could be due somewhat to contanmination but it also looks like the metal was over heated causing boiling.



Harold_V said:


> Key to recovery of all of the silver and what ever platinum metals are included is to present a large surface area of copper to the solution. I don't recall ever heating for cementation, and that includes solutions that contained a rather generous portion of platinum and palladium. I processed a decent amount of dental gold, so my silver was almost always laden with them.
> 
> Harold



This has me thinking. Just how common is it to get Pd contamination in silver and vice versa. I don't think it is very common at all unless you are processing dental scrap. Isn't Pd used in place of silver in karated jewelry which is rare in itself?


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## kadriver (Nov 1, 2011)

I do not know how this contamination got in there.

Here is the test I did with fresh stannous chloride solution this evening.

The four photos are a series of pictures about 2 seconds apart as I dropped the stannous chloride onto the sample of spent electrolye (the dark yellow liquid from my silver cell).

It obviously tested positive for something. I do not know what this test indicates. It turned a brown color very rapidly in about 5 seconds. 

Then it stopped and remained as pictured.

The silver nitrate showed a very faint yellow color.

I tested this same silver nitrate solution two night ago and it was much darker that the test result from tonight.

I do not know what it is. I am hoping that the forum members can tell what it might be from looking at the photos.

This is all very exciting - like starting all over again.

I feel a bit overwhelmed because i am not certain what I should do next.

I probably need to study some more and take a break from it for a while.

The nice thing about it is that it will still be there for me tomorrow. It isn't going anywhere.

Thanks for looking

kadriver


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## kadriver (Nov 1, 2011)

Here is what the cell looks like tonight.

It is starting to get yellow again.

The crystals are growing nicely.

I may have to change the electrolyte when I take the silver out.

By the way, does anyone see a problem with leaving that glass rod in the cell when it is operating?

kadriver


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## Harold_V (Nov 2, 2011)

kadriver said:


> I do not know what it is. I am hoping that the forum members can tell what it might be from looking at the photos.


Palladium tends to yield a green/blue color reaction, but that's testing a chloride solution. It's entirely possible the results you see are due to a nitrate solution, especially considering there's silver present. Dunno! One thing I'll mention, though---there may be times when you get a reaction from palladium that makes you question of you have gold present (there won't be a purple stain, in spite of a dark reaction, much like the one you got). I do not understand all the variables that cause the tests to vary as they do. 

One thing to consider is that platinum can yield a dark brown reaction, but that's when it's highly concentrated. How you'd get platinum in solution with a silver cell I can't say. To my knowledge, that doesn't happen. 

In my opinion, leaving the glass rod in the cell does no harm. 

Harold


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## Geo (Nov 2, 2011)

could you have mixed a white gold ring in with your silver rings? they use Pt in white gold,dont they? i dont know, just a thought.


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## nickvc (Nov 2, 2011)

As a note on the appearance of platinum,rhodium or palladium in your silver it can be because the manufacturers are now producing silver items made to look like white gold, cost of metals, it is far from uncommon these days for items to be plated with any of the mentioned metals to give it that white appearance and palladium was used as a cheaper substitute for rhodium.


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## kadriver (Nov 18, 2011)

I cemented the silver from the dark yellow electrolyte this evening.

The silver cementing out appeared much draker than I am used to seeing.

The silver in the container to the right is from freshly digested sterling and 925 jewelry.

The container in the middle is the dark yellow electrolyte mixed with some dissolved sterling and 925 material.

Also, before I put the dark yellow solution into the container to cement out the silver, I did another stannous chloride test.

This time it turned a violet to purple color (see photo).

I am still studying Hoke on how to identify metals in solution.

I got my DMG today, but I have not had a chance to make some test solution. I did save about 2ml of the dark yellow electrolyte for later testing with the DMG.

Thanks - kadriver


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## kadriver (Nov 18, 2011)

Here is the last stannous chloride test that I did tonight from the dark yellow electrolyte.

The color is violet or purple - can this be gold?


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## Harold_V (Nov 19, 2011)

kadriver said:


> Here is the last stannous chloride test that I did tonight from the dark yellow electrolyte.
> 
> The color is violet or purple - can this be gold?


No. What you're seeing is silver (photosensitive). It is unreasonable to expect gold in a nitrate solution. That doesn't happen. 

The color reaction when you apply the drop of stannous chloride is the color to read. 

You can confirm it's palladium with DMG---you'll get a distinct yellow precipitate. Where you have a lot of silver in solution along with palladium, it may pay to add a drop of HCl to the test before using DMG (test in a spot plate cavity). That will precipitate the silver as silver chloride. Test the resulting solution by dragging a drop from one cavity to another with a glass rod. 

I highly recommend you get in the habit of testing with a spot plate. You are limited with cotton swabs. So much so that I NEVER used them. No need. They're a waste of resources and complicate the recovery of the miniscule amounts of values lost in testing (washed to the stock pot with ease from a spot plate). 

Harold


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## kadriver (Nov 19, 2011)

I will order a spot plate today.

Also, I will make some DMG test solution and test the dark yellow silver nitrate electrolyte - then post the results.

I ended up mixing all the silver together and washing with boiling distilled water.

I am curious to see what will be left in the slimes of the anode basket after this batch of silver is put through the cell.

I added some nitric acid to the anode basket slimes from some earlier cell clean outs.

Using the process Harold posted, I am going to process these slimes and post what I recover from them.

This will be my first time processing anode basket slimes. 

Thank you - kadriver


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## kadriver (Nov 19, 2011)

Here is a picture of the spot plate I just purchased on Ebay for $7.00 - I bought two of them.

It is made of glazed ceramic, the back is left unglazed.

It measures about 3.5 inches by 4.5 inches.

This should serve well to test solutions for dissolved metals.

kadriver


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## kadriver (Nov 20, 2011)

I made up a batch of DMG test solution.

I put abour 1/2 gram in a small flask, added some distilled water and then boiled.

It all dissolved, then some crystals formed after it cooled a bit. I must filter out the crystals.

Before the crystals formed I was able to do the test on the dark yellow silver cell electrolyte.

I divided the amount I saved equally between two test tubes. Then added DMG solution to one. DMG test is on the left in the photo.

Does this test indicated a positive result for the presence of palladium? There was a light pricipitate in the solution - according to my Hoke, this is confirmation of palladium.

kadriver


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## Harold_V (Nov 20, 2011)

kadriver said:


> Here is a picture of the spot plate I just purchased on Ebay for $7.00 - I bought two of them.


Well done! They will serve your needs perfectly. 

In regards to your DMG test, if you introduced enough test solution, when the resulting material settles, the solution should be clear of color. The precipitant is canary yellow. Might not hurt to test with stannous chloride, too. If nothing else, it's a good exercise and learning experience. 

Harold


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## adam_mizer (Nov 27, 2011)

This thread is excellent!

If it were not for several of the answers and tests as well as the natures of palladium and platinum metals in solutions I would have not bothered to retest some of my disgarded wastes.
This thread put me on a roll and certain of my disgarded wastes are dropping PM's right now.

Keep up the good work and questions/answers as they are very inspiring to further develope my skills.
Thank you kadriver for your informative process inquisitive nature show and tell and the answers that follow along from everyone. 

John


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## g_axelsson (Oct 3, 2013)

Great reading! This thread needs to be bumped!

I'm also curious, kadriver, was it palladium in your electrolyte? Did the liquid in the test tube lose it's color when the precipitate settled? What other metals did you find in your slimes?

Maybe you wrote another thread about that... if I find one I'll add a link here.

Göran


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## Recyclotrops (Mar 1, 2014)

I too am hungry for more info about how this all worked out. Please update this thread if you get the chance kadriver.


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## kadriver (Mar 7, 2014)

g_axelsson said:


> Great reading! This thread needs to be bumped!
> 
> I'm also curious, kadriver, was it palladium in your electrolyte? Did the liquid in the test tube lose it's color when the precipitate settled? What other metals did you find in your slimes?
> 
> ...



The material in the electrolyte was palladium. It's been a while but I think I put the used electrolyte in a 4 liter beaker and added DMG that had been dissolved in boiling distilled water.

The DMG precipitated the palladium in the form of a bright yellow material that I was able to filter out easily via gravity filtration through a regular glass funnel using a #1 Whatman 185mm filter paper.

The color of the liquid was green going into the funnel (probably from the suspended yellow palladium precipitation), and the filtrate (liquid in the receiving container below the funnel) was a vivid blue color.

I rinsed the palladium precipitate with cold distilled water while it was still in the funnel to get out as much silver nitrate and copper nitrate as possible.

Then I removed the filter paper that contained the bright yellow precipitate and placed it on some paper towels.

I have a stack of these filters each with palladium precipitate and some day in the future I'm going to refine the palladium.

kadriver

Edited once to add a thread reference

Here is a post that has a video that shows how I removed the dissolved palladium from the silver cell electrolyte:

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=50&t=19004&p=192260&hilit=Dissolved+Palladium+from+Electrolyte#p192260


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## g_axelsson (Mar 7, 2014)

Thanks! Very interesting!

Göran


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## kadriver (Mar 8, 2014)

If I remember correctly, this electrolyte turned green instead of the usual blue color. The blue is from dissolved copper.

In this particular case I had added some nitric acid to the cell because crystal growth (and consumption of silver shot in the anode basket) had slowed way down. I was trying to increase the silver nitrate concentration by adding nitric acid to dissolve some of the silver crystal that had formed in the cell electrolyte.

The next day after adding the acid I noticed that the electrolyte had turned green instead of the usual blue color that I was used to seeing.

I concluded that the nitric acid that I had added the day before had dissolved some palladium that was trapped in the anode basket. I do not know if this conclusion is correct or not, but I have recovered palladium from my silver cell slimes by dissolving the slimes in dilute nitric acid.

Small amounts of palladium dissolved in dilute nitric acid will produce a yellow colored solution. Copper dissolved in nitric will produce a blue colored solution.

If one mixes a blue solution with a yellow solution the result is a green solution.

Since that time I have never added nitric acid to my silver cell electrolyte again. To increase the concentration of the silver nitrate I dissolve some pure silver crystal that I keep in reserve, gently evaporate off some of the liquid, then add that solution to my silver cell electrolyte.

I think I read on the forum somewhere that there are specific pH ranges for silver cell electrolyte. If these ranges are maintained in the cell then the palladium won't dissolve from the anode basket.

But I think a small amount of palladium will get in the electrolyte no matter what precautions are taken.

kadriver


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