# Is it potentially worthwhile to remove the plating from ~50kg of silver plated copper servingware?



## Cryogaijin (Dec 23, 2021)

I live near a Goodwill "outlet" store. For those only familiar with normal Goodwills, the outlets are full of bins of mixed "junk" that wasn't purchased from the normal Goodwill stores. I frequently see silver plated copper serving dishes going through the bins, and have started snagging them for their copper value. (Purchases over 25lbs are only $1.50 a lb, so about a third the spot price for copper. Good deal for me.) I haven't done much with silver thus far, but I'm curious if there is a reasonable way to extract the silver, or if I should just leave it in the copper ingots I'm making? Would the tiny amount of silver contamination in the copper impact the quality of bronze or brass made from it?


----------



## kurtak (Dec 24, 2021)

Cryogaijin said:


> I haven't done much with silver thus far, but I'm curious if there is a reasonable way to extract the silver, or if I should just leave it in the copper ingots I'm making? Would the tiny amount of silver contamination in the copper impact the quality of bronze or brass made from it?



I am a bit confused as to what you are actually asking

Based on your thread title you are asking if it is -
potentially worthwhile to remove the plating from ~50kg of silver plated copper servingware​
The answer to that would be that - yes - it is *potentially* worthwhile to *remove* the silver plating from the plated objects

But then in your post you ask - "if there is a reasonable way to *extract* the silver" (from ingots)

Those are two different things - both can be done --- the question is the potential of being worthwhile - or not 

Removing the silver (before melting) from the plated objects has the potential of being worthwhile - if you have enough to make it worthwhile setting up to do it

It's a leaching process so you would/could set up to do that (strip the silver off of the copper - leaving the copper)

You can strip (leach) the silver with ether a cyanide solution - or a sulfuric/nitric solution - or (not absolutely sure about this) an iodine/iodide solution --- you then recover the silver from the leaching solution

Extracting the silver from copper ingots can be done - it's an electrolytic process using a copper parting (refining) cell

This is normally done as a process to purify copper - not a process to recover &/or purify silver - the silver just becomes a byproduct of the copper refining so is likely not worthwhile - if your goal is to recover/purify silver because the silver is "secondary" to the copper refining process

Will the silver impact the quality of your brass/bronze ? 

Generally speaking - no - not if you are simply casting "basic" brass/bronze items (like a bell or art forms etc.)

On the other hand if you are wanting to make brass/bronze alloys for specialized industrialized applications then you need to start with "purified" elements (such as pure copper/tin/zinc etc.) in order to make the brass/bronze to the "industrial standard" of the called for brass/bronze

Kurt


----------



## Helian (Dec 25, 2021)

Can you describe the sulfuric/nitric solution stripping process in more detail? Won't the acid attack the underlying copper once it's exposed, leaving the silver?


----------



## MicheleM (Dec 25, 2021)

Helian said:


> Can you describe the sulfuric/nitric solution stripping process in more detail? Won't the acid attack the underlying copper once it's exposed, leaving the silver?


I'm Interested too, i would guess that copper is oxidized by nitric and then "passivated" by the concentrated sulphuric


----------



## galenrog (Dec 25, 2021)

If your goal is to recover and refine silver plating, you will fail financially. There is no known method of removing and refining silver plating that is in the least way profitable, once all costs are considered. If your goal is to refine recovered copper, an industrial scale copper refinery can be profitable, with silver as a bonus. 

My preferred use of silver plated copper is cementation of silver from solution. The small bit of silver from the plating is a bonus.

Time for more coffee.


----------



## speed (Dec 25, 2021)

The plating is easily stripped in a salt water electrolyte. Very little cost in consumables but the time involved adds up to way more then the value of the silver recovered unless you have semi automated process and ALOT of scrap to process.

If you melt the plated items then the silver would be recovered in a copper refining cell but again the economics arent there unless you process tons 

As a hobby go for it tho!


----------



## justinhcase (Dec 25, 2021)

I would not try and recover the silver conventionally.
But I would use it as sacrificial copper in silver recovery.
That way you do not waste any acid and still retain all metals of value.


----------



## kurtak (Dec 26, 2021)

speed said:


> The plating is easily stripped in a salt water electrolyte.



You do not need to use salt water (salt added to the water) --- you can do it with straight up tap water

here is a thread (very long) where it was discussed back in 2014

very interesting discussion









Processing SilverPlate With H2O Cell


Hi to All, Ok where to begin! I guess with the specs of my cell,so here they are. POWER SUPPLY(Front Panel) Radio Shack Regulated 12 volt Power supply Converts 120 VAC to 12 VDC 1 on/off power switch POWER SUPPLY(Back Panel) 120 VAC 60 HZ 60 WATTS MAX OUTPUT 13.8 VDC- 2.5A 3 AMP reset switch...




goldrefiningforum.com





Kurt


----------



## Helian (Dec 26, 2021)

Stripping silver plate is potentially profitable because recyclers are now paying close to $4 per pound for bare bright copper. I don't know of any paying anywhere near that for silver plate. Bare nickel silver is worth even more. In other words, stripping may be worthwhile as a means of recovering the underlying metal, with any silver recovered adding a bit to the profit. That said, and with no interest in economic pontifications, I repeat my question. What are the details of the stripping processes mentioned above?


----------



## kurtak (Dec 26, 2021)

galenrog said:


> If your goal is to recover and refine silver plating, you will fail financially. There is no known method of removing and refining silver plating that is in the least way profitable, once all costs are considered.



That's just not true - there are large scale refineries set up for cyanide leaching to strip plating from plated items

Normally speaking they run their cyanide leach systems to leach gold plating --- however they will also run silver plated through their cyanide system if you send them enough silver plated to run through there system --- they would not do so if it was not profitable 

Example; - I used to send circuit boards to a company called Enviro-Chem in Rogers Minnesota for smelting

They also bought silver plated items for which they paid a bit over number 1 copper price (whether it was plated on copper or brass - they didn't care what it was plated on)

They threw it all into a gaylord (for those that don't know - a gaylord is a 4 ft X 4 ft X 4 ft shiping container) when they had several gaylords of silver plated items they sent them to a refinery for cyanide leaching

They were certainly not paying a bit over number 1 copper & then sending it in for cyanide leaching if it wasn't profitable

Keep in mind - that if you send silver plated to the scrapyard - you have to file or grind each piece so they know if it is plated on brass or on copper - if it's plated on copper they pay number 2 copper price - if it is plated on brass the pay yellow brass price - if it's not scratched (filed or ground) they buy it all as brass even if some of it is copper 


galenrog said:


> My preferred use of silver plated copper is cementation of silver from solution. The small bit of silver from the plating is a bonus.
> 
> Time for more coffee.



That is certainly one way to recover the silver plating 

However - you sacrifice some of the copper (the copper goes into solution during the cementing process)

You then need to cement the copper back out of solution with iron

You then need to smelt the cemented copper & pour ingots as there are VERY few scrapyards that will buy copper cement

on the other hand - if you set up to leach (strip) the silver off the copper/brass you recover the silver plus end up with the copper/brass without having to recover the copper from solution & then smelt the cemented copper

My point being that if you have enough silver plated it can be worthwhile to set up for a leaching (stripping) process

Which (stripping) process is best for you is up to you

The options are ----------

1) the H2O cell (as provided in link in last post)

2) cyanide leaching

3) sulfuric/nitric leaching (works much like cyanide)

4) not sure about this one but --- iodine/iodide leaching MAY also work in which case it would be much like cyanide or sulfuric/nitric

Kurt


----------



## kurtak (Dec 26, 2021)

Helian said:


> What are the details of the stripping processes mentioned above?



I can not give you details on that process as I have never used the sulfuric/nitric process

However - Geo has & does use that process - so MAYBE he will chime in with the "details"

That said - as I understand the process - it is a process used to strip the plating without effecting the copper or brass & is therefore used in industry where the item(s) are intended to be replated 

In other words - a plating batch that ended up with plating defects so they strip the plating in order to re-run it in their plating process - or - strip items so they can re-plate them as a restoration process of items that have had the plating worn off the item

As I understand it - the plated item is submerged in a 90 - 95 % (by volume) sulfuric to 5 - 10 % (by volume) nitric & I believe it is done cold (no heat applied) 

I assume that is working with both acids concentrated (no dilution)

This (as I understand) allows the silver to go into solution - without effecting the copper/brass

As I understand - the silver is then in solution as silver sulfate so the silver can then be recovered ether as -----

1) silver sulfide by cementing the silver from the solution with iron - the silver sulfide can then be smelted along with iron using borax & soda ash as your flux --- in other words - you first reduce the sulfate (silver in solution) to sulfide with iron (a precipitated silver + sulfur) as a cementing process - you then further reduce the sulfide in a smelting process with iron (again) as the reducer causing the iron & sulfur to going off in the flux/slag there by giving you back your silver

with this option the solution becomes waste when done because the solution is "loaded" with iron after the cementing process

For what it is worth I have recovered MANY kilos of silver in this recovery process - in other words I was sent sulfate solutions &/or cemented sulfides for processing (reducing) to silver --- I have just never tried to dissolve silver as a sulfate

Or - the other option -----------

2) is to drop the silver from the sulfate solution as silver chloride using HCl & then reducing the AgCl buy your preferred method of AgCl reduction 

with this method I believe (&/or as I understand) you can recover your sulfuric for reuse - again not sure here but think/believe it is ether a simple evaporation process (the nitric &/or HCl evap off leaving the sulfuric) or an actual distilling process

Again - I have never tried to strip/leach silver plating with this process - so Geo would be the one to correct me where I may be wrong &/or provide better details

Personally - if I were to set up to strip/leach silver plating I would go with a cyanide process as I know the cyanide process & IMO (knowing the cyanide process) working with cyanide is less dangerous then working with large volumes of concentrated sulfuric --- but that is just my opinion

Kurt


----------



## kurtak (Dec 26, 2021)

Just to give you an idea on whether it is worthwhile "stripping" the plating from silver plated items here is a post (on page 8) from the thread I posted a link to earlier (H2O cell) --- the post is by solar_plasma (near the bottom of the page) dated June 4 - 2014









Processing SilverPlate With H2O Cell


I read some hours about everything I could find that could be part of the explanation. And I got some ideas in my simple mind: Cathode: nascent hydrogen Anode: nascent oxygen oxidizes the silver/anodizing silver => Ag2O (brown) (maybe also hydroxo/oxo/aqua complexes, which I hardly understand)...




goldrefiningforum.com





using the H2O cell - he put a silver plated serving tray in the cell

When the tray was "new" - it was estimated to have 180 grams of silver plating on it

the tray was old to some of the plating was worn off

however - with the H2O cell he stiped "about" 130 grams of silver from the tray - BUT - also mentions that not all the silver had yet been stripped

The tray was "about" 2 foot long & "about" 16 inches wide

Having handled many sterling silver trays that size I would guess the tray (depending on thickness) was "about" 2 to 3 pounds of copper - so "about" $8 - $12 worth scrap copper

He stripped 130 grams silver from the tray (so "about" 4 OZT silver)

At todays silver spot price ($22.86) X 4 = $91.44 - plus the copper equals "about" $100

Even if you factor it at 85 - 90 % spot you are still at $85 - $90

I would say it was worth stripping the plating

Keep in mind - the H2O cell is VERY slow (taking hours) - but - you can be doing other things while the cell runs

On the other hand - cyanide &/or sulfuric/nitric leach/stripping is MUCH faster (minutes instead of hours)

So - at least theoretically you should be able to leach/strip more plated metal then in a cell

Also - it is easier to "scale up" for leaching then for running a cell

Just saying --- there is more then one way to skin a cat

Kurt


----------



## Helian (Dec 27, 2021)

Thanks, Kurt!


----------



## kurtak (Dec 27, 2021)

Helian said:


> Thanks, Kurt!



I hope that Geo will chime in here to provide better details to the sulfuric/nitric process &/or make any corrections to what I posted as he (Geo) has actually worked with this process 

Kurt


----------



## snail (Dec 27, 2021)

Search sodium sulfite silver. It will bring up several interesting threads.
It’s my go to method, in my opinion superior to H2O cell.
I have used it in stainless pots, office waste basket, up to a narrow plastic garbage can with stainless cathodes on either side.
Creates a soft silver sludge on the cathodes that falls to the bottom of the container. It dissolves to a relatively clean nitrate solution, not much copper contamination.


----------



## Geo (Dec 28, 2021)

Thank you Kurt. I will strip some silver plate and post it on the group. I think there is a video upload now on the forum. It will make getting video up easier. It's very easy but more dangerous as it's concentrated sulfuric acid and the dangers that comes along with that. The NO2 production is minimal but still needs to be addressed with good fume control.


----------



## justinhcase (Dec 28, 2021)

Cryogaijin said:


> I live near a Goodwill "outlet" store. For those only familiar with normal Goodwills, the outlets are full of bins of mixed "junk" that wasn't purchased from the normal Goodwill stores. I frequently see silver plated copper serving dishes going through the bins, and have started snagging them for their copper value. (Purchases over 25lbs are only $1.50 a lb, so about a third the spot price for copper. Good deal for me.) I haven't done much with silver thus far, but I'm curious if there is a reasonable way to extract the silver, or if I should just leave it in the copper ingots I'm making? Would the tiny amount of silver contamination in the copper impact the quality of bronze or brass made from it?


Just wanted to make sure you are talking about silver plated serving dish.
Never seen them my self.
But what I do know is tin and copper sauce pans.
The very highest traditional sauce pan is copper because of the conductance, and they are lined with tin.
Tin was found to be completely retarded as far as human biological process, so was used in such instances.
But the untrained eye might confuse traditional cooking implements with silver plate.
On another note, copper pans do sell very well and can very easily be brought up to servable standard.


----------



## kurtak (Dec 29, 2021)

justinhcase said:


> Just wanted to make sure you are talking about silver plated serving dish.
> Never seen them my self.
> *But what I do know is tin and copper sauce pans.*



Justin

Per the bold print - when you say sauce *pans* are you talking about actual cooking pans/pots (copper)

They are (I believe) plated with chrome - not tin - tin plating does not make sense

why do I say that - two reasons - tin is soft so stirring the food in a cooking pan/pot would cause the tin to scratch & ware - also - tin is quite reactive to acids so cooking acidic foods (acid plus heat) would react with the tin causing (at least some) to dissolve & end up in the food you are cooking

Crome is hard & acid resistant

Concerning serving *dishes* (used mostly to serve meals at the holiday family dinner table)
you will fined them in three classes

Sterling silver for the rich/wealthy (class)

Silver plated - usually plated on copper or brass for the middle (class)

Crome plated (*maybe* tin plated - as they are used for *serving* food - not *cooking* food) on sheet iron for the poor (class)

Also - though not always - silver plated will normally have a hallmark of some kind & though the item may not say "silver plated" the hallmark will tell you the company that does the "silver plating" 

Here in the U.S. it is not uncommon for this stuff (the silver plated) to end up in the thrift stores so if you know what you are looking for you can actually pick up a good amount of it

You can/will find this silver plated not just as knives/forks/spoons but ALL serving dishes --- coffee/tea pots LARGE & small serving trays &/or bowls etc. etc. --- anything used for serving the meal at the holiday dinner table

If it's plated on copper or brass it is more likely then not silver plated

Kurt


----------



## snoman701 (Dec 29, 2021)

High end copper cookware is regularly plated with tin. 

It's wear is expected, and regular retinning is an expected expense.


----------



## justinhcase (Dec 29, 2021)

kurtak said:


> Justin
> 
> Per the bold print - when you say sauce *pans* are you talking about actual cooking pans/pots (copper)
> 
> ...





https://www.youtube.com/results?search_query=re+tin+copper+cook+ware


----------



## Helian (Dec 29, 2021)

Interesting, snoman. Tin is so easy to scratch and melts at such a low temperature that it's surprising anyone would put up with it in cookware. Evidently there are people who are a lot more passionate about cooking than me.


----------



## Cryogaijin (Dec 29, 2021)

justinhcase said:


> Just wanted to make sure you are talking about silver plated serving dish.
> Never seen them my self.
> But what I do know is tin and copper sauce pans.
> The very highest traditional sauce pan is copper because of the conductance, and they are lined with tin.
> ...


Yup, referring to silver plate over "pure" copper. No idea how pure the copper is, but should be over 97% given the color and sound. I have 2 large platters (3lbs even, about 18"x9" or so.) I have a dozen plates (from about 8" to 16") and a dozen goblets of various sizes, and 3 teapots/pitchers. (Tested, plated copper) 
I also have a good assortment of silverware, but that is plated over stainless, and I'm simply going to put those in my Event Hosting collection.


----------



## Cryogaijin (Dec 29, 2021)

kurtak said:


> Also - though not always - silver plated will normally have a hallmark of some kind & though the item may not say "silver plated" the hallmark will tell you the company that does the "silver plating"


Yup. Most of my nicer pieces have their Mark. (Quite a bit is Oneida, out of NYS) Several are "* Silversmith" 
I do have a couple pieces that just have "made in india" on them. I'm dubious of those, and will likely be simply melting them into ingots to eventually turn into axe heads. (Project for next year involves casting a couple dozen bronze and brass axe heads and splitting mauls)


----------



## kurtak (Dec 30, 2021)

Cryogaijin said:


> *I also have a good assortment of silverware, but that is plated over stainless,* and I'm simply going to put those in my Event Hosting collection.



Are you sure the silverware (knives/forks/spoons) are stainless steel ?

I ask because SS silverware is rarely if ever plated with silver

The base metal used for silver plated silverware is more often then not a nickel brass commonly referred to as nickel silver or German silver

It's an alloy of copper (about 60%) nickel (about 20%) & zinc (about 20%) *& contains NO silver*

The nickel acts as a bleaching agent bleaching the red color out of the copper turning the copper silver/white just as nickel bleaches the yellow out of gold to make white gold - so it's a silver/white brass

The nickel also makes the brass harder so it doesn't scratch &/or bend as easy as copper or brass does which is why they use it for making the silverware

Also silver does not plate well to SS whereas it does plate well to the nickel brass

There are 3 ways to test if it is nickel brass rather then SS

SS is MUCH harder then nickel brass so you can test it with a file - a file will scratch the nickel brass much easier then SS

Acid test - if its nickel brass a drop of 50% nitric acid & 50% distilled water will react with the nickel brass & the drop will turn blue after the reaction --- nitric acid will not react with SS

Sound test - brass has a ring to it (like a bell or tuning fork) --- SS does not --- so if you hang a spoon or fork from a string & hit it (like you would a tuning fork) it will have a "nice" ring to it whereas SS wont

Because of this ring nickel brass silverware makes very nice wind chimes

Kurt


----------



## kurtak (Dec 30, 2021)

Cryogaijin said:


> I do have a couple pieces that just have "made in india" on them. I'm dubious of those,



you can test them to see if they are silver plated or tin plated

HCl does not react with silver so if it's silver plated a drop of HCl will not react with it --- if it's tin plated the HCl will dissolve it exposing the copper or brass under the tin

Kurt


----------



## kurtak (Dec 30, 2021)

snoman701 said:


> High end copper cookware is regularly plated with tin.
> 
> It's wear is expected, and regular retinning is an expected expense.



Interesting snoman (& Justin) - I just always assumed it was chrome plating for the above reasons

Thats what I get for assuming - LOL

Thanks for setting me straight 

Kurt


----------



## snoman701 (Dec 30, 2021)

kurtak said:


> Interesting snoman (& Justin) - I just always assumed it was chrome plating for the above reasons
> 
> Thats what I get for assuming - LOL
> 
> ...


i had no clue until i found someone local who was making a batch of tin plated copper pans. they were pricey! 

Not something you buy at bed bath and beyond, that is for sure.


----------



## justinhcase (Jan 1, 2022)

kurtak said:


> Interesting snoman (& Justin) - I just always assumed it was chrome plating for the above reasons
> 
> Thats what I get for assuming - LOL
> 
> ...


I know, all my pot'sand pans are stainless steel.
But one of my fist jobs way back when was at a place called the Victoria Hotel in Sidmouth.
I started off as a KP and worked my way up to the assistant saucey.
Quite a good education in the bottom line. The five French mother saucesm, béchamel, velouté, Espagnol, hollandaise, and tomato.
Pluses basic understanding of a wine and cheese cellar.
But Mr Clarvay did insist on using traditional copper pot's and pans.
He held that for a good sauce to caramelise it is important to hold an even temperature, and for the price they charge at the Victoria they could cook in gold.
I have to admit, I still do as he told me, and it tastes very good every time.
Though I have to use S.S. not £100 a time copper pans.


----------



## nickvc (Jan 2, 2022)

The one point I will make is that if you do intend to use the nitric sulphuric process it’s normally done hot and with concentrated sulphuric in the mix not something I would want to be doing, the fumes will be dangerous and then you have hot sulphuric


----------



## Cryogaijin (Jan 2, 2022)

kurtak said:


> Are you sure the silverware (knives/forks/spoons) are stainless steel ?
> 
> I ask because SS silverware is rarely if ever plated with silver


Yup. Labeled "plated stainless steel" on the spoons. By the look of it, is 50+ year old Oneida.


----------



## Yggdrasil (Jan 2, 2022)

Cryogaijin said:


> Yup. Labeled "plated stainless steel" on the spoons. By the look of it, is 50+ year old Oneida.


Plain nitric will work if that is the case.
Much simpler.

But, are there such a thing as stainless plating?
Hard to believe, but who knows?


----------



## justinhcase (Jan 3, 2022)

Yggdrasil said:


> Plain nitric will work if that is the case.
> Much simpler.
> 
> But, are there such a thing as stainless plating?
> Hard to believe, but who knows?


They gold plate stainless steel quite a lot in watch bands.
So I suppose you can plate it with anything you want.


----------



## Yggdrasil (Jan 3, 2022)

justinhcase said:


> They gold plate stainless steel quite a lot in watch bands.
> So I suppose you can plate it with anything you want.


Plate stainless, yes.
But put stainless plating on something, is that possible? 
Since it is an alloy and all?


----------



## justinhcase (Jan 3, 2022)

Yggdrasil said:


> Plate stainless, yes.
> But put stainless plating on something, is that possible?
> Since it is an alloy and all?


I think electroplating normally will only allow you to deposit 'Fe' atoms without any of the other elements needed to give Stainless steel its properties.
But there is a method for plating stainless steel with a Fe-25Ni-16Cr alloy which uses electroplating. The results from the article give a maximal electroplated layer thickness of 23 um. The properties of the electroplated alloy seem to be of similar quality to their reference sample of SAE 316 stainless steel. Electroplating stainless steel onto substrates is challenging, specifically due to the required element chromium, which gives stainless steel its resistance to oxidative degradation. It is evidently difficult to create a stable, three element solution of Fe, Ni, and Cr due to the lack of a well-developed chemical complex for delivering chromium to the cathode.


----------



## Yggdrasil (Jan 3, 2022)

Just curious


----------



## Cryogaijin (Jan 5, 2022)

Been running the tap-water electrolytic deplater for aboot 4 days. Seems to be working well, and the platter I'm working on is about 50% deplated. It is taking this long mostly due to inefficient prototype setup. . . now that I've determined it should work I can work on making it more efficient. Also the platter I'm deplating looks like it will be awesome in pure copper. . . it appears to be maintaining most of the engraved detail.


----------



## Cryogaijin (Jan 23, 2022)

Still refining my process, but I have just shy of 4oz of copper contaminated silver. 

Currently my biggest issue is Zinc. My first deplating was Silver on Copper, and went great, ended up with 2.15 troy ounces of pretty shiny silver. Next one was silver on pretty low quality brass, and ended up with a TON of zinc contamination. Total PITA. So question for y'all: Is there something that'll dissolve zinc, but not copper or silver?


----------



## Yggdrasil (Jan 23, 2022)

Cryogaijin said:


> Still refining my process, but I have just shy of 4oz of copper contaminated silver.
> 
> Currently my biggest issue is Zinc. My first deplating was Silver on Copper, and went great, ended up with 2.15 troy ounces of pretty shiny silver. Next one was silver on pretty low quality brass, and ended up with a TON of zinc contamination. Total PITA. So question for y'all: Is there something that'll dissolve zinc, but not copper or silver?


Muriatic or even Sodium Hydroxide will dissolve Zinc.
And since Muriatic without oxidizer won't dissolve neither silver nor copper, it should be safe.

If you dissolved the Silver in nitric you will need to roast it before adding Muriatic. There will be a brief moment with AR if not.
Regards Per-Ove


----------



## Cryogaijin (Jan 24, 2022)

Interesting. So I chopped up a silver plated brass plate, and doused it with HCl on a hotplate, with agitation. Let it sit all day, and after 8 hours much of the silver plating had flaked off, the rest was nice and shiny with all tarnish dissolved away. Unfortunately the rest of the silver was protecting the brass from losing its zinc. . . 
I'm going to have to experiment. If I can get HCL to cause all the plating to flake off, that might be a way to get through all this plated stuff.


----------



## Helian (Jan 25, 2022)

Refining silver in solution is very easy, as long as it's not contaminated with lead or mercury. Add table salt in solution or HCl and the silver will drop as silver chloride. Decant the liquid a few times until all that's left is the silver chloride and water. Then add one part in 20 sulfuric acid, a bunch of zinc plated roofing nails, and stir for about half an hour. The silver will cement out in pure form. Decant until there's nothing left but silver, water, and the nails, remove the nails with a strong magnet, and thoroughly dry the silver over a hot surface of some kind.


----------



## Cryogaijin (Jan 29, 2022)

kurtak said:


> Are you sure the silverware (knives/forks/spoons) are stainless steel ?


I processed this today with my first use of Nitric. Plated went in, VERY shiny stainless steel came out. The silverware was stamped "National Stainless Japan" If I encounter any more, I'll have to snap it up, as the resultant stainless steel silverware looks brand new. (Not sure what type of stainless they are, but they're strongly magnetic) 

I did mess up one thing though: I also threw in some plated magnetic baby silverware that turned out to be normal steel, which made everything quite a bit harder to deal with. But I have some copper sitting in the filtered solution presently, and will throw some steel in once all the silver is removed. I'm also planning on running my 4.5 troy ounce ingot through nitric tomorrow, to separate the silver from the copper. I may film this, as my GF and parents are interested to see what I'm up to. (I'm planning on making my GF a necklace with the silver, and gilding the bronze axes I'm forging for her with it.) 

I'm very clearly spending more $ on this than I'd "get out" of it, from a purely financial POV. But I'm having fun and learning, which was the point in the first place. (As I mentioned in my initial post on the forum, I prefer copper to silver and especially gold. To me, the only value gold has is in producing unusual alloys.) 

On the other half of this project (Deplating non-stainless steel stuff) most of the handles are made of plated Tin (or some other soft, low melting temp grey metal. Don't THINK it is zinc, as I haven't produced any zinc oxide off it.) Anyone know a good way to extract silver from Tin? 

Finally, I'd be interested in refining nickel from the EPNS items I have (Roughly 100kg at this point. I swear it is breeding in my garage) any pointers or resources on nickel refining? I'm mostly interested in using it for nickel-plating, which will potentially replace a bunch of damaged chrome plate on a car I am restoring.


----------



## ssharktu17 (Jan 29, 2022)

Cryogaijin said:


> I processed this today with my first use of Nitric. Plated went in, VERY shiny stainless steel came out. The silverware was stamped "National Stainless Japan" If I encounter any more, I'll have to snap it up, as the resultant stainless steel silverware looks brand new. (Not sure what type of stainless they are, but they're strongly magnetic)
> 
> I did mess up one thing though: I also threw in some plated magnetic baby silverware that turned out to be normal steel, which made everything quite a bit harder to deal with. But I have some copper sitting in the filtered solution presently, and will throw some steel in once all the silver is removed. I'm also planning on running my 4.5 troy ounce ingot through nitric tomorrow, to separate the silver from the copper. I may film this, as my GF and parents are interested to see what I'm up to. (I'm planning on making my GF a necklace with the silver, and gilding the bronze axes I'm forging for her with it.)
> 
> ...


Interesting how much silver you get per piece on the stainless/silver pate?


----------



## Cryogaijin (Jan 29, 2022)

ssharktu17 said:


> Interesting how much silver you get per piece on the stainless/silver pate?


Individually very little. Forks had the most, followed by big then little spoons. I did about 2dozen, and I expect perhaps a gram each once everything is dry.


----------



## ssharktu17 (Jan 29, 2022)

Cryogaijin said:


> Individually very little. Forks had the most, followed by big then little spoons. I did about 2dozen, and I expect perhaps a gram each once everything is dry.


Always thought spoons had more more surface area. That does seem pretty low I guess it’s probably not a heavy plating.


----------



## jakospence (Mar 6, 2022)

justinhcase said:


> I would not try and recover the silver conventionally.
> But I would use it as sacrificial copper in silver recovery.
> That way you do not waste any acid and still retain all metals of value.


I’ve never heard this strategy before, but it’s brilliant. Thank you for sharing!


----------



## Rreyes097 (Nov 23, 2022)

Cryogaijin said:


> I live near a Goodwill "outlet" store. For those only familiar with normal Goodwills, the outlets are full of bins of mixed "junk" that wasn't purchased from the normal Goodwill stores. I frequently see silver plated copper serving dishes going through the bins, and have started snagging them for their copper value. (Purchases over 25lbs are only $1.50 a lb, so about a third the spot price for copper. Good deal for me.) I haven't done much with silver thus far, but I'm curious if there is a reasonable way to extract the silver, or if I should just leave it in the copper ingots I'm making? Would the tiny amount of silver contamination in the copper impact the quality of bronze or brass made from it?


Wow where are these Goodwill outlets located? I've never heard of them


----------

