# Silverplate separation



## Pilgrim2850 (Jun 15, 2008)

Good day everyone,

I've been collecting silverplate. I've read on here that silver on copper is considered contaminated copper. I'm bound and determined to separate these someday economically, but I also have silver plated on nickel and on zinc. My question is "is it feasable to recovery the silver from these and what would be the best way to do that?" Thanks a bunch............larry


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## Shecker (Jun 15, 2008)

A 15% solution of nitric acid at room temperature will slowly dissolve silver
and not much of base metals. Filter the solution and produce silver chloride from the solution with table salt. Using NaCl to produce silver chlorides should not produce chlorides of base metals except lead. Lead chloride can be washed from silver chloride with a solution of hot distilled water and the lead chloride will recrystallize on cooling. The clean silver chloride can be reduced to metal by methods discussed elsewhere on this forum. I react the clean silver chloride with clean iron. This produces a spontaneous reaction in which AgCl + Fe will produce Ag + FeCl. This is really cool to watch. When there is no more silver to reduce the reaction stops. Take out the iron, wash the silver free of FeCl, and dry. You now have silver metal.

This is another passive system that can be done in a five gallon bucket while you go fishing (or whatever).

Randy in Gunnison


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## Harold_V (Jun 15, 2008)

Shecker said:


> A 15% solution of nitric acid at room temperature will slowly dissolve silver


Randy, I'm curious how you have addressed the following:

The problem with this suggestion is the fact that the moment base metal is exposed, silver will be reduced on the base metal. Items rarely strip uniformly, so there are points that develop that will start reducing dissolved silver. It is difficult to remove only the silver for that reason. In the end, to effect good extraction, all of the base metal must be dissolved---which makes the operation a losing proposition. The value of the recovered silver is less than the value of the base metals that could have been sold as scrap, and a large amount of nitric acid will have been consumed. 

As it has been previously stressed, there are no known _economical _ways to recover silver from plated objects. Stripping in a sulfuric cell would likely come as close as you can get. 

There is a parallel between the above process and the one of using AR to recover gold. With rare exception, neither are a good idea.

Harold


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## Shecker (Jun 15, 2008)

My experience (I've done a little of these things) is that the silver will re-precipitate on the best metal but it does it like using copper to reduce silver nitrate. It is not a dense adherent coating. It can be washed off with a vigorous spray of water and there is still silver in solution. Have a great day.

Randy in Gunnison


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## Anonymous (Jun 15, 2008)

Melt some zink, swirl the cut up pieces in it until the silver is dissolved off, then, process the zinc. At least that is what I would try. I have some zinc and some plated stuff so I may test one of these days.


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## Harold_V (Jun 16, 2008)

Shecker said:


> My experience (I've done a little of these things) is that the silver will re-precipitate on the best metal but it does it like using copper to reduce silver nitrate. It is not a dense adherent coating. It can be washed off with a vigorous spray of water and there is still silver in solution.



In the course of refining for over 20 years, I tried that as well. My experience convinced me that it was a fruitless effort. Not all of the silver could be recovered from the plated object without dissolving it virtually completely. I found that once a large area of base metal was exposed, things went downhill quite quickly. That's why I made my inquiry. I never managed to find a system that would be selective enough to make it worthwhile. I found the same thing to be true when stripping gold from brass or copper with cyanide, assuming it didn't have a nickel barrier under the gold plating. While uncommon, it did exist. Once the precious metal layer is perforated, the solution attacks the base metal with vigor---eventually stopping dissolution of the values completely. 

I agree---if you are comfortable in recovering a percentage, the system works, but leaves a great deal to be desired. 

Harold


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## Shecker (Jun 16, 2008)

This is just like mining. There is no way to get it all. But there is an economical level at which silver can be recovered. Some will be lost.
One has to figure the percentages.

Randy in Gunnison


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## jaun (Jul 5, 2008)

A good method I use to separate silver contact points from the base metal back plates, is to process it with AR. It dissolves the base metals, leaving the silver. It will work for plated also. But like Harold said I don’t think it’s worth it, if there is too much base metal, you will use too much acid, and if acid is expensive in your area it won’t be feasible. And in most cases the silver has to be processed further to purify.


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## Harold_V (Jul 5, 2008)

I processed a lot of silver contacts when I refined. I usually removed the contact from the buss with a torch, then used the buss to recover silver from silver nitrate. That way, all the traces of silver that were left behind in the form of silver solder got processed for full recovery of the silver. It was an excellent source of copper for the purpose. 

As was suggested, removing the base metal with acid isn't a great way to go---especially if nitric is difficult (and expensive) to obtain, and it generally is in most cases. 

Harold


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## jaun (Jul 6, 2008)

Yes I agree with you 100%, that is the exact same way I use for the silver contacts you mentioned.

I was referring to the small silver contacts on relays (tele com and so on). They are punched through thin nickel silver or copper plates. Many of the old telephone exchanges we took out contained several Kg of silver. We would cut the points off with a side cutter and process with AR to get rid of the back plate. We then sold the points to a refiner. The points were quite pure, ran about 98% silver.


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## goldsilverpro (Jul 6, 2008)

The only way I ever found to economically recover plated silver, without attacking the copper, was an electrolytic system using a solution containing about 6 oz/gal sodium cyanide and 12 oz/gal sodium hydroxide. The high NaOH prevented the copper from being attacked. The dissolved silver plated out on passivated stainless cathodes.


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