I wonder if anyone could help with ideas about reclaiming
precious metals? I've been given a heap of old PC-boards and
told that the very fine wires and other connectors are either
fine gold or plated with it. Is there an easy way of removing
this, with acid or anything?
Also, I've wondered, when etching silver in nitric acid, can
that "lost" silver be reclaimed again? When I first learned
metalsmithing, I bought sterling silver from a lady who
reclaimed from X-Ray plates. Never thought at the time to ask
how it was done, and now she's gone off to be a witchdoctor!!!
Does anyone on this forum know?
I'd be most grateful for any pointers, but unfortunately book
references don't help much, since good technical books are as
scarce as hen's teeth here in Africa.
I have run searches on Orchid and other Search engines, without
any luck. Thanks in advance for any help/ bright ideas.
For reclaiming silver, the cost is going to be more than what
the silver is worth unless have an enormous amount of it. For gold
and platinum go to a commercial refiner. You can find them in
jewelry magazines. I am sure that there will be a number of them
in South Africa. There are a number of small refining systems
available for personal use, but I have found that you need to
refine a several ounces of metal (8 or 10) to make the cost of
chemicals be better than what you would pay a commercial refiner.
G'day, Vira: You can dissolve gold in aqua regia, which is 4
parts of hydrochloric acid to 1 part of nitric acid; warming -
not boiling! helps, but it takes a while.
V> Also, I've wondered, when etching silver in nitric acid, can
V> that "lost" silver be reclaimed again?
Yes it can indeed. My wife, who was in charge of a 400 student
laboratory at a university reclaimed kilos of the metal, (large
amounts of silver nitrate are used in analytical chemistry.)
when the American, William Bunker Hunt attempted a 'corner' on
silver, and silver nitrate rose in price to $500 a 500 gram
bottle! She had all silver-containing solutions and precipitates
set aside, and precipitated silver as silver chloride by adding
common salt solution. (sodium chloride) She dissolved this in
potassium cyanide solution (about 5% - it isn't important) and
using a car battery, passed an electric current through the
liquid with two bits of scrap stainless steel as electrodes.
Pure silver deposits on the negative electrode and may be easily
peeled off. In Jean's case, she then re-dissolved the silver in
nitric acid and crystallised out the pure silver nitrate - back
where they started, ready for use in the labs again.
In your case, you could try passing the electric current through
the silver nitrate solution directly, though I'm not sure if it
would work: both silver and gold deposit best from cyanide
solutions. In the case of the auric (gold) chloride from the
acid aqua regia, you could neutralise the acid with caustic soda,
add a little sodium or potassium cyanide, and plate-off as
In the case of silver nitrate, you could neutralise that with
caustic soda or potash, add some cyanide and plate-off the pure
silver. But do NOT ADD CYANIDE TO ACIDS!! - it's very bad for
your continued living! On the other hand, don't be unduly afraid
of cyanide - just use common sense and be careful not to ingest
it or get any in a cut.
But don't expect to get much gold from PC boards - it is a bare
flash, so little you can't measure it easily without very
This is a statement of what can be done, Vira. If you want a
detailed plan of how to recover the metals, do email me
directly, telling me exactly what you start with. Finally, you
could etch your silver electrically anyway.
/ / John Burgess,
/ //\ @John_Burgess2
/ / \ \
/ (___) \
Where are you in Africa? If you are near the medical school or
a hospital, the Radiology Department can tell you who reclaims
their silver. However, they usually do large lots and get cash
for the silver. Then contact the reclaimer; the head of the
department will tell you who it is.
Be careful--sometimes silver is stolen by an employee--make sure
you know from whom you buy. Receiving stolen property (reclaimed
silver) is usually a felony.
I am a retired radiologist. Before you buy silver reclaimed
from x-ray "plates" (actually it is reclaimed from the used x-ray
film), I would be very careful to have the consent of the
radiologist from whom the film was taken. Reclaimed silver is
considered the property of the radiologist or Radiology
Department. The money from its sale, usually to a professional
reclaimer, is considered part of the film budget. Sales
anywhere else is often a result of theft.
One hospital in LA had its whole CURRENT film library stolen
(that means YOUR current mammogram, too), probably to be sold for
silver, since there aren't any known x-ray fetishists around.
Well, maybe radiologists.
I am sure you don't want to be arrested for receipt of stolen
property. Know where the silver came from. Call them to be
sure this person had the authority to sell it to you.
I have done some refining with some of the "non-toxic" refining
systems available. Not very sure about the non-toxic part of it.
All aluminum with 10 feet usually turns to dust. Maybe I did
something wrong? And some of the odors coming out of it are
enough to empty the building! But it does work very well. Maybe I
worry too much, but I just do not like cyanide solutions much. I
got rid of all my cyanides long ago. Seems to be about the most
toxic stuff there is. I know a few people that killed by that
stuff. I am sure that it was from improper use. Problem is that
it sure seems to make mistakes with it and I have to hear of a
non-fatal cyanide mistake. I know that it is perfectly safe when
proper precautions are taken, but I would just rather not mess
with it. Seems that for most applications it can be substituted
with chemicals that are far less lethal. But I have to admit that
it has no equal for cleaning precious metals! A few minutes in
cyanide does wonders on discolored gold or silver chain. And I
have to repeat to anyone hearing this, NEVER MIX ACID AND
CYANIDE. You will be dead before you realize your mistake. I have
to ask, is it true that long term exposure to cyanide causes
intensely blue eyes? I have heard rumors but have never been
able to talk with anyone that could confirm this.
Thank you all for your responses to my question about reclaiming. I think
been scared off, with all the inherent dangers of cyanide, which I don't
is freely obtainable by individuals here anyway.
I think I'd rather just stay with my normal metals supplier. Just had
of all the professed gold on those PC boards being thrown onto the scrap
Reclaiming would probably be more trouble than its worth , by the sounds of
Doc Carrie, thanks for the warning. I had no idea!!! I think - I hope - the
lady in question was above board, since she was also selling to the local Gem
and Mineral Club. Just shows, one must be very aware at all times.