Silver ore processing?

[Cbrux7171]

Hey there,

I have about 20lbs of rich silver ore and I am curious about how to concentrate my ore down without the use of nitric acid. The ore has other metal in it(nickel and cobalt), my thought pattern is:

1. Crush rock down to 100 mesh

2. Soak the crushed rock in HCL to remove nickel, cobalt and anything else that will dissolve.
( Does using HCL on silver this fine create any problems)

3. Wash and dry remaining concentrates
( Would a roast be beneficial at this point?)

4. Mix concentrates with flux in 1-2 ratio concentrate to flux and melt in furnace

5. Pour into conical mould, let cool and remove flux

This is just a small breakdown of my thoughts on how to concentrate my silver, I know it will not be pure after this process, I just want to get it concentrated into metal chunks for storage and the next process.

Thanks

 

[butcher]

First I would want to determine what type of silver ore it was (chloride)(sulfide)...Or what else it contained like arsenic...
Knowing the type of ore before developing a plan of recovery.

HCl will convert the silver powders to chlorides, at least what it is exposed to, lead would also form a chloride, any arsenide in the ore would produce arsenic gas...

You would not want to incinerate silver chloride, the silver would also go up in smoke.

 

[Cbrux7171]

Thanks for the reply,

The ore is from cobalt Ontario, so I believe it is pure silver metal with cobalt arsenide, silver arsenide and nickel arsenide

So I would avoid the hcl wash on my 100 mesh crush as it would convert too much silver to silver chloride, thus the silver chloride would burn off in the furnace.

Thanks for the insight!

 

[nickvc]

If you have arsenides present I'd strongly recommend you do not add Hcl as it forms highly toxic arsenine gas...
I would suggest some in depth reading and research before trying to do any processing at all.
No amount of precious metals is worth your health or life.

 

[FrugalRefiner]

The ore is from cobalt Ontario, so I believe it is pure silver metal with cobalt arsenide, silver arsenide and nickel arsenide

There are a couple of threads that have touched on similar ores. See:
Thanks Harold
Caution new members!
Why Can't I Ask a Simple Question and get a Simple Answer?

Dave

 

[Cbrux7171]

Thanks Dave,

Those links are insightful for sure, and those incidences are why I am asking questions before I even attempted to break the rock down. I have been reading as many threads as I can before I do anything because I don't want to get hurt or screw up.

I certainly appreciate the words of wisdom and the info that you all share.

Chris

 

[butcher]

With only 20 pounds of ore, I do not think messing with it would be worth it.
The arsenic can make compounds, or gases and oils with many of the different directions of processing.

With roasting the silver is volatile with the arsenic, so not only are you losing some of the silver but making toxic gases and condensed arsenic compounds wherever the gases go.

With roasting with salt to form chlorides (pre-leach roast), the arsenic not only forms volitile gases with contaminate, but the arsenic can also form chlorides which are water soluble as well as toxic...

And we have cyanide and its dangers, as well the arsenic...

Smelting you have the same dangers and loses.

If you were doing tons and tons of this material and had the money to set up a proper operating facility with safety precautions then I would say try it.

but with a 20 pound rock I say bust the rock up in smaller pieces and sell it a a rock to collectors, and go buy a silver round or two.

The work and dangers are not worth your trouble at this point.

 

[Eu_citzen]

Cobalt, Ontario has some native silver along with mostly sulphides in my experience. There is likely some silver sulphide in there to. I've handled some of the ore; it also can contain Platinum group metals.

It can make nice cut cabochons, if you like lapidary.