Extracting silver from Galena
Herbert M Sauro
I have a source of Galena (lead ore: PbS + impurities), actually I live
over an old silver-lead mine - or so they say. Now I fancy: 1. assaying
for the silver content; 2. If there is sufficient silver have a go at
extracting some of the silver as silver metal.
Q. How do I go about extracting silver?
Having read through some books, I could try the following (note I only
have access to simple chemical equipment and chemicals - no specs or
fancy organic extractions):
1. Crush the ore as fine as possible
2. Dissolve the ore in Conc HCl or Nitric
3. If Nitric used add HCl to solution and collect precipitate
4. If conc HCl used, dilute and collect precipitate.
According to my book at this stage the precipitate should contain the
chloride salts of Pb, Ag, and Hg (if any).
5. Boil to dissolve any lead chloride, collect precipitate which should
contain any silver
6. If there is any mercury (doubtful) add ammonia to dissolve silver
chloride, filter and discard any precipitate
7. Reprecipitate silver chloride using dilute nitric.
8. So now in theory I have Silver chloride
How can I convert silver chloride to silver metal? The most convenient
method I've come across is to fuse the silver chloride with sodium
carbonate.
If anybody has some bright ideas either to correct the method above or
to suggest a better method I would be most grateful!
Herbert
--
Herbert M Sauro
email: HSa...@fssc.demon.co.uk
Telephone: 01974 282428
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"He who cannot draw on 3000 years is living from hand to mouth" Goethe
"Ah, but a man's reach should exceed his grasp, or what's a heaven for?"
R Browning.
"Uncle Al" Schwartz
Herbert M Sauro wrote:
>
> I have a source of Galena (lead ore: PbS + impurities), actually I live
> over an old silver-lead mine - or so they say. Now I fancy: 1. assaying
> for the silver content; 2. If there is sufficient silver have a go at
> extracting some of the silver as silver metal.
>
> Q. How do I go about extracting silver?
Paracelsus published about the cupel in the early 1500s. It still
works.
In fact, it is preferred as a cheap and easy assay for gold and silver.
Get a current silver quote from your newspaper. Think of it as a hobby
rather than an income stream.
If I were doing this, I'd hide from the EPA, then
1) Burn the galena in air to release SO2 and have lead, lead oxide,
and precious metals remain.
2) Do the cupel. You can take the residual metal to a precious
metals refiner for its gold and silver values. I suppose you could
dissolve the stuff in nitric acid and separate out the individal metals
by controlled potential electrolysis. Or dump the silver as the
insoluble chloride, dissolve in concentrated ammonia, and run it through
a column of steel wool like photographers use to recover silver from
used developer.
Note thst silver salts plus organics like ethanol or acetone have a
remarkable tendency to form silver fulminate and toher touch-sensitive
stuff - BOOM!
--
Alan "Uncle Al" Schwartz
Uncl...@ix.netcom.com ("zero" before @)
http://www.ultra.net.au/~wisby/uncleal.htm
(Toxic URL! Unsafe for children, Democrats, and most mammals)
"Quis custodiet ipsos custodes?" The Net!
M J Pitt
In article <dlevEAAa...@fssc.demon.co.uk>, HSa...@fssc.demon.co.uk
says...
>How can I convert silver chloride to silver metal?
Here is a recipe for you to adapt:
100 g of powdered AgCl mixed with 50 g granulated zinc (not zinc dust - the
reaction may be too violent). This is then stirred into 500 cm3 of warm
dilute (2 molar) H2SO4 in a fume hood. The zinc dissolves with vigorous
evolution of hydrogen. The liquid is decanted and the solid treated with a
further 50 g zinc and 500 cm3 acid as before. When the second batch of zinc
has dissolved, then about 5 cm3 of concentrated H2SO4 is added and the mixture
heated with stirring to 90 deg C. The mixture is allowed to cool and the
silver metal filtered off, and well washed with water until no sulphate is
detected by the BaCl2 test.
Alternatively you could dissolve the AgCl in photographic fixer and use a
commercial device for recovery of silver from photographic waste. You may
also find that a company dealing in silver will be happy to accept silver
chloride as is.
Martin Pitt
University of Sheffield
John Humphrey
In article <3314ED...@ix.netcom.com>, Uncl...@ix.netcom.com
says...
>
>Herbert M Sauro wrote:
>>
>> I have a source of Galena (lead ore: PbS + impurities), actually I
live
>> over an old silver-lead mine - or so they say. Now I fancy: 1.
assaying
>> for the silver content; 2. If there is sufficient silver have a go
at
>> extracting some of the silver as silver metal.
>>
>> Q. How do I go about extracting silver?
>
>Paracelsus published about the cupel in the early 1500s. It still
>works.
>In fact, it is preferred as a cheap and easy assay for gold and
silver.
>
>Get a current silver quote from your newspaper. Think of it as a
hobby
>rather than an income stream.
option on mining a galena/silver property. Under the regulations in
British Columbia, we may mine up to 1000 tons of ore per year without
public hearings or formal permits, its considered bulk sampling. We
must keep the mines inspector happy with our work in all respects. I am
unfamiliar with the regs where you are but you should check as its
probably similar.
We live within a short (2 Hrs) truck ride of the Cominco smelter.
Cominco charges $275 Can. (floats with lead price) for basic smelting
and pays 83% of the silver values. For galena thats is 800 pounds lead
to the ton, that pays smelter fees, leaving the silver as profit,
before mining expenses. the ore at the property we are going to work
has historically been fairly rich.
If your samples assay out at anything above 25 Oz/ton you have a very
profitable one man operation. Todays quote for silver was $5.32 US per
oz.
1000 tons at 25 /ton is 25,000 oz. at $5.32 per thats over $250,000
per year, Galens is soft and easily mined, and if in massive lodes will
not need concentration.
tahator...@gmail.com
my email:a_rahi...@yahoo.com