# 400 LBS of newer silver plated flatware question



## drpepper843 (Sep 17, 2020)

Hello guys,

Drpepper843 here. New to the forum. Happy to be here. Have followed recycling of precious metals for a long time but have never dove in. Well, until recently. I just purchased a pallet of silver plate flatware (Mainly forks) from a local auction. They are all newer made in France and were for a formal dining hall at the Wynn casino. I was told they were silver plate but I'm not certain. Some are new in the box and show tarnish. Other people have the same flatware listed on eBay selling as silver plate. So I just assume they are. 

My main question is, If I buy a gallon of nitric acid, is it viable to assume I could possibly be able to strip all the silver and use copper to recover the dust, melt it down and make a descent amount of silver? 

The metal seems to be slightly magnetic but the magnet barely sticks. So I assume its a type of stainless under the silver plate. 

Any input will be greatly appreciated. Thanks in advance

I'd attached a few pictures but I don't know how


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## drpepper843 (Sep 17, 2020)

Maybe this Link will work. These are the same forks

https://www.ebay.com/itm/Wynn-Casin...rentrq:9c5c21251740a4e86bfd7301fffca33e|iid:1


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## Lou (Sep 17, 2020)

If it truly is Ag over stainless then yes, nitric acid will remove the silver and leave the stainless behind as passivated metal.


Having done stuff like this in the past, many tens of thousands of pounds, what I would do is set up a stripping bath in nitric, a stainless basket, then a DI rinsing bath, then another DI rinsing bath, then stack them on a perforated plate to drain.

The main bath will produce NOx and should be vented. The main bath will also get depleted and can be regenerated by adding c. HCl in small quantities to precipitate out the Ag as AgCl and regenerate more nitric acid per the following equation:

AgNO3 + HCl = AgCl + HNO3

To do that "trick" you should really learn how to do a quick Volhard titration (take a look on the forum search, very good post by 4metals).


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## FrugalRefiner (Sep 17, 2020)

drpepper843 said:


> I'd attached a few pictures but I don't know how



See Attaching Images or Files, Working with Attachments.

Dave


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## rickbb (Sep 17, 2020)

Would have to high end flatware to use stainless as the base metal. 

I use a lot of old flat ware in making scrap metal sculptures almost all I've touched is a white/pot metal base. Which is also barely magnetic.

Only way to know is to cut them open and put a drop of nitric on them and watch for any reaction.


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## Lou (Sep 17, 2020)

The first one he does he will know.


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## drpepper843 (Sep 17, 2020)

Thank you guys for the input. I was thinking about a 100 piece test to see how much I'm able to recover. I've just never done it before so I'm a little reluctant. I've watched several videos from streetips and it seems relatively straight forward. Anybody based in Las Vegas that might want to make a day of it? Ill provide the beer lol


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## jmdlcar (Jan 6, 2021)

How long will it take the Nitric Acid to remove the Silver from Silver Plated Flatware?


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## nickvc (Jan 6, 2021)

The problem with plated flatware is the base metal under the silver as the nitric will dissolve them in preference to the silver and may well cement out any silver in solution.


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## kurtak (Jan 6, 2021)

nickvc said:


> The problem with plated flatware is the base metal under the silver as the nitric will dissolve them in preference to the silver and may well cement out any silver in solution.



I agree - nitric I a VERY poor way to try to de-plate silver - once the nitric breaks though "some" of the plating the nitric is going to go to work "more" on the base metal & less on the silver - therefor you are going to use up a LOT of nitric dissolving base metal before the silver is completely de-plated & you may not even get all the silver to de-plate from nooks & crannies 

Cyanide would be a far better option

Kurt


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## nickvc (Jan 6, 2021)

With the cost of nitric and the price of silver recovering silver from plated material is normally a losing proposition, you can strip the plate using hot sulphuric with a small amount of nitric but that for me is already a big no no, the amount of silver you can recover hardly seems worth the effort in my opinion unless you are doing very large amounts.


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## Martijn (Jan 6, 2021)

I just started on my plated French silverware in the H2O stripping cel, and found out from a site that my Christofle plated ware is plated silver on an alloy. 
From the site: "The metal that Christofle uses for silverplating is called “maillechort” in French or nickel silver " an alloy of nickel, zinc and copper
https://www.google.nl/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwijqIGNvofuAhXuQEEAHfVhDLkQFjACegQIAxAC&url=https%3A%2F%2Fwww.smpub.com%2Fubb%2FForum7%2FHTML%2F000788.html&usg=AOvVaw215fx_6Sx3m452_UilNucB 

So i don't think it's stainless underneath. it's also hard to see when the silver is done deplating, and when nickel or zinc start to deplate.. will have to test my brown gray mud for those metals. 
Very careful with nickel compounds > carcinogenic. 

I have done one knife, and the knife itself seems to be stainless, no effect to the sharp end in the H2O cel @ 30 Volts. The handle is plated.

Martijn.


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## Martijn (Jan 6, 2021)

To add: this process is very very very slow and took me three evenings to strip 15 items like spoons (flattened in the vice) and forks. Will test later if most silver is off or there is still some remaining. Again, very hard to see. 
A brass base would be a lot easier.

As long as I am in the shed stripping PCB's, it's ok to run and keep an eye on, not having to wait between the turns or changes. 
400LBS is a no go for me with this process :shock: I have 10 kg of plated stuff. 

And since there is nickel the mud from this process has to be refined even further, cutting on the "profit" of your silver… 
Don't know if these levels (...tbd) of nickel and zinc cause problems in the Silver nitrate cell.

Ebay may be a faster way to make some money, or sell it to a scrap dealer, they won't even bother giving you a price for silver, may even charge you some for it.. 

Martijn.


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## jmdlcar (Jan 6, 2021)

I am going to stick with Sterling Silver. The H2O Cell you need a lot of Silver Plated stuff because what I did I got less then 2 grams and it took 2 days to do.


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## Martijn (Jan 6, 2021)

I got curious after your results so i went and recovered some mud. Here are my first results after two days of stripping: 6 grams of silver from 8 large spoons and 6 forks and two smaller other plated pieces. 
I ass.u.me its pretty pure... 95%+...

I dissolved the brown mud (+/- 30ml, while wet) in distilled water on a hotplate at 60 C and adding small amounts of nitric. 10 ml 50% in total. 
Some gray/pink dust would not dissolve. Will test later what that is. 
Next time i will rinse the mud filter with some very dilute warm nitric, the silver dust dissolves very fast. No brown fumes noticed. 

There is still some silver left in the cementing beaker and some turned into silver chloride after dumping some rinse water in a beaker with a little tapwater left in it. 
I've put that in the AgCl pot. Some more nice white cheddar formed. I think i recovered 90% of the silver from this mud into the nugget. 

I'm going to give the sripped items a second run to see if anything is left. I have a feeling there is. 

Here are some pic's: 


Little 6 gram nugget with a clumsy borax dimple from the crucible. 



The (partially?) Stripped spoons and forks. 



Some silver still cementing

Martijn.


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## FrugalRefiner (Jan 6, 2021)

Martijn, thanks for sharing your results. Do you happen to have a starting weight for the flatware you processed? Results will always vary depending on manufacturer, type of item, age, wear, etc., but any data is good data.

Dave


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## Martijn (Jan 6, 2021)

I will weigh the deplated items tomorrow. I have 10 kg to strip.


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## Lou (Jan 7, 2021)

No nitrogen oxides because what you're dissolving is already done being oxidized to Ag(I)...it's Ag2O.

You can likely mix the powder with borax and a small amount of nitre and probably be at pure Ag. Hard to tell with Ni though.


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## Martijn (Jan 7, 2021)

The deplated flatware weighs 1.341 kilo. 
The dark spoon was bent and used as a cathode after being deplated to have it pointing toward the anode hafway up the beaker. 



@lou: thanks, now I know its relatively safe to rinse the filter straight with warm dilute HNO3 to get the silver out. Saves on transfers. No need to scrub NO. But it still needs to be done in my fume hood!
Will have to get the ratio of nitric / mud right so some silver will be left undissolved and no free nitric is left when cementing. 
And not knowing what nickel and zinc do in this process i went for dissolving and cementing. Don't want any nickel in my dirty silver crucible. 
Looking at this amount and weight i think the lot weighs more than 10kg. I guesstimated that while standing on the scale and subtracting my own weight..

Martijn.


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## Martijn (Jan 7, 2021)

Some more data: 
Stamps on the fork



Weight of one spoon:


Weight of one fork:


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## Slochteren (Jan 7, 2021)

Also 6 gram from 1,3 kilo flatware? If you do it for fun/learning it's OK I think. If not better sell it as is, you get 24 euro per kilo for 90/100 stamped flatware. 

Verstuurd vanaf mijn STK-LX1 met Tapatalk


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## Martijn (Jan 7, 2021)

Yeah, I know its not much, and i won't get rich from it. Just for the sake of learning and general knowledge for others to make their decision to do it or not. 
Sometimes it's just not worth chasing tiny amounts. In this case there is no way to make a profit on it. 
But i'll have some more silver to play with. 
I am just hungry for knowledge i guess. Its kind of an addiction :roll: 
But i think there is about 1 gram still left in the cementing beaker. And there may be some still on the flatware, i am working on that now. Will take some time to finish. I am going to take it slow and stop when the material looks different on the surface. 
Have to look for a silver test to test the surface to be sure.


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## jmdlcar (Jan 7, 2021)

I know there not much on Silver Plated Stuff but @72 retired it give me something to do. I been looking and there is Silver Plated Stuff around and cheap but it add up. After I seen what Martijn got and his amount he did, what I did mind don't look that bad. The H2O Cell is safe to do I will start getting some more Silver Plated Stuff to do.

Martijn your Little 6 gram nugget looks great.


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## Martijn (Jan 7, 2021)

Thanks. 
And great to hear my results made you give it another try. 
I'll run the silver together with other e-scrap silver through my small silver cell to get nice pure crystals. 
Love that shiny stuff.


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## jmdlcar (Jan 7, 2021)

I have about 500 grams of Streling Silver to do after I receive my 70% Nitro Acid then I should get about 14.87 Troy Ounces.

I ask my Landlord today when anyone move out save all Silver and Gold stuff he fine for me.


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## Martijn (Jan 12, 2021)

Update: filtered the electrolyte in between redoing the partially deplated spoons. 
After one new spoon and three deplated spoons and one deplated fork i got another six grams. 
It took more HNO3 to dissolve this time due to more other oxides i think. The spoons come out looking horribly scarred. Still some silver in hollow parts where the current won't go. I'll consider that a loss. 

Melted it together with the last button in a new little bar. 




So i'm expecting at least another 10 to 15 grams from the rest of this now 1.4 kilo of flat ware. (1 new spoon added)

That could be close to 200 gram for the bag of 10 kg. Maybe more. So 1.5% to 2% of the weight is pure silver plating. 
Kind of acceptable for a process that only needs turning of an item every two hours or so. And the nitric wash is easy and fast without NO fumes. I am going to save the 'slimes' until its all done. 
Running the cell at 25 volts now. Resulting in +/- 200mA. 
Nitric use so far: about 25 ml 5% HNO3. So about 2ml used per gram of silver recovered. 
Cementing the silver on a copper sheet from my coppersulfate cell. 

Will post the total yield when this small bunch is done.
And some time next year, the total yield of the whole bag. :lol: 

Martijn.


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## jmdlcar (Jan 12, 2021)

I got done with all my Silver Plated Flatware when I get my Nitric Acid I will do a Nitric wash on what I did and when I Cementing the silver on a copper I will give a update on how many grams I get.


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## Shark (Jan 12, 2021)

It is possible to scale this up. Larger tote with a serving tray on one side and several pieces of flatware suspended from a copper bar works pretty good. Cut the serving tray to fit works better.

If I have to get bored, I prefer to be bored and pick up a bit of change in the process,


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## Martijn (Jan 13, 2021)

I dreamt about a slowly rotating automatic clamping and turning conveyor belt system over a long bath tub... :lol: :lol: 
Just have to get the feeding system right :lol: :lol:


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