# Problems Cementing Silver with Lye



## chawimac (Nov 10, 2012)

I am having problems with AgCl all over the place and wanted some advice/help as to the many possible things I may be doing wrong.

For months now I have been dropping silver out of my AgCl with copper. At first it suited my needs, but now I use 35 pounds of copper every week and am sick of the days processing, filtering, fumes, etc.. etc.. etc..

I decided to try a batch with the table salt/lye/sugar process. It went wonderful and got 35 grams of .99 silver. I was sold! As soon as I scaled up, my luck changed. Here is what I did:

I took a 5 gallon bucket full of Silver Cloride and dumped about 4 pounds of salt into it. Ordinary cheap salt we get in bags. As expected I get a white precipitate. I filtered the precipitate and washed it with water. The remaining water I added more salt to be sure we got all the silver out. The salt just piled on the bottom of the bucket. Good so far right?

I took the wet precipitate which is of course silver in an odd form, and proceeded to add lye in flakes I get from a chemical supply. Sure enough things start to turn black and brown. There is heat from the reaction but not anywhere near what I have seen on youtube where this stuff actually boils. I added a bunch of lye and made sure there was no more white residues in the silver from the first step in this process. As far as I can see the process is going in the right direction and the lye has done its job. I proceeded to filter the solution and wash it several times to remove excess lye I might have added.

I am posting some pics of what this all looks like.

So anyways, the next step is to add syrup. I boiled water and made a heavy simple syrup using ordinary cheap cane sugar. I then proceed to add the syrup to my gray silver, hoping for a chemical reaction as the first time I tried this. No heat. Nothing. What gives??? As a disclaimer, the steps were not performed the same day. Why is there no reaction to the sugar? I am expecting a heavy boil.

Any thoughts?


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## chawimac (Nov 11, 2012)

Below is a picture of the silver produced after I filter the material that was processed with syrup. The material was filtered and washed, then gently dried on a hot plate.

When you try to melt this stuff on an induction oven, it is impossible. When you try to melt in a gas kiln, it helps if there already is some molten metal in the crucible. If you use a propane/oxy torch, it eventually melts. Does using some type of flux help here? What am I doing wrong?


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## acpeacemaker (Nov 11, 2012)

Out of curiosity have you read Hoke? Not just watched youtube? Your first part of the post is confusing. You say your adding tons of copper to Agcl? Why? You state you got 35 grams of .99 silver from your first go? 4 lbs of salt? How much Acgl was expected? Your supposed to add the sugar during the heated reaction.











Edit; computer has a mind of its own


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## chawimac (Nov 11, 2012)

Just some eye candy for some of the NOOBs (like me!) of some material I processed today. Everything I know I learned from this forum, so I am very thankful to you all for your help and the many wonderful posts that have helped me.


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## chawimac (Nov 11, 2012)

acpeacemaker said:


> Out of curiosity have you read Hoke? Not just watched youtube? Your first part of the post is confusing. You say your adding tons of copper to Agcl? Why? You state you got 35 grams of .99 silver from your first go? 4 lbs of salt? How much Acgl was expected? Your supposed to add the sugar during the heated reaction.



Yeah I never got around to reading all of Hoke's book. I would get excited after a chapter and want to practice what I was reading. Laziness I guess but I got what I needed, almost.

I just noticed what you are saying about AgCl. You are right, it isn't AgCl. It is Silver Nitrate (???) as I dissolve base metals with Nitric Acid and Distilled Water. I inquart all my gold.

My first try was a 1 liter beaker. After that I scaled to 5 gallon buckets. And though this sounds idiotic I have no idea how much silver is expected. I just process so much, I check at the end of the week that I have more than what I started with.

In my defense, youtube is a great tool. Reading some of these processes is not enough. Some of these reactions are impossible to explain in words, and take experience to truly understand the reactions and spot and resolve problems.


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## butcher (Nov 11, 2012)

Personally I would rather use copper to cement silver from the silver nitrate, it is a much easier process than dealing with silver chloride, I would also recover the copper from the copper nitrate solution and reuse it, as much as possible, cementing silver using copper it is so much easier, less chance for trouble, no need to convert before melting, and less loss of silver.

I mess with silver chloride more than I like to , but try to avoid it, as much as possible, it always seems such a pain, (although I like seeing that white fluffy looking powders for some reason, and like seeing it convert to silver in the sun light).

As far as your silver chloride conversion, I did not hear anything about stirring, actually stirring is a mild word you need power blending, chopping and stirring, then more stirring. 
I do not work in as large a batch as you have, I use a household blender, silver chloride need mixing very well to covert all of it, heating some can help if the reaction does not generate enough heat on its own.

I follow GSP's recipe, approximately:
1-ounce silver (41.5g AgCl)
20g NaOH
13.3ml Karo light corn syrup
133ml H2O
Stir the snot out of it.
Heat if needed
If silver chloride has base metals or impurities the conversion does not seem to work as well.

Other silver chloride conversion methods, (I like), the clean Iron metal and dilute sulfuric acid, stirring well so all silver comes into contact with iron, so that all of the silver chloride is converted to silver.

I have never tried the aluminum and HCl to convert silver chloride, (I guess because I hate dealing with aluminum chloride waste).

Hokes read it, there are hidden treasures in this book, many of which you will find very helpful.
GSP's Book has been valuable to me, and I thought it was worth every penny to get his work and experience on paper (I had to print it out), also reading His post tons of information can be gained (although sometimes his math skills can make my head dizzy).

Your melting problem may be due to several things, but not having a complete conversion comes to my mind.

Edit to correct Anion


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## Geo (Nov 11, 2012)

what you are doing is producing silver nitrate. i would recommend that you continue using copper to cement the silver out of solution even if you are doing a five gallon bucket at a time. by converting the silver nitrate to silver chloride with salt, you are adding three more chemicals to the silver and more than tripling the work. if you use clean copper, your cemented silver should be pure enough to inquart gold with no problem. its simple and quick, cement and melt. 

did you rinse all the salt with boiling water after you converted the silver to AgCl and before you added the lye? there are steps to take and it sounds like you may have skipped a couple. 

mill what you have to a fine powder and give it a good boil in water to remove all of the sodium and see if the melt goes any better. too, excess salt may have interfered in the conversion of AgCl to silver oxide.


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## chawimac (Nov 11, 2012)

Geo said:


> what you are doing is producing silver nitrate. i would recommend that you continue using copper to cement the silver out of solution even if you are doing a five gallon bucket at a time. by converting the silver nitrate to silver chloride with salt, you are adding three more chemicals to the silver and more than tripling the work. if you use clean copper, your cemented silver should be pure enough to inquart gold with no problem. its simple and quick, cement and melt.
> 
> did you rinse all the salt with boiling water after you converted the silver to AgCl and before you added the lye? there are steps to take and it sounds like you may have skipped a couple.
> 
> mill what you have to a fine powder and give it a good boil in water to remove all of the sodium and see if the melt goes any better. too, excess salt may have interfered in the conversion of AgCl to silver oxide.



Here are the issues I have with copper: the fumes are almost worse than when digesting the silver with nitric, or the gold in AR. I use a 55 gallon plastic bucket and leave it outside covered. You can smell this stuff a block away sometimes. I feel really irresponsible about this. I use copper wire or whatever I can find at the local scrap yard, this sometimes is a challenge as I buy so much copper it is difficult to get the good stuff. If I use copper plate or tubing, the process runs OK, but wire is a mess. The wire seems to get clogged up with silver and never fully digests. I end up with slivers of copper that contaminate my process and is a pain or impossible to filter out. A barrel takes 3 or 4 days to process, and its impossible to be there (time, fumes) to make sure digestion is going well. You end up with a crunchy copper/silver mess. When I did this with a 1,000ML beaker it was cool, not so much now. As far as recovering the copper, I tried to do it with Iron or Aluminum which worked to a certain degree. Try filtering all this stuff and melting it down. It is such a fine material that it takes days to process. After the cost to melt and time to filter I gave up on recovering the Copper. If I had an industrial filter press would be great, but of course I don't so the job is next to impossible.

I rinsed the salt out of the AgCl, though perhaps not enough. I will try to clean it better and using less salt to begin with.


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## chawimac (Nov 11, 2012)

butcher said:


> Personally I would rather use copper to cement silver from the silver chloride, it is a much easier process than dealing with silver chloride, I would also recover the copper from the copper nitrate solution and reuse it, as much as possible, cementing silver using copper it is so much easier, less chance for trouble, no need to convert before melting, and less loss of silver.
> 
> I mess with silver chloride more than I like to , but try to avoid it, as much as possible, it always seems such a pain, (although I like seeing that white fluffy looking powders for some reason, and like seeing it convert to silver in the sun light).
> 
> ...




Thnx for the great advice and details. I agree with the copper process, its just a convenience thing for me as this seems like there is far more work involved with the copper process. How would you guys do it on a larger scale?

I will get a paint mixer today and try that. Will post tonight see how it goes. I have 300 gallons of Silver Nitrate to process and its driving me crazy!!!


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## g_axelsson (Nov 11, 2012)

If you get a lot of fumes when cementing on copper then you haven't used up your acid while inquarting.
The cementation process doesn't emit any fumes by itself. It comes from copper being dissolved by the nitric acid.

/Göran


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## nickvc (Nov 11, 2012)

I tried to post earlier but lost it when my iPad locked and I had to re start it. My opinion is the same as Butchers I would avoid creating silver chloride if you can. I think that perhaps you are using too much nitric and or that your not diluting it if you are getting loads of fumes when you cement the silver back out. I assume your using heat with your dissolution of the silver and base metals but if you aren't that may be part of the problem the same may be true if your using strong undiluted nitric, there are formulas for working out how much nitric you need. As with all acid dissolutions the temptation is to over use them, with hydrochloric that's not too much of a problem but with nitric it is, nitric is also relatively expensive so using only what you need makes commercial sense. I can understand your need to refine the gold quickly especially in the volumes your doing but allow the acids to do their work and only add more if all the reaction stops and then only in small increments, if your really in a hurry calculate how much nitric is needed and use less,cool,decant carefully and restart the reaction again with fresh diluted acid but again don't use too much.
When you then cement your silver using copper the fumes should be minimal and your copper usage should reduce, if as you say you are using so much then perhaps cementing the copper back out using steel, decant filter and wash and use that powder to start the cementation but finish using clean copper.
As your processing karat scrap you need to remember that the silver you use to inquart with also acts as a carrier for the PGMs which will be recovered amongst your silver and which will need to be put through a silver cell at some point to recover them in the slimes, any gold in your silver will also be recovered. If your not using a cell I hope your testing all your solutions with stannous and keeping a stockpot for any values your finding.
I agree with Butcher you need to read Hoke and understand what she teaches you could be making much more money by understanding her teachings and also making your own work easier.


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## goldsilverpro (Nov 11, 2012)

Just some thoughts.

COPPER. Filter the diluted solution before adding the copper. 35 pounds of copper will theoretically cement 119 pounds (1735 tr.oz.) of silver, assuming there is little or no free nitric after dissolving the silver. If your actual numbers aren't within about 5-10% of this, you are using too much nitric and the extra nitric dissolving copper is the main source of the fumes. You need to contact several scrap yards to shop around for better copper. The best is clean bus bar - no solder - no tin plating. Look for bus bar at least 1/4" thick and 2" wide. This will produce fewer slivers and less contamination. Wire is the absolute worst, as you well know. The cemented silver intermingles with the copper slivers. Copper tubing is in between. You might get slivers as it eats through but not nearly as much as the wire. Instead of a 55 gallon drum, I think I would prefer a bunch of buckets. They're much easier to handle. I would cut the bus bars just short enough to allow a lid to be put on the bucket, but still be long enough to stick out of the solution, so they can be easily removed. The more copper surface area, the faster it will cement. I would probably use about 6-8 pieces of bus bar per bucket. I stirred it occasionally using one of the bus bar pieces. During warmer weather, it rarely took longer than overnight to finish. 

SILVER CHLORIDE. Before adding anything, I would filter the diluted silver nitrate solution to remove any dirt. If you use salt (NaCl), I would dissolve it before adding it. A pound of pure salt will theoretically dissolve in about 1300ml of water and this will precipitate about 27 oz of silver, as AgCl. One liter of 31% muriatic acid (HCl) will precipitate about 34 oz of silver as AgCl. After dropping the AgCl and allowing it to settle, it should be siphoned, filtered, and rinsed well (to remove the acid) as soon as possible. The longer it sits around, the harder it is to filter. Once filtered, never let it dry. While damp, transfer it to the conversion tank and convert it as soon as possible.

For conversion, I used light Karo syrup, NaOH (pre-dissolved), and water. Butcher, in a post on this same thread, gave the amounts. For the NaOH and syrup, I always used an additional 10% above those figures. I prefer the syrup because it's already a liquid and I know how much it takes. I found it as cheap as $11/gallon (Costco) and a gallon will do about 260 oz of silver. NOTE: It's been awhile since I've done this. I've noticed that the newer Karo labels list both light corn syrup and high fructose corn syrup as ingredients. This might affect the quantity needed. Also, since dissolving NaOH is a pain, I used 50% liquid caustic soda (NaOH), which I've only seen in drum quantities. If you use it, it takes about 27ml per oz of silver.
http://www2.costco.com/Browse/Product.aspx?Prodid=10250849&search=karo&topnav=national&Mo=0&cm_re=1_en-_-Top_Left_Nav-_-Top_search&lang=en-US&Nr=P_CatalogName:BD_823&N=5000046&whse=BD_823&Dx=mode%20matchallpartial&Ntk=Text_Search&Dr=P_CatalogName:BD_823&Ne=4000000&D=karo&Ntt=karo&No=0&Nty=1&Ntx=mode%20matchallpartial 

I found this interesting mixer setup on eBay that, based on the tank size given, could be used to convert about 350-400 oz of silver per batch. I'm not sure how well the bottom drain arrangement would work without some modification - it might be best to settle, siphon off the solution, and then flush out the silver through a bottom drain into a bucket. With this particular mixer, you would need an air compressor. I'm not saying you should buy this. I'm just saying that a setup similar to this is ideal for completely converting large quantities.
http://www.ebay.com/itm/Lightnin-EV-Series-Mixer-EV1P75A-W-Snyder-Polyethylene-Cone-Bottom-Mixing-Tank-/190733984215?pt=LH_DefaultDomain_0&hash=item2c68a1a1d7

There are a lot of Lightnin' mixers on eBay.
http://www.ebay.com/sch/?_nkw=lightnin%20mixers&clk_rvr_id=409504351789

When converting, I always like to know how much total silver I'm dealing with in the batch. This will give you a good idea of how much nitric it will take to dissolve it, how much salt or HCl to drop it, and how much syrup and NaOH to convert it. There are 3 basic ways to do this.
(1) Keep track of how much silver you added as inquart and know how much was in the alloy to start with.
(2) If you are careful (don't add too much) when adding the salt or HCl, especially near the end, you can calculate the silver by knowing exactly how much it took. 
(3) The most accurate way is to analyze the nitric solution for silver, determine the total volume of solution, and then calculate the total silver. I always used the Volhard titration method, which can be set up for about $150. There is a slight learning curve but it's not too bad. I can help you with it.


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## butcher (Nov 11, 2012)

Using wire to cement silver, sometimes I use fine wire from transformers, with shellac burn off, the fine wire replaces the silver, and breaks up easier than a larger diameter wire, which seems to get coated in silver making it harder for the silver nitrate to penetrate and harder to break up crystals of silver off of the copper leaving some copper with silver powders, I only start with the fine wire, and before all of the silver nitrate is cemented, after breaking cemented silver to powders I will then hang my buss bar into solution, to finish cementing silver.

When dissolving silver in nitric acid, it is easy to have too much nitric left that can dissolve more silver, as it seems the reaction slows as acid is consumed with silver, heating can help to dissolve quite a bit more silver into solution but takes time, it is surprising how much more silver will dissolve after you think the reaction is complete.

Cleaning up copper from your last batch of cemented silver, using this new batch of silver nitrate with excess nitric.

Hydrogen peroxide can help dilute the solution and oxidize HNO2 back to HNO3 in solution to help keep free nitric in solution reacting, instead of fuming off as NOx gas, but if this is used when cementing silver on copper, the free nitric would consume more copper with the nitric, but fumes would be less.

It also seems to me that dilution of the solution when cementing can play a big part in how the reaction proceeds.

I have a chemical stirring barrel like GSP linked to, one of these can be made easy from a plastic barrel, an electric motor stainless steel rod and an stainless propeller, a plastic drain bib faucet.
Some ideas if making your own stir barrel:
The motor could be speed controlled, the impeller could be fixed to hold other metal bars, or change stir bars, like copper (for cementing silver from silver nitrate solution), or Iron for converting silver chloride in dilute sulfuric acid, and so on, the barrel could also be setup on a rocker tilt frame, so barrel can be tilted, and dumped of its contents.


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## chawimac (Nov 11, 2012)

nickvc said:


> I tried to post earlier but lost it when my iPad locked and I had to re start it. My opinion is the same as Butchers I would avoid creating silver chloride if you can. I think that perhaps you are using too much nitric and or that your not diluting it if you are getting loads of fumes when you cement the silver back out. I assume your using heat with your dissolution of the silver and base metals but if you aren't that may be part of the problem the same may be true if your using strong undiluted nitric, there are formulas for working out how much nitric you need. As with all acid dissolutions the temptation is to over use them, with hydrochloric that's not too much of a problem but with nitric it is, nitric is also relatively expensive so using only what you need makes commercial sense. I can understand your need to refine the gold quickly especially in the volumes your doing but allow the acids to do their work and only add more if all the reaction stops and then only in small increments, if your really in a hurry calculate how much nitric is needed and use less,cool,decant carefully and restart the reaction again with fresh diluted acid but again don't use too much.
> When you then cement your silver using copper the fumes should be minimal and your copper usage should reduce, if as you say you are using so much then perhaps cementing the copper back out using steel, decant filter and wash and use that powder to start the cementation but finish using clean copper.
> As your processing karat scrap you need to remember that the silver you use to inquart with also acts as a carrier for the PGMs which will be recovered amongst your silver and which will need to be put through a silver cell at some point to recover them in the slimes, any gold in your silver will also be recovered. If your not using a cell I hope your testing all your solutions with stannous and keeping a stockpot for any values your finding.
> I agree with Butcher you need to read Hoke and understand what she teaches you could be making much more money by understanding her teachings and also making your own work easier.



I follow the various recipes I have found here as far as the amounts of acid to use. I find that if I cut back on the acids I get unfinished results. I use heat and I have magnetic stirrers as well (check my other posts), and I add my acid in two batches always. Obviously I am doing something wrong or partially anyways. When you use a liter beaker, of course the fumes are not noticeable but when you use a 55 gallon barrel things change (not excusing myself here, I know my setup is flawed).

Again with recycling the copper, it is not as easy as it sounds especially 35 kilos a week.

I do test all the fluids I dispose of both with chemicals and with a meter.

Thnx for the tips!


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## chawimac (Nov 12, 2012)

Hi All,

I processed another lot today with all the great advice I received. I think I was successful for the most part, and have lots of pictures so everyone can follow along.

I started the process with about 3.5 Gallons of Silver Nitrate, which comes from digesting some carat scrap that I inquarted. As you can see I did everything in a 5 Gallon paint bucket (clean of course.) I am not sure how much silver was supposed to be there but was expecting 1200 grams more or less. I have many buckets so am not quite sure as per the amount. Will read on the recommended methods to determine contents in these solutions.

I took 5 lbs. of table salt and dissolved in water. I proceeded to add salt to the solution and mix with a drill and a paint stirrer. As you can see from the pictures, the stirrer got damaged due to the Nitric acid. Also, you will notice the fumes, again as a result of the excess Nitric. Any ideas on how to neutralize the Nitric? (Other than not overdoing it in the first place.)

I dumped the solution in my filter and diluted it with water to wash out the AgCl.


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## chawimac (Nov 12, 2012)

Once the solution was filtered, I recovered the AgCl and checked the weight. I recovered 2,524 Grams moist weight. AgCl was not allowed to dry.

I added some more salt to the original solution to check if there was any AgCl left over. There was no reaction. I assume it is safe to discard this solution... Thoughts?


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## chawimac (Nov 12, 2012)

For step two of the process I took a total of 3,000 grams of lye, which initially I thought I would need 1200 grams. I dissolved the Lye with warm water. It violently boils.

I slowly added the lye solution to the AgCl. After adding 1500 grams to the solution I filtered the solution. As you can see in the picture, I gathered the reaction was incomplete as the color was not right and there were lots of little white dots here and there. From the youtube (yes I like youtube) videos I gathered the color needed to be darker. I proceeded to double the amount of lye to a total of 3,000 grams. I was happy with the results. As expected the solution became very hot.

The mud goes from a yogurt like white substance to a creamy gray, then finally sandy dark grey substance.

One of the mistakes I had previously made was to filter and wash the lye away from this solution. I added syrup to the mix of silver oxide/lye. The syrup was simply cane sugar dissolved in water. I added 4 16oz glasses in total. The first glass I added caused the solution to violently boil, almost causing the liquid to boil over. Fortunately the majority of the liquids were removed from the bucket on the first step of this process and averted disaster. I added the next 3 glasses of syrup with caution.

The solution was filtered and washed with warm water until the water being drained was clear. Again I assume this leftover liquid is safe to be discarded.


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## chawimac (Nov 12, 2012)

In the end 1,919 grams of the silver metal sponge were extracted. This was melted and I managed to recover 877 grams of silver. Melting was smooth, exactly how it was supposed to work! I am happy. I took the silver and did an XRF assay and got .99+ results.

Comments please. Are my yields in the acceptable range? Thoughts?


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## Geo (Nov 12, 2012)

in the picture of your leftover solution. after making sure theres no more silver, you have two decent options as far i can tell.
1. evaporate just below the boiling point of water until you reduce the volume to about a quarter of what it was. add a hundred ml's of concentrated sulfuric VERY slowly and distill the nitric acid out of the spent solution. 
2. add some steel to the spent solution to collect any heavy metals. let it sit a couple of days and the solution will go from green to almost clear. check the PH and adjust to neutral. discard solution saving all the precipitation to process or discard safely.


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## butcher (Nov 12, 2012)

nice
I like the photo's, I cannot say much as my jaw is dropped.


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## nickvc (Nov 12, 2012)

I try not to blow my own trumpet but the gold shown in the picture was less than an average days refining when I ran my own refinery and I used to create silver chloride in copious amounts, dustbins full of the stuff but if I had my time over I would go the cementation route and use silver cells to recover the gold and PGMs that inevitably follows the silver. Your fumes are caused by having way too much unused nitric in your solution, even now I create volumes of silver nitrate and I dont have serious fume problems unless I have used too much nitric. The use of stirrers in your inquartation process isnt necessary and will cause your gold to reduce into powders that can easily pass with the solution and be trapped in your silver, if you follow Harold's tips you end up with solid pieces of honeycombed gold which makes losses less likely. If your processing only your own inventory the losses aren't a problem as at some point they will be recoverable as will any PGMs that are carried by the silver but if your working on customers materials you could end up with problems. The other point to remember is that by creating silver chloride your left with large quantities of solutions that will in all likelyhood have PGMs still dissolved in them but if you cement the silver the PGMs will also be cemented out leaving you with a solution barren of values.
Out of interest I would be tempted to have a full assay done on your silver and find out how much of that 1% is values and what exactly they are, by using the processes you do some gold will definitely report into your silver and if most of your silver has been cemented then they will almost certainly contain PGMs.
I'm not trying to be clever but trying to point you in the direction to make your business successful and to be able to recover all the values that are within the materials your processing, while I was refining for a living I must have lost fortunes by not understanding all the ways to recover those small values that over time mount to seriously large amounts of money....read Hoke and make it your bible to work to and your business will become even better, in this business when dealing with volumes of material it's easy to ignore those important but very small things that can make all the difference to the profitability of your business and even keep you going when others fail.


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## goldenchild (Nov 12, 2012)

Two pennies from me. Don’t worry about the nitric that evolves from adding the salt. It can't put the AgCl back into solution. You will of course have to use more steel (or whichever metal you use) to drop out your copper before discarding the solution. I see you are using a mixer in the pictures. They look a bit rusty and this can obviously contaminate your silver. I’ve never used a mixer but could there be a way of preventing the oxidation?


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## chawimac (Nov 12, 2012)

nickvc said:


> I try not to blow my own trumpet but the gold shown in the picture was less than an average days refining when I ran my own refinery and I used to create silver chloride in copious amounts, dustbins full of the stuff but if I had my time over I would go the cementation route and use silver cells to recover the gold and PGMs that inevitably follows the silver. Your fumes are caused by having way too much unused nitric in your solution, even now I create volumes of silver nitrate and I dont have serious fume problems unless I have used too much nitric. The use of stirrers in your inquartation process isnt necessary and will cause your gold to reduce into powders that can easily pass with the solution and be trapped in your silver, if you follow Harold's tips you end up with solid pieces of honeycombed gold which makes losses less likely. If your processing only your own inventory the losses aren't a problem as at some point they will be recoverable as will any PGMs that are carried by the silver but if your working on customers materials you could end up with problems. The other point to remember is that by creating silver chloride your left with large quantities of solutions that will in all likelyhood have PGMs still dissolved in them but if you cement the silver the PGMs will also be cemented out leaving you with a solution barren of values.
> Out of interest I would be tempted to have a full assay done on your silver and find out how much of that 1% is values and what exactly they are, by using the processes you do some gold will definitely report into your silver and if most of your silver has been cemented then they will almost certainly contain PGMs.
> I'm not trying to be clever but trying to point you in the direction to make your business successful and to be able to recover all the values that are within the materials your processing, while I was refining for a living I must have lost fortunes by not understanding all the ways to recover those small values that over time mount to seriously large amounts of money....read Hoke and make it your bible to work to and your business will become even better, in this business when dealing with volumes of material it's easy to ignore those important but very small things that can make all the difference to the profitability of your business and even keep you going when others fail.



Thnx for the great advice! The 1% left on the silver is copper. A lot of it is from a dirty crucible, and some from the wash process. 

I will try to dial in on my Nitric use, as its is very obvious now I am way over doing it. I cut back in the past on the nitric when removing base metals of the inquarted lot, only to have significant amounts of black sand left over after using AR. I would end up with about 10% of my material as black/gray sand which would be a mix of silver and gold (15%Au).

As for the waste waters I have from adding salt, how should I process this? Should I add copper to drop any PGMs? Or should I add Iron to recover the copper? If I add Iron, will PGMs drop out?

Thanks for the help.


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## chawimac (Nov 12, 2012)

goldenchild said:


> Two pennies from me. Don’t worry about the nitric that evolves from adding the salt. It can't put the AgCl back into solution. You will of course have to use more steel (or whichever metal you use) to drop out your copper before discarding the solution. I see you are using a mixer in the pictures. They look a bit rusty and this can obviously contaminate your silver. I’ve never used a mixer but could there be a way of preventing the oxidation?




Haha, the oxidation is because of the Nitric. Ironic. I threw out the mixer last night after one day of use as the blades became completely digested!!!


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## Palladium (Nov 12, 2012)

nickvc said:


> I try not to blow my own trumpet but the gold shown in the picture was less than an average days refining when I ran my own refinery and I used to create silver chloride in copious amounts, dustbins full of the stuff but if I had my time over I would go the cementation route and use silver cells to recover the gold and PGMs that inevitably follows the silver. Your fumes are caused by having way too much unused nitric in your solution, even now I create volumes of silver nitrate and I dont have serious fume problems unless I have used too much nitric. The use of stirrers in your inquartation process isnt necessary and will cause your gold to reduce into powders that can easily pass with the solution and be trapped in your silver, if you follow Harold's tips you end up with solid pieces of honeycombed gold which makes losses less likely. If your processing only your own inventory the losses aren't a problem as at some point they will be recoverable as will any PGMs that are carried by the silver but if your working on customers materials you could end up with problems. The other point to remember is that by creating silver chloride your left with large quantities of solutions that will in all likelyhood have PGMs still dissolved in them but if you cement the silver the PGMs will also be cemented out leaving you with a solution barren of values.
> Out of interest I would be tempted to have a full assay done on your silver and find out how much of that 1% is values and what exactly they are, by using the processes you do some gold will definitely report into your silver and if most of your silver has been cemented then they will almost certainly contain PGMs.
> I'm not trying to be clever but trying to point you in the direction to make your business successful and to be able to recover all the values that are within the materials your processing, while I was refining for a living I must have lost fortunes by not understanding all the ways to recover those small values that over time mount to seriously large amounts of money....read Hoke and make it your bible to work to and your business will become even better, in this business when dealing with volumes of material it's easy to ignore those important but very small things that can make all the difference to the profitability of your business and even keep you going when others fail.



Very well said!


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## goldenchild (Nov 12, 2012)

chawimac said:


> As for the waste waters I have from adding salt, how should I process this? Should I add copper to drop any PGMs? Or should I add Iron to recover the copper? If I add Iron, will PGMs drop out?



Process your waste solutions as normal. You'll definitely want to drop the copper out of solution. That should ALWAYS be done. As far as the PGMs go you should be testing your wastes with stannous. If it's negative but you still suspect there may be trace amounts of PMs in solution you could go ahead and try to plate it out with copper anyway. If you were to add iron to your wastes PGMs will indeed drop out with anything else under iron in the electromotive series. Simply use copper first, collect your PMs and then use iron or whichever other metal you choose to drop out the copper.


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## Richard NL (Dec 9, 2013)

Keep up the good work Richard"butcher".
Just One Little Thing.


butcher said:


> Personally I would rather use copper to cement silver from the silver chloride,


I think you meant to say: silver nitrate solution.
Silver chloride is already a precipitation from a solution.

Please correct me if I'm wrong or made a mistake,i am still learning. 

Best regards Richard.


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## butcher (Dec 9, 2013)

Richard NL,
Yes I did make a mistake in what I said, I edited the post, I have bad habit of having one thing on my mind and typing another, getting the words mixed up. I did mean to say a nitrate solution.

As we know you cannot cement silver from silver chloride.
But we do cement silver from silver nitrate solution.

Thank for finding and pointing out the mistake.


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## nickvc (Dec 10, 2013)

F you take what the real experts say about silver from inquartation it will always have other values included, gold almost certainly plus any PGMs included in the starting material. If your using an xrf to test the silver you may not get an accurate reading on the other values as they will be very low. If your producing 10 kilos of silver per week and it contains 1/4% which I don't believe is overly estimated you are throwing out $230-440 a week away in other values, take an average of say $300 that's $15000 a year. Set up a cell and refine your silver and do a recovery from the slimes once a year it will be a nice bonus 8)


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## MysticColby (Dec 11, 2013)

couple thoughts:
- you rush things. add nitric to your scrap silver slower. Instead of in 2 steps, try 10. I know it'll go slower, but you'll use less nitric and not get fumes when you add copper (because you won't have as much excess nitric after the silver is gone). If all of the silver is not dissolved, that's fine - just add it to your next batch.
- Same goes for sodium hydroxide: add it slower. boiling may be exciting, but it also has the potential to splash on you. sodium hydroxide can be worse than some acids.
- you keep saying you're adding syrup, then say sugar. everyone else is talking about corn syrup, which is not the same as sugar for this. From what I've read on the conversion using syrup method is that corn syrup works better than sucrose.


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## goldsilverpro (Dec 11, 2013)

When using the lye/syrup method, I always want to know how much silver I have in solution before adding the HCl or salt solution. If you know this, you can easily calculate the chemicals it will take all the way down the line, from start to finish. The best, cheapest, simplest, and fastest way to know the silver content of a silver nitrate solution is a Volhard titration. You could probably set up for this for about $200, maybe less, and learn it in a day. If you're doing a lot of silver, that's pocket change. When you really know what you have, everything goes smooth.

That's just one example. Analysis is where this forum has really fallen on it's face. I've tried somewhat to push it but no one seems interested. At least 50% of my monetary success in the field is attributed to my abilities of knowing what I have, at all times, through analysis. Analysis is the secret of making money in this business. Ask any legitimate real refiner.


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