Silver, In Old Blowout Circut breakers.

[SilverFox]

Old Circuit breakers brands such as Northern Pacific, And Livernois contain solid** silver buttons. I estimate these Circuit breakers were manufactured around the 1980's. Each breaker contained two silver contacts.

The square contacts came from the Northern Pacific, the round from the Livernois brand breaker.

** the Copperish color on some of the buttons are remains of the brazing that was use to mount them as contact points.


** I have not yet tested for purity

 

[Barren Realms 007]

Who makes the Livernois breaker? Never herd of that company. What size breakers were they?

 

[butcher]

circuit breakers will usually contain other metals,look for them, I just posted some of the metals to look for on another post today. if high current type tungsten (W) is usually involved, as a hardener, usually the flat waffle types.

 

[AlanInMo]

Here's a link to the post that "butcher" mentioned, good info --> http://goldrefiningforum.com/phpBB3/viewtopic.php?p=52188#p52188

 

[butcher]

thanks Alan, couldn't remember where, my mind or memmory not that good.

Looks like Allen Bradley may have made the livernoise. or the noisy liver circuit breaker? http://www.google.com/search?hl=en&q=allen+bradley+livernois+circuit+breaker&aq=f&oq=&aqi=

 

[SilverFox]

Ok, those breaker contact points will not melt at the correct temp. Silver has a melting point of 1800 degs which is lower than gold, but these contacts refuse to melt under direct flame of my map torch, which melts gold perfectly.

Anyone have any Ideas? I was going to dissolve some in a lil nitric, but my stannous wont be ready till morning.

 

[patnor1011]

tungsten

 

[qst42know]

Sintered tungsten (much like a bronze fuel filter) impregnated throughout with a silver alloy. Circuit breakers have to withstand a great deal of heat.

 

[butcher]

tungsten used so they don't burn up contacts with arcing when swithching High current electrical loads,

tungsten has a high melting point.

what I have been doing with them is add them with allot of other contact points, silver and the other metals involved, I melt this lot with some borax, soda ash, add some silver brazing solder to the melt (the phosphorous helps the melt), tiny bit kno3, once melted (the tungsten ones may not melt that well or at all), I pour out on a cold iron welding table top, I have (sooting area of my table with my torch no oxygen flame the acetylene flame leaves a nice layer soot), pouring my silver into sort of a long bar, let cool some, then run wire brush to clean up some, then I take a piece of silver brazing solder, heat end of bar almost to melt and solder on piece of brazing rod, letting cool, with rod still stuck to bar, this then is bent to a hook (sometime rod gets hard so heat), this so bar can hang from lip of a jar and bar will be down in acid electrolyte, using copper nitrate for a dilute electrolyte, the silver bar you made for an anode, positive, and an old silver plated spoon(or other object) as the cathode, power supply a 12 volt battery charger, the charger goes to my small lead acid battery (charging it) them a wire from positive of battery to a tail lamp one terminal the other terminal of this tail lamp goes to the anode silver bar you made,this Series lamp acts as a current limiter regulator, and indicator, telling you how much current is flowing in the cell, from your spoon a wire to negative of battery, bubbling action of cathode is also a good indicator to the action.
now you have an electrochemical recovery cell. this will break your anode to powders which can then be attacked easier with acids later, the electolyte need to be kept somewhat acidic, and cleaned out about once a day, you will see what it needs.

there are many other way's to deal with tungsten points also, they are hard for acids to attack, strong peroxide and HCL will attack them although somewhat slowly.

 

[Harold_V]

Ok, those breaker contact points will not melt at the correct temp. Silver has a melting point of 1800 degs which is lower than gold, but these contacts refuse to melt under direct flame of my map torch, which melts gold perfectly.

Anyone have any Ideas? I was going to dissolve some in a lil nitric, but my stannous wont be ready till morning.

You don't need stannous for silver, nor will it do anything meaningful for you. What you use is Schwerter's, which is nitric acid, distilled water and potassium dichromate. You get a blood red reaction from silver.

The contacts you describe likely are either just tungsten, or a powder tungsten/silver composition, as has already been mentioned.

Tungsten is a rather dark gray color, impossible to mistake for silver, which is the whitest of all metals. It is also very heavy, rivaling gold in specific gravity.

If you test a contact with Schwerter's solution you can expect the contact to react red, even if it's make of tungsten and silver. If you find it does, they can be successfully processed by prolonged boiling in dilute nitric. It takes a little time for the acid to penetrate the contacts, but it does happen. I used to process some that were an inch square and 1/8" thick. They yield under 50% silver, due to the specific gravity of tungsten.

There should be a ready market for the remaining tungsten. It generally brings $5/pound, or greater, although a great deal will depend on finding the right market. Selling spent tungsten carbide inserts for machining has a ready market. Contacts that have been leached may not have.

Harold

 

[Llew]

You don't need stannous for silver, nor will it do anything meaningful for you. What you use is Schwerter's, which is nitric acid, distilled water and potassium dichromate. You get a blood red reaction from silver.

The contacts you describe likely are either just tungsten, or a powder tungsten/silver composition, as has already been mentioned.

Tungsten is a rather dark gray color, impossible to mistake for silver, which is the whitest of all metals. It is also very heavy, rivaling gold in specific gravity.

If you test a contact with Schwerter's solution you can expect the contact to react red, even if it's make of tungsten and silver. If you find it does, they can be successfully processed by prolonged boiling in dilute nitric. It takes a little time for the acid to penetrate the contacts, but it does happen. I used to process some that were an inch square and 1/8" thick. They yield under 50% silver, due to the specific gravity of tungsten.

There should be a ready market for the remaining tungsten. It generally brings $5/pound, or greater, although a great deal will depend on finding the right market. Selling spent tungsten carbide inserts for machining has a ready market. Contacts that have been leached may not have.

Harold

Thanks Harold I appreciate the through explanation. Well done.