# Lead Vs. Nickel for collection.



## NuggetHuntingFool (Jan 12, 2008)

A few questions.

I know that Nickel collects all the Pt groups.

Does it also collect gold and silver?


Has anybody used copper as a collector before?

What are the advantages and disadvantages of lead, copper, and nickel?


Thank you.


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## NuggetHuntingFool (Jan 13, 2008)

Why?


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## Lou (Jan 13, 2008)

Nickel is not only more difficult to dissolve, but it is also about 22 dollars per pound, and thus highly expensive. I've used copper before when making small anodes for electrowinning. 

Lead is cheapest, and is the lowest temperature to use. It has toxicity issues, but is simple enough to use and works very well at dissolving PMs.


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## goldsilverpro (Jan 14, 2008)

F. E. Beamish wrote an excellent series of books on the analysis (all methods are covered) of the noble metals in the '60's and '70's. They include an outline for a fire assay method for the collection of all 6 PGM's using nickel sulfide. The collection is at least as good as when using lead, although neither are as complete as when using the best direct acid extraction methods. Perhaps, the NiS collection can be adapted to a larger scale. Here's Beamish's procedure:

(1) Basic Flux mix for up to 50 g of ore: 60 g of fused borax; 30 g soda ash; 32 g nickel carbonate; 12.5 g powdered sulfur
(2) At a temp. of 1832 deg F., fuse for 75 minutes
(3) Pour into an iron mold. Separate the button from the slag.
(4) Shatter the brittle button in a hydraulic press. Grind until fine.
(5) Overnight, dissolve away the NiS using 400 mL of conc. HCl, at low heat. The PGM's remain as sulfides, which are easily treated with acids.


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## Lino1406 (Jan 14, 2008)

How he avoids sulfur burning?
What he does with H2S from NiS dissolution?


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## goldsilverpro (Jan 14, 2008)

This is an assay procedure, involving small quantities. I'm sure it is well ventilated.


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## NuggetHuntingFool (Jan 14, 2008)

What about copper as a collector?

Just curious...


Also, will nickel, lead, and copper all extract the big three? Au, Ag, Pt (groups)


Which is better for which, or are all three effective if done right?


Thanks


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## Lino1406 (Jan 18, 2008)

Copper collects PGM's
alright, but what than?


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## NuggetHuntingFool (Jan 18, 2008)

Well, I'm no expert.

I'm assuming once the PM's are collected a type of acid is used to dissolve the copper or perhaps even the PM's. Then recovered later.


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## Lino1406 (Jan 19, 2008)

Very complex in any scheme you choose


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