# Dore` Bars



## flexyman (Apr 26, 2008)

Hi, I am new to this very informative forum.
I recently found about 30 tons of used flux/slag stored in a barn.
The owner told me that he was hired to cleanup a site, where a Silver refinery had burned down. Somewhere near LA. I took a sample, remove
all the large pieces of metal containing I imagined Ag,Au, Cu,Pb, Pd,
Ni, Tn, Sn. then crushed the flux glass, tried to pan this, with no sucess.
As I found millions of tiny metal beads (BB`s ) I sent a sample of crushed
slag for fire assay came back 90 grams per ton Gold and 100kg Silver
per ton. This had been sitting in the barn ,in rusty 55 gallon barrels,
for25 years. I have crushed 15 tons of the slag, ran it thru a hammer mill.
To expensive to use chemical recovery at this stage. So I melted some slag and made 600 Lb od 10 Lb Dore` bars.
Happily I went , baught Nitric acid and desolved some bars, filtered dark
purple sludge. Precipitated from solution seposedly AgCl. This I
boiled in NaOH solution till White precipt turned to black, then I added
Karo and kept boiling ( brown fumes came off for a while,then stopped)
the black ?? (AgO ) turned metalic grey. I have 50 Lbs of this grey powder
I melted 10 Lbs of grey powder in clean flux. there was considerable
white fumes that came off the melt. I put a piece of cold iron plate in the
fumes and a purple colour attached itself to the cool metal. Flux turned Black and I had 6 Lbs of metal bar which had a dark grey luster to it.Not
Silevr metal I thought  
Thinking I could turn the Dark sludge to gold, I put this into A.R. Very
little disolved. So I filtered and boiled AR ( as per CM Hoke) but used
Sodium Metabisulfite. Got the familiar coppery brown precipt after cooling
the solution as well as gold , fine grey metalic needles had formed at the bottom of the beaker.
I have since found out that this refinery recovered Ag and PGM from
Jet Engine parts and computer scrap which was made into Anode bars. But further information was lost.
My problem is I have large amount of Selemiun in the Dore`.
Selenium boils at about 700 deg. C and is nearly the price of Silver
How can I separate the metals? Is there any-one on the forum with
knowledge of this. I found Stillwater Mining has Se in their Ore and
they use hot Sulfate pressure leach and precipt the Se with sulfourous
acid. I cannot find info on how to make this leaching system, for Alchemy
enthusiast

Happy refining
flexyman


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## goldsilverpro (Apr 26, 2008)

Are you the same flexyman that was on recyclebiz? If so, you might remember me - Chris Owen. In any case, welcome to the forum.



> desolved some bars, filtered dark purple sludge


This sounds like it could be colloidal gold. When the gold is low in the alloy, this is easily obtained when dissolving the silver, copper, etc. away from it. Very difficult to filter.



> I melted 10 Lbs of grey powder in clean flux. there was considerable white fumes that came off the melt. I put a piece of cold iron plate in the fumes and a purple colour attached itself to the cool metal.


Unless you use a power stirrer that provides a chopping action, it is difficult to convert all of the AgCl to Ag, using the NaOH + Karo syrup. The white fumes are likely unconverted AgCl. This is very bad to breathe. The purple on the iron could be condensed AgCl. It turns purple when exposed to light, especially when hot.

I don't understand where the Se came from. Why are you convinced that it is present. I spent quite a few years, in L.A., refining gold from jet engine parts and never ran across Se. It's usually associated, along with Te, with mining materials, such as copper ore. The gold on jet engine parts is in the form of brazes, usually 82/18, Au/Ni. One type of Au braze, found on certain rotor blades, also has some Pd in it. Ag braze is either Ag/Cu or Ag/Cu/Pd. The only Pt I saw from aircraft parts was on Pitot tubes. 

I used to work for a jet engine refiner in either City of Industry or City of Commerce - can't remember which. This may be where your slag came from. The owner, Bill Thomas, died from breathing AgCl fumes (in my opinion). He used to stand over the furnace and watch the AgCl convert to Ag.

I don't know how to separate Ag from Se. I do remember reading about methods in old mining books. The sulfate leach you speak of is probably hot concentrated sulfuric acid, which was a common (but dangerous) method for dissolving the Ag in dore' bars. Sulfurous acid is basically SO2. One of the sulfites, such as sodium metabisulfite, may work as well. I don't think a silver cell would work, because Se would most probably foul the electrolyte.


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## flexyman (Apr 26, 2008)

Hello Chris thank you , yes I am the same Flexyman. 
I sumize that the bars have Se, because I have found large quantities
of burned computer scrap. It seems as if this refinery used heat to
" sweat" metals off the jet engine parts. then I found pc boards that
were partualy burned and the transistors were partualy melted.
This Grey luster metal seems to sweat out of the Dore` because when
I cut it in half I get coppery colour center and outside skin of grey metal.
The black slag from the "Silver Powder" melt has a strange Garlicy
smell to it.

Thank you for your interest, I will try to get Pictures to post.

flexyman


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## goldsilverpro (Apr 26, 2008)

I guess there could be Se in the boards. It was used for power supply rectifiers, but it was primarily replaced by Si in the 1970s. Garlicky breath can be caused by both Se and As poisoning, but I don't know if the materials themselves would smell garlicky. I would think that As, in old boards, is more possible than Se. It was used as a flame retardant and as gallium arsenide semi-conductors.

Somewhere, I have a list of about 8 different ways to refine jet engine parts. "Sweating" isn't on the list because it's so stupid. One would be lucky to get half of the gold by sweating it off.


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## Lou (Apr 26, 2008)

It's unlikely to be selenium. Arsine gas smells of garlic, so also do you if you've been poisoned by it (quite obvious too! rampant hair loss).

Selenium metal is odourless, but H2Se is not. I was once poisoned by that very same chemical. It has a disgusting odour even worse than that of CS2. 
You can get H2Se by dissolving certain selenium compounds. I would hope that you don't encounter it, it is every bit as bad as HCN.

If it smells like rotting filth with a weird sweet note, it is probably H2Se. Vacate the area if it does.


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