# Silver copper electrical contacts



## PPG4me (Feb 15, 2015)

Hi guys I hope you guys can help me with this. I have a very large quantity of electrical contacts there made up of copper with the contact point being silver. There very difficult to separate them so what I'm looking for is the best process to refine these in quantity.
I'm thinking probably a electro refining but I'm pretty new to this.

Thank you in advance for your help

Brad


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## bswartzwelder (Feb 15, 2015)

Sit back there, cowboy. If you're serious, then you have a lot of work to do. Mostly reading. Do yourself a huge favor and put everything aside until you know exactly what you need to do. That may prevent you from losing values in the long run. As long as your values are safely stored in a box on a shelf, you won't lose any. Start by reading Hoke's book. It's a free download here on the forum. Then read the sections of the forum dealing with safety and waste disposal. Recovering all the silver and gold in the world won't do you a bit of good if you, a family member, or neighbor dies from the fumes or the chemicals you are using.

Many people just like you have jumped in and started experimenting only to make a huge mess that they have to dig themselves out of. In the long run, their mistakes have cost the time, money, and the chemicals which they bought and didn't need. Trust me on this because I speak from experience. The forum is full of posts just like yours from others who have made the same mistakes.

EVERYTHING you need to know to process your contacts is right here. Nobody will sit here and waste they're time repeating for you what they have repeated time and time again for almost every other person who has come here. On this forum, the onus is on you. You want answers? Then you must be willing to show us that you are truly interested in learning about recovery and refining of precious metal whether it be just one metal or a whole spectrum of precious metals by putting forth the effort to learn the various processes and how they work.

While you're at it, read the announcements section which is usually found at the top of every forum section. It is there for a reason. Those in control of the forum (certainly not me) do not like abusive language, foul language, texting lingo, or for that matter posts written in all caps. It is considered shouting, and is not acceptable. Also, be as precise in your writings as possible. Although they are spelled almost the same, there is a huge difference between sodium metabisulfite and sodium metabisulfate. If you are trying to precipitate gold from a solution, one will work and one simply will do nothing.

Welcome to the forum. Pictures are nice as well. You say you have a very large quantity of these silver copper electrical contacts. To me, a pound would be a lot. To others on the forum, a couple of tons would be a lot. Don't expect more than what is reasonable. A pound of AMC CPU's for example will not yield a pound and a half of gold. Nor will it yield a pound of gold, or even a half pound of gold. If your lucky and do things right, you might get 1.1 grams of gold.

If you're serious about recovering silver from your contacts, you've come to the right place. Do some reading and then start asking your questions. All the answers you could ever need are right here, you just have to do a little digging.


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## kurtak (Feb 15, 2015)

There are many kinds of points

can you provide some pictures

Kurt


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## PPG4me (Feb 15, 2015)

Kurt, Thank you for your reply, I've attached a picture of the contact. I've read quite a bit on the subject and was left a little confused on what direction I should proceed I'm hoping that somebody could give me some advice based on their experience. 

Thank you,

Brad


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## kurtak (Feb 15, 2015)

Are they all like that or is that just one of the larger ones ?

& what do you consider as having a large amount ? (how many pounds do you have)

What I am getting at is in order to really help you - you need to provide more info including more pictures

If they are all that type then they are out of magnetic disconnects which tend to be higher yield then a lot of other types

also if you have other types - then depending on the types could make a difference in the processing of the type

When you take pictures put something like a quarter or dime or something everyone will recognize for size comparison in the pic

I do a lot of points so I can help you get started - but I need more info --- its not a one process fits all types thing 

Kurt


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## Smack (Feb 15, 2015)

If your still confused on what direction to go with them, safe to say more reading is in your future. One good day of reading on the subject of silver and contacts here on the forum should leave you with the knowledge of how to proceed.


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## Emporio (Feb 15, 2015)

I saw this video on YouTube the other day, with a guy separating the silver from this type of contacts.

[youtube]http://www.youtube.com/watch?v=EThbWRbfSIE[/youtube]


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## PPG4me (Feb 15, 2015)

Kurt, Thanks again I certainly appreciate your input. Here is an additional picture all of them are one of these two types. I have just a little under 40 pounds of these contactors but I have a source for more not sure how fast they'll accumulate but somewhere in the order of a pound or two a month for sure. 

Emporio, great video thank you very much.

Brad


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## pimpneightez (Feb 16, 2015)

I use a B-tank and some heat. Most of the time they come off rather quickly. The ones that don't come off I put in another pile and use an oxy-acytelene set-up. This needs a little more attention because off the high heat and tendency to melt the silver if it gets too hot. I put them in a vise to hold them with a bucket off water below. then as it gets hot enough a flat head to boink them off like a tiddly wink.


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## kurtak (Feb 16, 2015)

Brad

First of all I see you are a new member so you really do need to spend some considerable time doing research here on the forum especially about safety & waste treatment because you are in fact dealing with hazardous & toxic stuff at every step of the way here --- the dangers & waste created is something that youtube videos & other info on the net never informs the watcher/reader of --- you should also down load & read Hokes book which you will find here :arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=54&t=19798

Those points should run "about" 20% silver (+/-) & about 80% copper (+/-) Which means that at 40# of contacts you should have "about" 8# silver (+/-) after you de-solder the points off the copper bus bars

de-soldering the points (also called sweating off) is the first thing you need to do (& it is the first place you meet an element of danger due to the cadmium in the solder which vaporizes at a low temp producing "toxic" fumes - cadmium poisoning is very much like mercury poisoning) so you need to at the very least do this outside - wind at your back & wear a good cartridge type respirator (not just a dust mask)

You can do it with a torch - a point at a time (in the video it looks like they are using induction heat) but with 40# it will take you about a week to get it done & you will go through a HUGE amount of gas --- Mapp gas &/or acetylene will cost you a fortune - you would be better off with a oxy/propane torch set up

So you really need to have a set up something like this :arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?p=218360#p218315 with this set up you could do 40# in a day to day & a half & only use about 1/4 the gas it takes with a torch

Then you follow the 50/50 nitric/distilled water instructions (as in the video) to dissolve the points (which still have cadmium solder on them) followed by the cementing process with copper

It will take "about" 1 gallon of 68%/70% nitric to dissolve 8# of silver (it may take a little more due to base metals in the solder &/or alloy of the points)

Depending on drag down of base metals the cementing process will give between 95% & 98% silver so if you are going for 999 plus silver it will then need to go through the silver cell for real refining

The brown fumes coming off the reaction vessel when dissolving the points are Nox fumes - very toxic & NO cartridge filter type respirator will filter them out

When you first dissolve the points (8#) you are going to have 2 gallons solution (1gal nitric & 1gal D-water) before you start the cementing process you want to dilute that to 3 times volume with more D-water (ad 4 gal D-water) so you now have 6 gal solution

When the cementing process is done you then decant (or siphon off) the solution - then wash/filter out the solution trapped in the silver cement - by the time you are done with that your starting 2 gallons of solution will have become something like 10 (if your lucky & have a vacuum filter set up) to 15 gallons of solution (if you don't have vacuum filter set up) --- this is toxic waste containing heavy metals - mostly copper but cadmium & other as metals as well

The waste solution "must be treated" to rid it of heavy metals - you "can not" just dump it :!: 

To treat the waste - you want to use iron to cement out the copper & other base metals (just like cementing out the silver with copper) 

Once the copper & other base metals are cemented out with iron - you now have a solution that contains much iron - this iron then needs to be removed - to do this you can ad lime to it which will drop out the iron (it takes a few days to drop the iron with stirring to keep the reaction of the lime in the solution going)

Also - when cementing out the base metals & doing the lime treatment it will go better if you evaporate the solution back down to 6 gallons (or at least 7 - 8 gallons)

Also - when cementing large volumes of solution like this (including your silver solution) it is best if you provide some kind of agitation --- this can be done with stirring or you can use an air bubbler set up

Once you are done with all that you still need to melt it all - which you can do with a good MAPP gas torch & melting dishes - but you can only do about 2 - 3 ozt at a time this way (& 8# silver is 115.25 ozt) so a lot of time & MAPP gas

so really when working with this much metal you really need a gas furnace set up like this :arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=49&t=21409&hilit=smelting+furnace#p220999

With this furnace set up you can pour 2# silver bars (actually bigger but thats what I pour) & have your 8# silver done in a couple hours

Kurt


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## PPG4me (Feb 16, 2015)

Kurt,

Wow, you went way out of your way to help me I didn't expect this kind of response thank you very much. Thank you for your safety suggestions, I will read hocks book.

Hopefully someday I can help somebody on this forum as you helped me.

Take care and thank you again.

Brad


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## ssabovic (Feb 17, 2015)

HI ,
SOME OF SILVER CONTACTS CONTAIN CADMIUM SO YOU HAVE TO BE CAREFULL , THAT CAN EFFECT YOUR HEALTH WHEN YOU HEAT IT UP.


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## butcher (Feb 17, 2015)

ssabovic,
Your warning is important and should be emphasized, but posting in all capital letters is frowned upon on the forum.


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## kurtak (Feb 17, 2015)

kurtak said:


> de-soldering the points (also called sweating off) is the first thing you need to do (& it is the first place you meet an element of danger due to the cadmium in the solder which vaporizes at a low temp producing "toxic" fumes - cadmium poisoning is very much like mercury poisoning) so you need to at the very least do this outside - wind at your back & wear a good cartridge type respirator (not just a dust mask)
> 
> Kurt



& if you read my post you will see I already made a point of the danger of cadmium poisoning including underlining that point in my OP

Kurt


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## kurtak (Feb 17, 2015)

ssabovic said:


> HI ,
> SOME OF SILVER CONTACTS CONTAIN CADMIUM SO YOU HAVE TO BE CAREFULL , THAT CAN EFFECT YOUR HEALTH WHEN YOU HEAT IT UP.



Only "some" points have cadmium in them as part of the contact alloy - but most all of the solder(braze) has cadmium in it - so the solder should always be considered a cadmium hazard

Kurt


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## Alegiance (Mar 6, 2015)

hi *kurt* you write 

Those points should run "about" 20% silver (+/-) & about 80% copper (+/-) Which means that at 40# of contacts you should have "about" 8# silver (+/-) after you de-solder the points off the copper bus bars

what it mean "40#" ? 40 $ or 40 gramm ? :roll: 

:arrow:


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## FrugalRefiner (Mar 6, 2015)

I'm not Kurt, but I can answer the question. # is a symbol used in the United States to mean pounds. 40# means 40 pounds, which would yield 8 pounds of silver.

Dave


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## Long Shot (Mar 6, 2015)

Hi Brad. I also collect these. The advice given is good, it is a little time consuming but if you have 40 lbs and a continuing source then you need to remove the points by higher heat, i.e., acetylene or oxy acetylene torch - they come off quick and you will have one hell of a pile of good stuff to work with. The more base metal (copper in this case) the more expensive acid you will waste separating the silver from the copper - it takes 5 times the nitric acid to dissolve copper versus silver. The advice about Cadmium is something you REALLY need to consider, it is nasty, do your work in a well ventilated area and away from anybody, protect yourself from the fumes. There is plenty of info on what you need to do next and you REALLY need to read up and be prepared for how you are going to do it, how you are going to recover your silver and how you are going to deal with your waste in a responsible manner. I would advise you to build your stash and be totally prepared for the next step - you will need nitric acid, decent glassware, PPE, and a decent source of copper to precipitate. Please read all you can before using any of it.

JB


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## Harold_V (Mar 7, 2015)

Long Shot said:


> you will need nitric acid, decent glassware, PPE, and a decent source of copper to precipitate. Please read all you can before using any of it.


The needed copper is already in his possession. The buss on which the silver contacts are soldered are more than adequate for recovering silver, with the added bonus of recovering the traces of silver solder that is not removed with the contacts. 

Harold


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## nickvc (Mar 7, 2015)

As Harold pointed out you already have the copper on hand and as a bonus you can use the whole points to cement your solutions recovering the silver for free.


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## Long Shot (Mar 7, 2015)

Of course Harold, duh on my part!


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## Alegiance (Apr 3, 2015)

hehe What you meam Toxic fumes at Low Temp ?

if i keep my silver contact in a metalic bowl ?

is there a risk of Toxic fume by 20 or 30 celcius degree ?

:roll:


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## bswartzwelder (Apr 5, 2015)

Many years ago when I worked for a major electrical equipment manufacturer, we made circuit breakers for use by the electrical power industry. These circuit breakers ranged from a couple of thousand volts up to more than a half million volts. Current ranges were from a couple hundred amps up to about 6000 amps if my memory serves me correctly. Depending on the model of breaker many of them had contacts which had a tip brazed onto the copper. One day, I picked one of the tips out of the scrap and gave it to a friend who thought it might contain massive amounts of silver. 

He told me that upon heating, the silver in something of this nature would migrate towards the heat. Never did say why, but I suspect he just plain didn't know since he was not scientifically minded. He heated up the tip with an oxy-acetylene torch. Sure enough, there was a small (very small) button which showed up and he claimed was silver. Out of a tip which may have weighed a pound or two, he got maybe a fourth of an ounce. He then hit the tip with all the heat his torch could put out. Nothing happened except maybe it started to glow red due to the heat.

Since there wasn't enough silver to make extracting it profitable, we gave up. I'll bet the braze used to hold the tip onto the conductor had more silver than the massive contact tip since the braze was approximately 50% silver. Always wondered what the base metal in that contact tip was. I suspect it might have been tungsten because of the tremendous heat generated when the contacts opened. The quenching medium in the circuit breakers was either oil (which kind of exploded) when the breaker opened, thus blowing out the arc or sulfur hexafluoride gas. The gas breakers eventually became more popular because of oil shortages in the 1970's and the fact that the gas was a much better insulator (electrically) than the oil.


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## kurtak (Apr 8, 2015)

bswartzwelder said:


> One day, I picked one of the tips out of the scrap and gave it to a friend who thought it might contain massive amounts of silver.
> 
> He told me that upon heating, the silver in something of this nature would migrate towards the heat.
> 
> ...



Sorry for the delay in responding to this but my computer was down for a couple days

Anyway yes those contacts were most likely tungsten/silver (considering the application) & should run between 30 - 40% silver - so at a pound or two should have had 4.35 - 5.8 ozt silver per pound

The problem was that trying to heat them the way he did he only got a small amount of the silver (near the surface) to migrate out

The only real way to get the silver out of them is to leach it out by boiling them in nitric acid for an extended period of time (which can be done in a SS pot/kettle)

Being that large you would most likely need to pull them out of the nitric leach a few times & chip the tungsten away (about every 4 - 6 hours) & it would likely take at least 2 or 3 days

As a note - this is done with a low simmer type boil

Kurt


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## bswartzwelder (Apr 8, 2015)

Thanks, Kurt.

I am no longer in a position where I can get hold of these little gems. Sounds like putting them into a Crock Pot on low heat for a while might have worked, except I don't think Crock Pots were on the market yet.

The engineers at that place said that in oil filled circuit breakers, as the contacts started to separate, oil rushed in and the intense heat of the arc caused a small explosion which blew out the oil and the arc. Some of these circuit breakers required 3 or 4 railroad flat cars to ship them out to the customer. Most of the higher amperage unit had 2 or 3 sets of contacts per pole. Upon initiating an open sequence, the main current carrying contacts would open first and then several milliseconds later, the arcing contacts would open. By doing it this way, the silver plating on the main current carrying contacts would be mostly undamaged and the arcing contacts took the beating if being destroyed in the process. However, these large breakers seldom operated once in service, unless there was a fault on the line somewhere.


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