# My New Silver Refinery - Thum Cell



## rybak97

Here’s my new Thum Cell….. Basically it’s a 1.5 Gallon Rubbermaid container from Wal-Mart ($5.00), and smaller Rubbermaid container from my cabinet (Anode basket, free) and one of my dog’s old water bowls (Cathode, cut and smashed to fit the container, free).


I’m using pure cemented silver shot for the anode. I've got a small ingot with a SS screw melted into it for the electrical connection (well out of the electrolyte so no SS is involved with the reaction) and a power supply from EBay (recommended on another thread). 

My solution is 6 Toz of Ag and 36 grams of Cu in 1 Gal of distilled water. The container on the left is just to use up some volume so I didn’t have to make an entire 1.5 Gal’s of electrolyte.

There is so much surface area in the anode because of the shot I’m getting great amperage through the cell and am currently running at 3.8V which results in current flow of 3.1 amps. The cell has been running for an hour and I've all ready got some good silver depositing on the Cathode, aka dog bowl!!

Please take a look and give me all the constructive criticism you can. My father always told me you don’t even know how to eat until someone tells you how to so take all the advice you can get!!


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## rybak97

Bumped it up to 4.0V after an hour and are now running 4.3 amps. Photo of crystals after two hours attached...


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## FrugalRefiner

Brian,

Based on the pictures, I believe you've created more of a Moebius cell than a Thum cell. The Thum cell is characterized by a horizontal cathode at the bottom of the cell. A Moebius cell has a vertical cathode, usually with vertical anodes. They both have their advantages and disadvantages, but they both produce silver crystals. It's more just a technical/semantic difference. Yours is sort of a combination.

In your second post you mention raising the voltage to 4.0V. You would be better served keeping it closer to 3 volts. As you increase the voltage, you're more at risk of co-depositing other metals along with the silver you're trying to purify.

Dave


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## rybak97

FrugalRefiner said:


> Brian,
> 
> Based on the pictures, I believe you've created more of a Moebius cell than a Thum cell. The Thum cell is characterized by a horizontal cathode at the bottom of the cell. A Moebius cell has a vertical cathode, usually with vertical anodes. They both have their advantages and disadvantages, but they both produce silver crystals. It's more just a technical/semantic difference. Yours is sort of a combination.
> 
> In your second post you mention raising the voltage to 4.0V. You would be better served keeping it closer to 3 volts. As you increase the voltage, you're more at risk of co-depositing other metals along with the silver you're trying to purify.
> 
> Dave



Hi Dave, 

Thanks for the input. 

The cathode is L shaped but the solution was cloudy so you really couldn’t see the bottom. I’ve attached a picture of the cathode out of solution so you can see it. I wrapped the upper part of the cathode with electrical tape per another member’s recommendation as he said I’d get better purity with crystals forming only on the bottom due to a higher Cu concentration towards the top of the electrolyte. Have you heard of this??

I dropped the voltage to 3V's and am now running at 3.3 amps. I did some more reading and read about depositing other metals at higher voltage like you said and we certainly don’t want that!! Plus, when I pulled out the cathode to take a picture there was a 3in tall silver crystal forming directly below the basket!! From what I read a lower voltage will result in smaller, denser and less "leggy" crystals. That will let me run for longer before I need to clean out. The basket is only 3.5in away from the SS cathode on the bottom.

Thanks again, keep it coming.


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## mikeinkaty

Mine is like a Moebius cell. I now have a 500 sq cm SS cathode that is 6" x 13" that makes a semi-circle inside of the glass container. When I hang 2 anodes (5 ozt each) in the cell I get 3 amps at 1.0 volt. At 2.5 volts it runs close to 10 amps. But, I generally set it at 1.5 volts producing 4 to 5 amps. At the higher amperages (> 6 amps) I get the feather crystals on the edges of the SS which is not good. That is one advantage of using a SS bowl - you get no edge effects as there are no edges! My cell generally takes about 14 hours to digest 10 ozt of anodes when running at 5 amps. Also, with the increase in cathode area I get no buildup under the anodes. Letting it run 20 ozt before cleanout produces bigger crystals. The idea of running shot in a Thum cell is a very good idea as it increases the anode area, and likewise, the amperage. My anode to cathode distance is about 3". 

Bryan - keep up the good work! The experimentation is half the fun! Mike


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## rybak97

mikeinkaty said:


> Bryan - keep up the good work! The experimentation is half the fun! Mike



Thanks Mike. I should be getting more amps out of this cell I think. I think the problem is the sive of my cathode. That shot in my anode has such a huge amount of surface area I think there might be more anode surface area than cathode surface area. The cathode Im using is probably only 16in^2. Theres no way for me to calulate the surface area of all the shot, but id bet money its more than 16in^2. Not sure how to fix that problem without increasing the volume of the cell??


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## FrugalRefiner

Brian,

You're right, I couldn't see that your cathode continued down to the bottom of your cell.

I haven't read anything about higher copper concentrations towards the top of the electrolyte, so I can't answer that question.

But you did bring up an interesting point. Why is your electrolyte so cloudy? If all you dissolved was silver and copper in HNO3, it should be a clear blue, not cloudy. Take a look at some of the other cells on the forum. Whatever is causing the cloudiness could become trapped in your crystals as a contaminant.

Watch out for those long crystals. If your power supply isn't sufficiently protected, the crystal could grow to contact the anode, shorting the circuit and possibly damaging your power supply. With clear electrolyte, you can see when this is happening and knock them down before they can do any harm.

Dave


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## goldsilverpro

There are better masking materials to use with chemicals than electrical tape.

http://www.3m.com/product/information/Electroplating-Tape.html
http://www.amazon.com/s?ie=UTF8&field-keywords=electroplating%20tape&index=blended&link_code=qs&sourceid=Mozilla-search&tag=mozilla-20

http://www.darentwax.com/products/engineering/stopping-off-wax

http://www.tolber.com/products.htm

http://www.amazon.com/b?ie=UTF8&node=700782011


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## rybak97

mikeinkaty said:


> At the higher amperages (> 6 amps) I get the feather crystals on the edges of the SS which is not good. That is one advantage of using a SS bowl - you get no edge effects as there are no edges!



Mike, Im getting some of these "feathers" at the edges of my cathode just like you mentioned above. Why is this a bad thing???


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## rybak97

goldsilverpro said:


> http://www.3m.com/product/information/Electroplating-Tape.html
> http://www.amazon.com/s?ie=UTF8&field-keywords=electroplating%20tape&index=blended&link_code=qs&sourceid=Mozilla-search&tag=mozilla-20



Awesome, never even would have known it existed if it weren't for this forum!! The electrical tape Im using is vinyl as well, but Im sure this tape has something that makes it less reactive, stronger, longer lasting, or something......


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## rybak97

FrugalRefiner said:


> But you did bring up an interesting point. Why is your electrolyte so cloudy? If all you dissolved was silver and copper in HNO3, it should be a clear blue, not cloudy. Take a look at some of the other cells on the forum. Whatever is causing the cloudiness could become trapped in your crystals as a contaminant.



I didn’t even realize that it was so important to use pure "ingredients" for the electrolyte. For it I used some of the silver shot I made from the cementation, but I also tossed in some of the fine powder I found at the bottom of the cementation vessel that I couldn’t filter. Perhaps it wasn’t silver? What do you think?


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## lazersteve

I have a case of the acid proof circuit board etching mask tape. Each roll is 3/4" wide. I use it to mask off my stainless cathode contact leads. It's really great stuff.

Steve


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## mikeinkaty

rybak97 said:


> mikeinkaty said:
> 
> 
> 
> At the higher amperages (> 6 amps) I get the feather crystals on the edges of the SS which is not good. That is one advantage of using a SS bowl - you get no edge effects as there are no edges!
> 
> 
> 
> 
> Mike, Im getting some of these "feathers" at the edges of my cathode just like you mentioned above. Why is this a bad thing???
Click to expand...


They make like (what I call) silver wool. Hard to work with. The big nodules are much better. Easier to scoop, easier to wash, etc. If they start growing they will spread across the floor and start piling up under the anode. (in my case the floor is glass) I covered the edges of my cathode with plastic report binders. They cover the edge about 1/4". I thought about black tape but didn't know if the glue might contaminate the solution. From what I read here I gather not. I may try that as I'm out of sterling and my cell is shut down. ps - I liked the beauty of the wild growing feathery crystals at first as did my granddaughters. The would stare at them a long time trying to see them grow. By the way, one publication I read said that 30 ma per square cm for a SS cathode is about the most current recommended. They also said that most Moebius cells were run at 1.5V-2.5V. Then as much current as possible without exceeding the 30ma/sqcc rule. I think they said Thum cells are generally run with 3.5-5.5V. The objective here is speed and likeable crystals. Mike

http://books.google.com/books?id=E_...AEwAA#v=onepage&q=moebius silver cell&f=false See around page 240.


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## FrugalRefiner

Brian,

It's impossible to know what your fine powder might have been. The most common metal alloyed with silver is copper, but there is no guarantee that some other metal(s) may not be in the mix. 

As with most things in life, the acronym GIGO (Garbage In, Garbage Out) applies in refining. Consider that most of us are striving for the purest metals we can get. I know that's not true in every case, as there are many for whom recovery provides them a satisfactory result. But if you're running cemented silver through an electrolytic cell, you're likely shooting for at least 999 fine silver. That only allows you a 1 part out of 1,000 tolerance. So if your final silver crystals contain more than 1 milligram (.001 gram) of contaminant per gram of crystal it's not 999. If the particles are big enough to make your electrolyte cloudy, it's likely some of them are going to settle out onto your crystals, and as the crystals grow around them they will become trapped in the crystal structure. Mother Nature does it all the time!

The cell is capable of producing 999.9 silver if you're careful. When you make your electrolyte, if it's cloudy you should filter it till it's perfectly clear before using it.

Dave


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## mikeinkaty

rybak97 said:


> FrugalRefiner said:
> 
> 
> 
> But you did bring up an interesting point. Why is your electrolyte so cloudy? If all you dissolved was silver and copper in HNO3, it should be a clear blue, not cloudy. Take a look at some of the other cells on the forum. Whatever is causing the cloudiness could become trapped in your crystals as a contaminant.
> 
> 
> 
> 
> I didn’t even realize that it was so important to use pure "ingredients" for the electrolyte. For it I used some of the silver shot I made from the cementation, but I also tossed in some of the fine powder I found at the bottom of the cementation vessel that I couldn’t filter. Perhaps it wasn’t silver? What do you think?
Click to expand...

I always filter my AgNo3 solutions whether being used for electrolyte or going into a dropping tank. I clean off the tarnish too on the sterling before dissolving using Bonami and hot water. ps - I'm on my 3rd cell design now. Will probably have more! Mike


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## rybak97

FrugalRefiner said:


> Brian,
> 
> It's impossible to know what your fine powder might have been. The most common metal alloyed with silver is copper, but there is no guarantee that some other metal(s) may not be in the mix.
> 
> As with most things in life, the acronym GIGO (Garbage In, Garbage Out) applies in refining. Consider that most of us are striving for the purest metals we can get. I know that's not true in every case, as there are many for whom recovery provides them a satisfactory result. But if you're running cemented silver through an electrolytic cell, you're likely shooting for at least 999 fine silver. That only allows you a 1 part out of 1,000 tolerance. So if your final silver crystals contain more than 1 milligram (.001 gram) of contaminant per gram of crystal it's not 999. If the particles are big enough to make your electrolyte cloudy, it's likely some of them are going to settle out onto your crystals, and as the crystals grow around them they will become trapped in the crystal structure. Mother Nature does it all the time!
> 
> The cell is capable of producing 999.9 silver if you're careful. When you make your electrolyte, if it's cloudy you should filter it till it's perfectly clear before using it.
> 
> Dave



That does not sound good!! 

I filtered the electrolyte through two layers of muslin, but not enough to remove the cloudiness. I tried to filter through a coffee filter but it got clogged almost immediately. The cell is clearing up now so I have to assume you’re exactly right; the sediment is settling to the bottom and becoming trapped in the crystalline structure. D*&M!

Well, I’m going to keep it running to completion and make my final ingots as planned. I have a local assayer that is going to check them for me on Monday so I should know if I hit .999 pretty soon. If not, I’m going make some new electrolyte with just pure silver and copper and try again. Can’t sell it unless it’s .999!!

Thanks for the input everyone.


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## FrugalRefiner

Let us know how it turns out. We can all learn through your experience. 

Keep studying. There is so much to learn.

Dave


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## Palladium

Did you use tap water to make the solution? If you did then the cloudiness could be silver chloride.


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## rybak97

Palladium said:


> Did you use tap water to make the solution? If you did then the cloudiness could be silver chloride.



No, I used distilled water for everything.


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## rybak97

OK. I did an early "clean out" of the cell and sure enough there was a VERY fine grey powder that had settled out of the solution and was at the bottom of the cell. The good news is that once I removed all the silver and placed it on Muslin all of the grey powder washed right off (at least what wasn’t trapped by the crystals). This left me with my first container of beautiful silver crystals (see photo).

I removed the electrolyte and filtered it once through 4 coffee filters, then through 5 and finally through 6 coffee filters and the solution came out much clearer than it was originally. I let that sit for 30 mins and nothing settled to the bottom of the beaker so I’m pretty sure it won’t in the cell either.

Just got her fired back up and she’s running like a champ. 

I’ll keep the updates coming and post the assay results on Monday. Thanks for all the help everyone.


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## Dawg

I'm interested on how your melt goes I had a similar issue several months ago with a batch I did, I ended up having to buy all new melting dish's had a nasty mess I did get everything fully processed had to do it twice though


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## rybak97

Palladium said:


> Did you use tap water to make the solution? If you did then the cloudiness could be silver chloride.



Also, I was using Dudadiesel Nitric 67.2%. The distilled water came from Wal-Mart. Maybe the Nitric was low quality? Does Wal-Mart sell bad distilled water? I don’t know which variable to change first. 

If it is silver chloride, will that affect the purity of the silver?


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## rybak97

Dawg said:


> I'm interested on how your melt goes I had a similar issue several months ago with a batch I did, I ended up having to buy all new melting dish's had a nasty mess I did get everything fully processed had to do it twice though



What about the items in this thread makes you worried about the melt??? Why did you have to buy new melting dishes and what was a nasty mess?


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## metatp

Brian,

I think it is important that the silver you use to make your electrolyte is as pure as possible. I would use the crystal you make with this run to make your next electrolyte. Even when I use the crystals, I still filter it encase something fell in there. BTW, I don't use copper in the electrolyte, and it seems to work best for me. The cemented stuff I use for anodes have a little copper (about 1%) already in it.

Tom


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## Palladium

I've learned that the cloudiness only shows up for me from chlorides. Not saying that could or couldn't be your problem. Chlorides can not only be introduced from the water. anything you have used or touched that has any chlorides in it will carry over if you touch the silver nitrate solution with it. Filtering apparatuses, beakers, stir rods, anything that might have residue! It doesn't take much to make chlorides that cloud your solution. Good news is though that if it's just a little bit and you keep running then it will clear itself up. Shouldn't hurt anything. I can't give you the science but it's never affected my purity to the amount that i can tell it. Now that grey and black you speak of is a different story. The screw you have in the top of that don't look stainless to me. How do you know it's (real) stainless?


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## rybak97

Palladium said:


> How do you know it's (real) stainless?



It was advertised as stainless steel deck screws, and it throws sparks when I hit it with a grinder. However, I just hit it with a rare earth magnet and it is slightly magnetic. It must be ferritic stainless. Is that a bad thing?

It looks weird because I heated it to red hot before using it to burn off any coatings or oils that might have been there.


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## Palladium

rybak97 said:


> Palladium said:
> 
> 
> 
> Did you use tap water to make the solution? If you did then the cloudiness could be silver chloride.
> 
> 
> 
> 
> Also, I was using Dudadiesel Nitric 67.2%. The distilled water came from Wal-Mart. Maybe the Nitric was low quality? Does Wal-Mart sell bad distilled water? I don’t know which variable to change first.
> 
> If it is silver chloride, will that affect the purity of the silver?
Click to expand...


I buy my nitric from the same chemical supplier as Duda does and i use wal-mart water to so i don't see that as a problem.


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## rybak97

Palladium said:


> rybak97 said:
> 
> 
> 
> 
> 
> Palladium said:
> 
> 
> 
> Did you use tap water to make the solution? If you did then the cloudiness could be silver chloride.
> 
> 
> 
> 
> Also, I was using Dudadiesel Nitric 67.2%. The distilled water came from Wal-Mart. Maybe the Nitric was low quality? Does Wal-Mart sell bad distilled water? I don’t know which variable to change first.
> 
> If it is silver chloride, will that affect the purity of the silver?
> 
> Click to expand...
> 
> 
> I buy my nitric from the same chemical supplier as Duda does and i use wal-mart water to so i don't see that as a problem.
Click to expand...


Maybe it was a dirty bucket? Next time ill use all new and cleaned equipment to remove that variable.


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## metatp

rybak97 said:


> Palladium said:
> 
> 
> 
> How do you know it's (real) stainless?
> 
> 
> 
> 
> It was advertised as stainless steel deck screws, and it throws sparks when I hit it with a grinder. However, I just hit it with a rare earth magnet and it is slightly magnetic. It must be ferritic stainless. Is that a bad thing?
> 
> It looks weird because I heated it to red hot before using it to burn off any coatings or oils that might have been there.
Click to expand...

I would definitely stay away from that screw. If something isn't marked, I first check it with a magnet, and then I would try it in some nitric. 

I only had cloudiness once early on in my cell experience. I used that batch for my future batches of electrolyte, and it worked out great.

Tom


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## mikeinkaty

Palladium said:


> I've learned that the cloudiness only shows up for me from chlorides. Not saying that could or couldn't be your problem. Chlorides can not only be introduced from the water. anything you have used or touched that has any chlorides in it will carry over if you touch the silver nitrate solution with it. Filtering apparatuses, beakers, stir rods, anything that might have residue! It doesn't take much to make chlorides that cloud your solution. Good news is though that if it's just a little bit and you keep running then it will clear itself up. Shouldn't hurt anything. I can't give you the science but it's never affected my purity to the amount that i can tell it. Now that grey and black you speak of is a different story. The screw you have in the top of that don't look stainless to me. How do you know it's (real) stainless?



I learned that the hard way just a few days ago. I had filtered some silver chloride with my buchner funnel and forgot to wash it out when done. Couple of days later I used the funnel to rinse some crystals and the water was coming out milky. WTH!! The silver chloride had dried and caked inside the funnel. I had to wash the heck out to get it all out of there! I also accidentally picked up some Spring Water at a store the other day instead of distilled water. I caught that immediately when rinsing something (forget what). But the rinse water was running a funny cloudy color from it too. I did get 2.3 ozt silver from the silver chloride that I found caked up in the bottom of a 5 gallon bucket. That silver looked to be pretty pure.


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## g_axelsson

Palladium said:


> Chlorides can not only be introduced from the water. anything you have used or touched that has any chlorides in it will carry over if you touch the silver nitrate solution with it. Filtering apparatuses, beakers, stir rods, anything that might have residue! It doesn't take much to make chlorides that cloud your solution.


That is really true. I have a beaker with some silver in and when I get some excess nitric I pour it into that beaker, it kills the acid and I get silver nitrate from it. When I have enough I run that batch to finish and cement the silver with copper.
Anyhow, one day I put a beaker with HCl next to it. A couple of days later I discovered that the silver nitrate were covered with a pale purple surface, the HCl had evaporated from one beaker and reacted with the silver nitrate on the surface of the other beaker... and this was even standing outside on a table. :shock: 

The lesson, keep your HCl away from your silver, it can spread even through air.

Göran


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## rybak97

Going backwards through the steps I used I’ve come to the conclusion that the water I used in the hot water bath caused the introduction of Cl. I was using a SS vessel over flame to heat a water bath where my beaker and watch glass were partially submerged.

The water I used in the SS vessel was from the tap. I think the evaporating tap water combined with the condensate on the watch glass and dripped into my reaction vessel. Since I was doing this outside, in the sun, it caused the chloride to turn purple and made my solution very cloudy.

Since this first run I've started using dark reaction vessels and no heat, I’m just patient and let the Nitric do its thing all night. This last batch was crystal clear and as blue as the Keys.


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## mikeinkaty

rybak97 said:


> Since this first run I've started using dark reaction vessels and no heat, I’m just patient and let the Nitric do its thing all night. This last batch was crystal clear and as blue as the Keys.


Someone here told me to not heat a AgNO3 solution so I quit doing it and must say that I have not seen a real need for it when digesting silver with HNO3. No explaination was given as to why not. Like you I do my reactions outside and usually start them early enough in the day so that I have time to add the 2nd batch of acid before turning in at night. By the next morning it's usually done. I throw in a spare piece of sterling at that time to see if the acid has quit reacting. After about 1 hour if no visible signs of a reaction exists I prepare for the copper drop. I use quart canning jars and find it convenient to do 10 ozt sterling at a time.

Mike


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## Dawg

Rybak: I had a redish Brown Slag that would not melt I was using a MAPP torch


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## Alentia

rybak97 said:


> I didn’t even realize that it was so important to use pure "ingredients" for the electrolyte. For it I used some of the silver shot I made from the cementation, but I also tossed in some of the fine powder I found at the bottom of the cementation vessel that I couldn’t filter. Perhaps it wasn’t silver? What do you think?



Cementation at best produces 98% silver with 2% of any crap possible.

That exactly where your problem with cloudiness lies. Electrolyte should be prepared with 999 silver and copper. I normally use sterling silver previously boiled and washed with NaOH.

They call it: garbage in - garbage out.


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## Glen Billeter

Hello to all. 

Brian, excellent job of showing how it's working for you. This is my first day
on this site and I am amazed with all the good information you guy's are providing for rockies like myself. [Hoping to be a pro one day]. 

I have been trying to figure out the best way to find the value of silver in a
yard of sand and gravel. A friend of mine gave me his copy of Hoke's book.
I have been reading and trying to understand and remember the different 
processes for silver and gold. 

After concentrating I took the final material and extracted as much free gold
as I could. After that I ran all rock and gravel through a rock grinder down to nano size 100 mess and up to -12 mess . Then I took the concentrate and put in large glass jar. I add 70% Nitric and covered material by approximately 1". I did use regular tap water and diluted solution. My friend said that was ok. I started to get the red smoke and a lot of bubbles and increased temp. I let this sit over night. 

The next day I proceeded to filter liqued through coffee filters. This is a
very slow process, having to change filters 6 or 7 times. In my filters I thought I would have a lot more sludge, which I was told held all the silver. This material doesn't have any silver if I understand correctly now. 
In the container I have a nice blue liqued. I added copper tubing to the solution and watched it start bubbling. This totally consumed the copper tubing I had added.Now I have poured that liqued through coffee filters. I saved all the filters with the sludge. I am going to burn of all paper 
and sludge and hope that I have some silver. 

The question is: what do I do from here. Does the blue liqued hold any silver . Is making a Thum cell the best way to fixthis problem and extract the silver. We drilled 57 holes and took over 600 samples. Assay came back with 50 to 200 oz of silver per ton. 
I don't know if I believe those results, so I'm going to do my own tests. 

Thank you if any one can help. 

Glen Billeter
Gold Rush Alaska
Fine Gold Recovery Specialist 

[email protected]


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## Palladium

Welcome to the forum Glen. I'm not much of one for extraction from ores so i can't help you there. I can tell you that if your silver is in the nitric acid in solution and you added copper and it eat it up while producing red smoke that you have to much active nitric acid for the silver to drop. It will drop and then redissolve back into the solution the whole time eating up copper until all the free nitric is used up. Then the silver will start to drop. Did you roast the material?


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## Palladium

Oh cool ! I just realized who you are sir. Welcome on board !


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## solar_plasma

I am a bit unsure, if I should post this now, since you guys are pro's (and palladium is one of the silver refining gods), but if I have understood the problem right, some of your questions are fairly easy to answer: After dissolving in nitric acid your silver should not be in the filter sludge, but dissolved in the filtrate. Have you tried to precipitate a sample of the clear blue filtrate with HCl to form unsoluable white AgCl? This will also precipitate from acidic solution.

Until the pro's answer, here's a first hint: The cells in this thread are used for refining, not for recovering. To recover from AgNO3 containing solution the silver mostly will be precipitated or cemented, then (if pure enough) melted and used as a cathode in a cell in order to refine it.


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## butcher

solar_plasma, is correct,
You can test a small sample of the copper nitrate (after you cemented silver with copper) using HCl or table salt NaCl, if you have silver in the blue solution, you will see a milky white reaction if enough silver is left in solution you will see a white curds of precipitate of silver chloride.

Grinding, gravity, or some other means of concentration of the ore, and roasting of the concentrates is important for any leaching of ore, but I know even if I had an ore rich with silver, nitric acid would cost me more than I could make from any silver recovered, with the price of fuel today I do not know I would do any better smelting the ore.

If silver is dissolved into the nitric acid leach another method beside copper to cement it out of solution could be electrolysis (or the silver chloride method with salt above), with electrolysis you would need a graphite inert anode, and stainless steel cathode to recover the silver, this method would also push out other metals in the solution out of the electrolyte along with the silver onto the cathode, if they were involved in the ore (such as copper...)

Also you may want to do small assays on samples before and after an extraction or leaching process, example depending on what type of material or ore you are working with you may find that after you gravity separating your gold (black river sand for example) you may find most of the silver was actually in the gold you removed by gravity, and very little was left in the remaining iron ore.


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## Alentia

Glen Billeter said:


> The next day I proceeded to filter liqued through coffee filters. This is a
> very slow process, having to change filters 6 or 7 times. In my filters I thought I would have a lot more sludge, which I was told held all the silver. This material doesn't have any silver if I understand correctly now.
> In the container I have a nice blue liqued. I added copper tubing to the solution and watched it start bubbling. This totally consumed the copper tubing I had added.Now I have poured that liqued through coffee filters. I saved all the filters with the sludge. I am going to burn of all paper
> and sludge and hope that I have some silver.



Glen,

1. You are correct on first one, the sludge after Nitric processing most likely does not have any silver. (Unless you had not enough Nitric, as per below you had excess). In some cases if you have cobalt or any other metals more reactive than silver they may digest all Nitric and drop silver as cement, in this case that mud will have lots of silver. Please see below about H2SO4 use.
2. If your copper pipe dissolved in the solution, you have to feed more until it does not dissolve and there should be almost no bubbling (what you have is too much nitric in your solution)
3. Cemented silver should not look like sludge, but like a cement. You still have silver in the solution, do not proceed to "table salt" until your solution digest enough copper it is saturated with it and can not "eat" more of it.

I have recently processed prospectors silver ore. I would recommend to treat it with Sulfiric Acid before or in the middle of the process. Sulfiric acid will digest all the "other crap" if you use at the beginning. It will convert any nitrates developed back into nitric if you use it in the middle of the process. Wash well before and after changing acids.

Do not breath "brown fumes", even releasing them into atmosphere in Alaska is not so good idea. NOx is deadly.


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## Platdigger

Alentia,

I understand your post except for this line: 

"do not proceed to "table salt" until your solution digest enough copper it is saturated with it and can not "eat" more of it."

Why keep adding copper when a small test could be made with salt or hcl to confirm if indeed there is any silver in solution?


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## solar_plasma

> "do not proceed to "table salt" until your solution digest enough copper it is saturated with it and can not "eat" more of it."



Once I have precipitated silver from hot 4M HNO3/H2O2 1:1 with 2M HCl - no prob

I prefere HCl, because no unnecessary new ions are added and it's very precise, since it reacts that fast, so the last drop will not force further precipitate, only a chlorine-yellow tint occurs around the drop. Most in here know that, but I am just glad, when it happens, that I can take the chance to give a correct answer :lol: ....hey, there was something, I know about 8)


----------



## Alentia

Platdigger said:


> Alentia,
> 
> I understand your post except for this line:
> 
> "do not proceed to "table salt" until your solution digest enough copper it is saturated with it and can not "eat" more of it."
> 
> Why keep adding copper when a small test could be made with salt or hcl to confirm if indeed there is any silver in solution?



If the idea to measure exactly how much silver is per weight, introducing AgCl into the solution will not help. 

If the idea to see if there is any silver in the solution, NaCl can be used.

If all of the copper pipe was digested, it does mean either:

1. Nitric was in excess, but silver is present (no need for NaCl, keep digesting copper until silver starts to cement on the pipe)
2. No Nitric soluble metals are in the solution (NaCl test may help here)


----------



## solar_plasma

Alentia


> If the idea to measure exactly how much silver is per weight, introducing AgCl into the solution will not help.



:shock:

Okay, so you mean AgCl-method is not quantitative or too complicated? But when you want to measure quantitative, cementing on copper won't be either, if you don't know if there are other dissolved metals than Ag with a lower electronegativity than Cu AND cementing will never give pure Ag. It's therfore we refine cementet stuff further. I don't know anything about ores, maybe this fact is negligible? If so, cementing may be easier.

Though I would prefere AgCl: neutralize if you want, drop, filter, wash with hot water, dry, weigh, and just to be sure: dissolve again, filter, dry, weigh, weight 1 minus weight 2
multiplicate with factor 0,7526251526251526

quantitative: yes (AgCl 1,88 mg/l)
complexity: a 14 year old child can do that (well I could, when I was 14)

...would be done within 1 hour

Dropping AgCl is the way to go, especially, if you want to_ measure exactly_.

Please correct me, if I am wrong. Don't get me wrong, nonetheless I appreciate your skills! I know you are a thousand times more erxperienced than I am.


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## g_axelsson

I'm with Solar here. There is no need of extra copper in the solution unless you want to cement the silver on the copper.

Another way to do it is to use HCl to drop the silver as a precipitate and reuse the leach. If done correctly you could add just enough HCL to turn most of the silver into AgCl. The nitrate would turn back to nitric acid again and can be reused as a leach. The important thing here is that you should add just enough to precipitate MOST of the silver but not all. As long as you have a bit silver nitrate left there can be no free chlorides in solution. If you add too much HCL and use it for leaching the ore then it will turn the silver into silver chloride in the ore and you wouldn't get it out. But don't dispair if you have added too much HCL, just add a bit of silver nitrate dissolved in water until there is no more precipitate. Now all the free chlorine is gone.

Eventually the other metals leached from the ore will exhaust the acid and you will need to make more.

The silver chloride can be turned back into metal again via the sodium hydroxide / syrup method or other methods. It's all here on the forum.

But to economically extract silver with nitric acid from ore you have to have an extremely rich ore, highly concentrated ore or extremely cheap nitric. The NOx gases are also a problem, could be counteracted by adding hydrogen peroxide.

Welcome to the forum, Glen! 8) 

Göran


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## Alentia

It might be a matter of personal preference.

I do not like dealing with AgCl due to the following reasons:

1. Too bulky by volume vs cemented silver
2. Requires extra steps
3. Almost impossible to get rid of Copper Nitrate with washes
4. Takes too long to settle after each wash

I am usually dealing with around 3-5kg of silver per batch, all of the above will introduce extra days for me. Washing Silver Cement with H2SO4 as I have described in another thread solves cement impurities issues.


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## FrugalRefiner

solar_plasma said:


> Though I would prefere AgCl: neutralize if you want, drop, filter, wash with hot water, dry, weigh, and just to be sure: dissolve again, filter, dry, weigh, weight 1 minus weight 2
> multiplicate with factor 0,7526251526251526


I wouldn't advise members to dry their AgCl. When it dries it forms a crystaline structure that makes the conversion process more difficult and can result in loss of values. It can still be accomplished, but the crystal structure needs to be broken down to ensure complete conversion to metalic silver. It is better to keep your AgCl wet until it is converted.

After it has been converted to metallic silver, it can be dried and weighed (or melted and weighed) for a quantitative result.

Dave


----------



## solar_plasma

frugalrefiner


> I wouldn't advise members to dry their AgCl. When it dries it forms a crystaline structure that makes the conversion process more difficult and can result in loss of values



Yes, convert it to AgOH and calcitate it, would be a way. But I thought the main goal was a quantitative test on silver, therefor drying and weighing without too many steps between. The loss you will have und calcination and melting, so from this point its not quantiative anymore.


----------



## solar_plasma

Alentia


> 1. Too bulky by volume vs cemented silver
> 2. Requires extra steps
> 3. Almost impossible to get rid of Copper Nitrate with washes
> 4. Takes too long to settle after each wash
> 
> I am usually dealing with around 3-5kg of silver per batch, all of the above will introduce extra days for me. Washing Silver Cement with H2SO4 as I have described in another thread solves cement impurities issues.



I was talking about a sample for testing, gramms not tons. For recovering ofcourse you take the easiest way, when ppm not matter.
With a vacuum pump this is done in minutes with samples up to 100g. It would be a nightmare to do this with 5kg silver, I guess.

Hey you guys are professional, I would expect, that you have better and more specialized lab inventory than I at school.


> Washing Silver Cement with H2SO4 as I have described in another thread solves cement impurities issues.



For revovery and refining ingenious, but not quantitative analysis.


----------



## FrugalRefiner

solar_plasma said:


> Yes, convert it to AgOH and calcitate it, would be a way. But I thought the main goal was a quantitative test on silver, therefor drying and weighing without too many steps between. The loss you will have und calcination and melting, so from this point its not quantiative anymore.


I guess it's a matter of your point of view. From a theoretical point of view, any loss suffered during melting would affect the quantitative result. But from a real world point of view, you're going to melt it eventually, so any loss in melting reflects the true amount of silver you may be able to recover.

If I have a sample of material and I just create AgCl, dry, and weigh, I know what _might_ be recoverable. But if I follow the process through to completion I know what _can_ be recovered. There _might_ be contamination in the AgCl. There _might_ be some loss of values during conversion to metallic silver. There _might_ be loss during the final washing and melting. So I _might_ be dissappointed that what I calculated based on the weight of the AgCl is higher than the button I end up with after melting.

You are right that from a scientific perspective minimizing the steps involved in the analysis eliminates possible losses along the way. But what matters to me is the weight of the button or ingot I can hold in my hand after I've completed the process. It's just a different point of view.

Dave


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## Glen Billeter

Thank you to all: 

I certainly see that I have a lot more studing to do or hire someone who knows what they are doing. lol

I was confused a little. I have 2 bottle of silver nitrate. I added more copper pipe to solution and it coninued to bubble. So I am assuming that the Nitric
was still present in the solution. I've let that sit for an extra day. Now I see
lots of white foamy stuff on top and some brownish sludge on the bottom.
This is out of 2 -5 gal buckets of ore. Test on this material have shown that there is between 50 - 200 ozs of Ag per ton of material. I don't need absolute results, just some stong indicators that , yes indeed, there is silver present. We also have about 10-15 grams of gold per ton. We have
approximately 70,000,000 yards of this material. 

What I'm really not sure of is the best way to drop out the silver. I diluted 
with a little distilled water. I wasn't sure if I added a little salt to solution
to drop silver or is there something else I need to do also. I was going to filter out silver and then burn off. 

Thanks to anyone who can help. 

Glen Billeter


----------



## skippy

Glen Billeter said:


> Thank you to all:
> Test on this material have shown that there is between 50 - 200 ozs of Ag per ton of material. I don't need absolute results, just some stong indicators that , yes indeed, there is silver present. We also have about 10-15 grams of gold per ton. We have
> approximately 70,000,000 yards of this material.


 
Is that 70 million cubic yards? If the tests are representative of the whole 70 million yards, then you have many billions of dollars of metals and, yes, you should probably consider hiring serious professionals to help you. I am not a professional, but maybe you need a flunkie? :lol:


----------



## Alentia

Glen Billeter said:


> Thank you to all:
> 
> I certainly see that I have a lot more studing to do or hire someone who knows what they are doing. lol
> 
> I was confused a little. I have 2 bottle of silver nitrate. I added more copper pipe to solution and it coninued to bubble. So I am assuming that the Nitric
> was still present in the solution. I've let that sit for an extra day. Now I see
> lots of white foamy stuff on top and some brownish sludge on the bottom.
> This is out of 2 -5 gal buckets of ore. Test on this material have shown that there is between 50 - 200 ozs of Ag per ton of material. I don't need absolute results, just some stong indicators that , yes indeed, there is silver present. We also have about 10-15 grams of gold per ton. We have
> approximately 70,000,000 yards of this material.
> 
> What I'm really not sure of is the best way to drop out the silver. I diluted
> with a little distilled water. I wasn't sure if I added a little salt to solution
> to drop silver or is there something else I need to do also. I was going to filter out silver and then burn off.
> 
> Thanks to anyone who can help.
> 
> Glen Billeter



Use salt only as indicator that there is still silver in the solution. As you would be normally proceeding by using copper cementation, do not even look at NaCl(salt) as your option for those quantities of ore.

Do not waste distilled water, you do not need it at this stage for silver.

The brown stuff you see at the bottom is your silver cement. Keep dissolving copper until reaction stops. Most likely you have other organic and inorganic matter in the bucket.

I would recommend following:

1. Let this batch run its course
2. Start new batch
3. Use about 1gl of ore, 1gl or water and 1/2gl of Sulfiric Acid - let it sit for 24 hours stirring once every 2-3 hours
4. Discard solution by decanting (let is settle on the angle - you can put it into another open bucket at 45 degrees)
5. Wash with regular water 3-4 times, settle and decant. no need to filter
6 Add another gallon of water to the ore
7. Add nitric to exactly as per estimated silver content. If you think you have 500gr of silver in 1gl of ore, add exactly 500ml of Nitric
8. Let it work its way through for about 24 hours, stirring occasionally
9. Let it settle and decant
10. Repeat step 5
11. Drop copper pipe into the decanted solution, you should have about 5gl of the solution based on all decanting sufficiently diluted with water
12. Add 1/2 of water to the remaining ore and about 200ml of H2SO4, let it settle for 24 hours
13. Repeat step 5 into new backet. Test with salt, it no silver present discard.
14. You may repeat step 7 with 1/5 of nitric used first time to see if there is still any silver left keep this one for at least 48 hours for full reaction.

When I mean discard it is worth while to treat solution with NaOH to pH 10 before discarding otherwise you may introduce some acid diluted metals, which should not get into close by rivers. Dissolved metals are poison to wild life and humans.


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## Platdigger

Sounds like a good ore to try thiosulfate on myself.
Sodium thiosulfate will take up silver without any additional chemicals.


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## Alentia

Platdigger said:


> Sounds like a good ore to try thiosulfate on myself.
> Sodium thiosulfate will take up silver without any additional chemicals.



Platdigger,

Can you please expand and explain?


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## ilikesilver

Glen Billeter said:


> Thank you to all:
> 
> I certainly see that I have a lot more studing to do or hire someone who knows what they are doing. lol
> 
> I was confused a little. I have 2 bottle of silver nitrate. I added more copper pipe to solution and it coninued to bubble. So I am assuming that the Nitric
> was still present in the solution. I've let that sit for an extra day. Now I see
> lots of white foamy stuff on top and some brownish sludge on the bottom.
> This is out of 2 -5 gal buckets of ore. Test on this material have shown that there is between 50 - 200 ozs of Ag per ton of material. I don't need absolute results, just some stong indicators that , yes indeed, there is silver present. We also have about 10-15 grams of gold per ton. We have
> approximately 70,000,000 yards of this material.
> 
> What I'm really not sure of is the best way to drop out the silver. I diluted
> with a little distilled water. I wasn't sure if I added a little salt to solution
> to drop silver or is there something else I need to do also. I was going to filter out silver and then burn off.
> 
> Thanks to anyone who can help.
> 
> Glen Billeter




Just wanted to say, what a honor to have you on board!! thanks for joining, cant wait for the new season to start up, love the show. tim


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## Glen Billeter

Thanks everybody. 
This has been quite an experience for me. I haven't had 
to deal much with chemicals. In 1984 when I first started mining for gold,
I was in the jungles of Colombia, SA . As a rockie mining and in my excitement finding so much gold I wasn't very safe or smart. We used mercury for all our recovery and clean up. I didn't know it at the time, but after 6-7 years had gone buy, I become very sick and half crazy. A Doc. in Seattle who specialized in mercury, discovered that I had serviour mercury poisioning. It's taken almost 20 years but I finally am free of mercury. Now I feel a 100 times better, but my wife thinks I'm still a crazy gold miner. LOL. I use all safety gear now. 

I want to learn as much as I can in a short time. I very much appreciate your
time, expertise, advice and friendship. I DO NOT plan on doing this full time for the mine. We will hire someone or sell the concentrates. The value is "through the roof". All I need is the simplist way to test ore in the field and come up with a value. 
I'm starting to see some other operations , on Gold Rush and other places, that it looks like they are throwing away thousands of $ in gold and silver. 
I want to show this and be able to prove quickly. 

After using nitric and adding copper until all the bobbling was gone, I have been filtering off. Very slow process. It looked like a lot of sludge on the bottom, but it didn't show up in my filters. (That I could see anyway). I will burn that when I have a good curcible in a couple of days.
I was wondering after pouring off the liquid If I could add salt with HCL and zinc to see if there is any silver left. I don't know if this is a good idea. 
Will I get the same reaction now that I have added copper or will that make a difference. Leaving the copper in doesn't seam to make a difference now. 

I have some stainless pans and I was thinking about making one of those 
Thum Cells to use on all the liquid left. 

I think you are correct about the contaminats in the material. I will remove 
the garbage on the next test with sulfuric acid. Then add the nitric and then the copper. Is there a good way to clean up all the liquid I have so I can drop the silver or is it a lost cause. 
Also, should I heat the new material before starting and if so how hot should I get it. Should I repeat the heating in between steps after rinsing material. 

Sorry about being long winded. I'm having way to much fun.!!!! 8) 
Thanks for your response.


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## 4metals

If all you want to do is get paid fairly for the value of the ore then why aren't you simply fire assaying the ore? Good sampling and sample prep and you know what you have. Anyone who is considering buying the ore to process will certainly be having it fire assayed first. (If he's not, send him to me, I have a bridge to sell him!) 

If your buyer will be evaluating by fire assay, wouldn't you want the same benefit on your side of the transaction?


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## Alentia

> Also, should I heat the new material before starting and if so how hot should I get it. Should I repeat the heating in between steps after rinsing material.



Heating ore will help to get rid of any organic matter, so you do not waste your acids. Otherwise, H2SO4 will take care of it. Drying and heating ore between acids will help, but not much, I would not waste any time.



> Is there a good way to clean up all the liquid I have so I can drop the silver or is it a lost cause



If you referring to "current" batch you are processing and you had mention no effect on copper anymore. Whatever sediment you have at the bottom should be silver.


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## Glen Billeter

Well I followed the process with fresh ore. Add Sulfuric and let work for
24 hrs. It was still showing bubbles and signs of working so I let it go another day. Cleaned and washed cons 6-7 times. Add water and then Nitric. 
Nitric was working, lots of bubbles, but no red fumes. Let it sit and work for 24 hrs. Poured off in to bucket. Let settle and decanted washed 3-4 times. Had about 4 gals of solutions. Added new copper pipe. Pipe cleaned a little, but other than that,..... nothing. No bubbles. No fizzing. No activity at
all. Can anyone tell me what I've done wrong. I have 5 more buckets with
nitric working but I don't know if I should do the same thing. Any Ideas. 

Thanks 
Glen Billeter


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## solar_plasma

You want to know, how much silver there is in the ore, right? If so, then take one litre of the solution, add small amounts of HCl, stir, wait till the surface clears a bit, add a bit HCl again...do this until no more white silver chloride forms when adding HCl. Instead of HCl you can use NaCl, like Butcher already said.I just like to do it with HCl since I believe the reaction is faster and more precise, but it doesn't matter, what you take. You can even add an excess of chloride. Then let it sit some hours or a night and decant. Wash, dry, weigh and multiply the weight in gramm with 0,7526251526251526 and you know how much silver there is in one litre of your solution.

That IS the proper way of quantitive analysis of silver, - ask any chemist. It IS. This way you will find every single milligram of silver. Only 1,88 mg/l will stay dissolved in water. In acidic condition it may differ a bit, but also that could be calculated. I remember those lessons from highschool/college, I just hated it, when I was a pupil/student. If there is only a little silver compared to your gallons of solution, cementing will take maybe weeks, the silver will be unpure and you will not recover every milligram unless you brush your copper, then you will probably not only have cemented all non silver precious metals but also have some copper in it.

Cementing is for revovery. Precipitating Ag+ as its chloride is quantitive analysis.


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## butcher

Glen Billeter,
As you know the compounds of ore can be very complicated as to the chemical makeup of the ore and the metals involved, many of these ore's were formed from acids although there are some formed from an alkaline, since sulfide are probably the most common lets focus on them for a minute, if we tried to use this directly in acids we could have problems, not to mention some of the possible danger from the fumes (hydrogen sulfide gas or arsenic...), after concentration we need to take the finely crush the ore, and roast it to red hot in an oxygen rich environment, with good stirring this will improve our ore, convert metal sulfides to metal oxides, helping our later leaches to react with the metals in the ore.

The roasting can also help to remove chemicals in the ore that can act negatively with our leaching process.

The sulfuric acid would be good to get copper, and would not dissolve the gold, but if you are trying to leach silver I do not think I would use sulfuric acid, as it can make silver sulfates which are not very soluble, then if going to a nitric acid leach after wards you may have trouble converting the silver sulfate to a silver nitrate solution, without roasting the material again before using your nitric acid.


----------



## Glen Billeter

Thanks Butcher,

I think sometimes I get in to much of a hurry to get done.
After washing out the sulfuric, I didn't take the time to heat the material. 
I will test a small amount tomorrow with hcl. If that works, can I add that 
to my larger quantities of silver nitrates that I have. Just to make sure I
understand, by adding the hcl to the silver nitrate, the silver will drop out
and I can wash it and then melt to a button. Is this correct? I have some 
liquid that is very dark,[almost black], dark blue to and very lite blue-green color. Will it work the same for all solution strength. Will there just be a
larger or smaller amout of silver. 

Thank you

Glen Billeter


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## solar_plasma

No, the silver will drop as AgCl, white unsoluable powder. This has to be reduced first before melting. There are several ways, but as Alentia said, it's more work than cementing from silver nitrate. So, it's optimal for analysis. Cementing may be better for large quantities.

I would treat AgCl with NaOH to AgOH and NaCl, wash well and dissolve it in HNO3 to AgNO3, which I would add to the AgNO3 stock for cementing. *Edit: But this I only would choose, because it is easiest to me. There are better methods.*


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## butcher

Silver chloride will precipitate form a dirty solution of nitric acid and other metals, the silver chloride (most chlorides are soluble, silver being one of the exceptions), the silver chloride may drag down some other metals from the solution as if forms the curds, you may have to give the silver chloride a little more time to settle.

The silver chloride cannot be melted back to metal, as much of the silver chloride would be volatile, and just go up in the white smoke, the silver chloride needs to be converted back to metal before melting, there are several methods of converting the silver chloride, NaOH & Karo syrup, dilute sulfuric acid and iron, or aluminum and HCl, you can learn about these methods on the forum.

With a flux heavy in sodium carbonate it is possible to convert the silver chloride in the a melt, as you heat and then melt the silver, but I suggest you convert it to silver before melting.

Silver cemented from solution by using elemental copper metal, can be washed well, and then dried and directly melted, because the silver is cemented out of solution as elemental silver metal powder.


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## solar_plasma

One method from internet, I used my first time, I absolutely *NOT *advise: silverchloride, water, acid and pieces of zink in a bucket. I had that much AgCl left in my partly cementet silver, that when I tried to melt it, nearly 50% was blown off as smoke.


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## Alentia

Glen Billeter said:


> Well I followed the process with fresh ore. Add Sulfuric and let work for
> 24 hrs. It was still showing bubbles and signs of working so I let it go another day. Cleaned and washed cons 6-7 times. Add water and then Nitric.
> Nitric was working, lots of bubbles, but no red fumes. Let it sit and work for 24 hrs. Poured off in to bucket. Let settle and decanted washed 3-4 times. Had about 4 gals of solutions. Added new copper pipe. Pipe cleaned a little, but other than that,..... nothing. No bubbles. No fizzing. No activity at
> all. Can anyone tell me what I've done wrong. I have 5 more buckets with
> nitric working but I don't know if I should do the same thing. Any Ideas.
> 
> Thanks
> Glen Billeter



Glen,

If nothing had cemented on copper, that would mean, no silver in the solution. Unless, there was not enough nitric and silver got cemented by other metals, right in the digestion bucket.

I had observed with ore, due to mutliple metals present (as butcher mentioned), brown gas is not always generated to digest silver, as it probably getting absorbed by something else in the ore.


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## solar_plasma

We talk about 1,5-6 g silver per kg ore dissolved in some gallons of acid. That ist not much for cementing, but much for chloride precipitation. As an example I remember my silver solder with 1% silver, rest Cu and Zn. I only dissolved some 100 mg in 20ml HNO3 and I got a visible chloride reaction with some drops HCl. I leave it to the reader's math to calculate how many mg of silver that was.

It could be that all the silver was bound as sulfides as butcher pointed to and I really don't know, if those would react fast enough with diluted acids, so it could very well be, like altentia said, that there is no silver in the solution, but still in the ore. If there is any, would one drop of HCl show.


----------



## Glen Billeter

Well, I took 1 liter of solution from 2 different samples. Both had almost 
no action with the copper. I added hcl to each one , got nothing, I added more and got nothing. I added a total of 20 ml to each 1 liter test. no action at all. It looks like there is zero amount of silver in the solution. I believe you are correct that maybe the solution of nitric added was to diluted in material and the silver got cemented to other metals. I had the solution from my very first test so I decided to do the same test. I poured all the different bottles of solutions from my first test, into 1 large glass jar, about 4 liters. I started adding hcl and stiring. With in 1 min, a gray cloud of material started to drop to the bottom. I added more hcl and keep stiring. With in 5 mins I had 2 inches on the bottom and much more dropping. After about 1 hr I now have about 4 inches of heavy gray on the bottom. I'm going to assume that this is my silver. I will let it sit over night. 
Question: Do I pour this through a filter or slowly pour off top liquid, leaving sludge on the bottom, let it dry and weight. 

Thanks to everyone for your comments and directions. 

Glen Billeter


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## solar_plasma

Let it clear, decant the top liquid off, fill up with destilled water, stir, let it clear - at least 3 times. Then again decant off the clear liquid and wash the powder down in a filter - coffee filter will do it. Then dry and weigh. If there is lead in the ore the washings should be done with hot water.

I guess this procedure works with some kg or maybe some hundred, but :lol: I am sure, that way you don't want to extract the silver from your whole mountain of ore - you need to hire an expert to find and set up the best process for it. I don't know anything about ores, but I guess it will be some kind of leaching to do it big style.

... or you send one ton ore to each one of us and you get half of the silver back :lol: *just joking*


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## g_axelsson

If you want to process your silver chloride with NaOH and caros syrup then you should NOT let your silver chloride dry up.

The method of converting silver chloride into metallic silver with NaOH and caros syrup is discussed in many places on the forum. I guess there is also a link to the topic in the forum guided tour.

Göran


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## skippy

Nitric acid dissolves lead, but adding sulfuric acid will precipitate it as lead (ii) sulfate and adding hydrochloric will precipitate it as lead (ii) chloride. So if you dissolved your ore with nitric and then added HCl you would get lead (ii) chloride as well as silver. Silver sulfate is slightly soluble, so carefully adding small doses of sulfuric acid with *lots* of stirring may allow you to precipitate lead first. The volume of chlorides precipitated makes me think you have a lot of lead in there.


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## Alentia

Glen,

Do not dry (seems)grey/white powder. Lead chloride and sulfate should be easily soluble in hot/boiling water, while silver chloride will not.

Since you get to the chloride, you have to wash it (preferably in hot water) until solution is clear (no blue color), do not filter, decant only.

When wash is done, add water about the same amount of chloride and drop piece of iron in it, add H2SO4 about 1/10 of water and let it sit there for a day stirring occasionally. White precipitate should be converted into grey cement/big flakes/crumbs. If white small flakes still left around add about 1/10 of H2SO4 and stir. You can repeat the above until no white flakes left at the bottom or floating around. Discard solution and wash cement with hot water.

For the bucket where you get no silver in the solution, wash sediment by decanting 3-4 times, when finished washing, add a bit of water (around 100ml or to cover) and bit (25ml) HNO3, stir and observe if there is a reaction after about 10-15 min.


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## solar_plasma

Yeah sure, if your main goal is to reduce and melt it, don't dry. Dry only, if you *only *, precise and fast as possible, want to know,* how much* silver it is. But in the last step - melting and casting - you will probably have losses again. So that isn't quantitive anymore. You want to measure, how much silver there is, you don't want to measure how much silver YOU with your set and setting, your skills and this method get out of it. Makes no sense to me. I guess you want to get comparable, validated measured values. You have to know, if you are measuring exactly what you want to measure and not some correlating phenomenons, side effects, artifacts and inaccuracies.

Sorry, but I feel like being home, when we talk sampling and measuring - keep the system simple.

So, both ways are ok. It depends on what exactly you want.


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## kjt124

This method of dilute H2SO4 and iron sounds like it is a heck of a lot easier and cleaner for converting AgCl than the NaOH and Karo... If you don't really have any access to the iron laminant sheets from transformers (as has been discussed before as a good source of clean iron), would the additional carbon in pig iron pose any problems? Or perhaps would a mild steel be a viable option? Perhaps I am just looking with the wrong eyes, but I am not having much luck finding relatively pure iron.

Thanks,
Kevin


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## butcher

Kevin,
Fairly pure iron is very rare nowadays, most everything nowadays is made from steel, I have used concrete re-bar to convert silver chloride in dilute sulfuric acid, it worked well.

Glen,
I am not sure how much understanding you have of these metals and acids, but a good way to learn is with small experiments, get you some old scrap sterling silver, and do some small experiments, with this metal, these experiments, doing this can give you a better understanding of what to expect, of course the reactions will be a little different with these more pure solutions, than when these metals are in your ore, a few experiments could be done with a little bit of silver added to the ore sample , experiment run to see if you recover more than the added silver or lose silver from the chemistry of the ore.


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## kjt124

Thanks butcher. I'll play around with it a bit.

Kevin


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