# Melting Cemented Silver



## Shrek (Sep 24, 2013)

Hey all,
Sorry to start a new thread, but I didn't want to go off-topic on the last one.
I'm reducing fixer using zinc (as is recommended in Hoke's Refining Precious Metal Wastes). I've done everything by the book, and I have silver sludge that looks as it should.
The problem I'm having is with the melting process; trying to turn my sludge into solid metal silver. Here's what hasn't been working:
- heat up a small melting dish using a propane torch.
- sprinkle a small amount of borax all over the melting dish, continue heating.
- put some sludge into the melting dish and heat.

This hasn't really worked out for me.  I've ended up with what basically look like black stones that won't turn liquid. What am I doing wrong?


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## element47.5 (Sep 24, 2013)

Mere propane doesn't have enough poop to melt silver; minimally, you need MAPP gas and a turbo torch. I do not think you'll be able to melt anything bigger than a pea sized button of silver with straight propane, and even then, just barely. I don't think you are going to get where you want with straight propane.


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## metatp (Sep 25, 2013)

I've been able to melt over 3 ozt of silver in a melting dish with a propane torch. Though I do live in South Florida. To make this work, I insulate the melting dish with ceramic fiber blanket, 8 lb density.

Tom


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## MysticColby (Sep 26, 2013)

propane/air will only melt silver if it is insulated.
you need fuel/oxygen to melt it without insulating.


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## etack (Sep 26, 2013)

Melting silver with a torch is annoying. Its easy to overheat and burn off your silver too. heat the dish in an enclosed furnace to avoid this.

Eric


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## kadriver (Oct 26, 2013)

I use an oxy/accet torch to melt cement silver.

I use a cutting torch tip and adjust the flame so that there is no noise, no hiss, then go down with the flame a little more.

Then, concentrate the heat on the edge of the melt dish.

I avoid hitting the silver powder directly with the flame, keep the flame pointed at the dish. If the flame is allowed to contact the powdered silver, or even the molten silver, then it will almost instantly begin to boil the molten silver and turn it into vapor - causing loss of the silver!

As the dish heats up, the silver will begin to melt and form a pool of molten silver. Never let the flame contact the silver directly, always concentrate the flame on the dish and keep the tip of the flame moving in a circular pattern around the inside of the dish.

Sometimes the flame gets too close to the metal and white smoke will rise up out of the dish.

This white smoke is vaporized silver being lost as vapor into the air, this is why it is so important to never let the flame touch the silver.

kadriver


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## niteliteone (Oct 26, 2013)

kadriver said:


> I use an oxy/accet torch to melt cement silver.
> 
> I use a cutting torch tip and adjust the flame so that there is no noise, no hiss, then go down with the flame a little more.
> 
> ...



Not to mention when the silver boils it throws thousands of tiny balls of silver up to 2 feet away from the melting dish.
Don't ask how I know this. :shock:


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## kadriver (Oct 29, 2013)

etack said:


> Melting silver with a torch is annoying. Its easy to overheat and burn off your silver too. heat the dish in an enclosed furnace to avoid this.
> 
> Eric



I am considering buying a small electric furnace for melting silver, any suggestions on which type and brand is best suited for this?

kadriver


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## Lou (Oct 29, 2013)

Kevin,

I advise against melting silver with an electric heating element furnace (unless you have atmosphere control). If you do, Kerr or Electrotherm make little resistance furnaces that'll melt about a kg of Ag.


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## kadriver (Oct 30, 2013)

niteliteone said:


> Not to mention when the silver boils it throws thousands of tiny balls of silver up to 2 feet away from the melting dish.
> Don't ask how I know this. :shock:



I keep a 4 inch paint brush and small dust pan at my melting station to sweep up these tiny balls and save them for refining later. No matter how careful I am with the torch, inevitably the flame does contact the silver and throws these tiny balls everywhere.


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## kadriver (Oct 30, 2013)

Lou said:


> Kevin,
> 
> I advise against melting silver with an electric heating element furnace (unless you have atmosphere control). If you do, Kerr or Electrotherm make little resistance furnaces that'll melt about a kg of Ag.



Thanks Lou, I don't have atmosphere control. Maybe I'll build a small propane furnace for melting silver.

kadriver


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## etack (Oct 30, 2013)

kadriver said:


> Lou said:
> 
> 
> > Kevin,
> ...



That's what I would do. I have a Kerr and its OK but limited to small pours 15-25TOZ
Ag needs more volume

Eric


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