Melting Gold - blonde needs advise

Very fine placer gold.

Steve R.

Reply to
Udie
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Hi Ken... I liked your little explanation here, and want to chat more with you in private if I may... write to me, snipped-for-privacy@dawnmist.demon.co.uk speak soon I hope Heather

Reply to
Heather Coleman

Interestingly, very few metals will stratify when once alloyed. Silver will separate from iron, but not if gold is present. Gold and iron readily form an alloy, although it has poor qualities.

The precise method for separating gold from other elements is not difficult, but it does require the use of three acids, nitric, hydrochloric, and sulfuric. I'd willingly provide a very satisfactory chemical process to anyone so interested. I refined gold for over 20 years before selling my refining business when I retired back in '94. I was fortunate to have a loved hobby turn into a business, getting me off my machines after 26 marathon years of machining.

Harold

Reply to
Harold & Susan Vordos

I'd very much appreciate you posting for us the chemical process for removing gold from alloys.

Thank you for your time.

Reply to
JoeMorgan

Check these guys out:

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If you don't need fabricated gold (sounds like you don't) you might consider buying gold bullion coins/bars. You won't be charged VAT on them and you also pay quite a bit less without the alloying/fabrication. You'll end up paying less for 24k coins than you wold for fabricated 18k (don't even think about 9k)

Reply to
bob mologna

What about buying gold coins? Most of the new ones trade at about the cost of the gold.

Dan

Reply to
Dan Caster

Hi Joe,

I'm not sure that posting this information would be the best way to go. The process is extensive if you desire enough information to actually do the refining, so the post would be a lot more like posting a book. There are a lot of steps along the way that should be described in order for the process to be successful. If, however, you are more curious about what is done, and not necessarily why, then I could probably cut it down to a couple of pages, maybe even less.

Because all the metals encountered in alloyed gold don't behave the same way, you have to jump through a few hoops to get to the gold. The main culprit in yellow gold, silver, makes the separation impossible if you do not follow the right procedure. Also, because the platinum group is often encountered when refining, the process is far more involved than may be apparent. Depending on the nature of the material being refined, there are various processes that, while they resemble one another, are different from one another. Processing filings from a jeweler's bench is different from processing old rings, for example. Different yet again for polishing wastes.

If you'll give me an idea what interests you, I would be willing to provide more information, but hesitate to spend days typing, only to find that you were more interested in a Reader's Digest version to satisfy curiosity. It would be likely that I would send the information directly to you instead of posting.

Harold

Reply to
Harold & Susan Vordos

Always add Aqua would screw you up pretty good.

Reply to
clare

.... and just when I was doing *so* well, too...... :-) Ken.

Reply to
Anonymous

That is also not the only way to do it,

An explanation of several methods is at

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"Harold & Susan Vordos" wrote:

jk

Reply to
jk

Nice explanation of various processes, but nothing unknown to me. The process very best suited to refining at a home level, aqua-regia, is the one I used in my business, although all of them mentioned were well known and understood. They, for the most part, would not work for a small producer, nor would EPA enjoy what you would be doing. . How many people do you know that want to work with chlorine gas (Miller process)? How many have a cupel furnace, especially one large enough to effectively cupel anything beyond small buttons? That system is as old as the hills, but has been used primarily for assaying. It does not lend itself well to production, if for no other reason, it does not remove the platinum group. Dumping of lead into the atmosphere is also not something that would be acceptable today. The cupel does NOT absorb all the lead. The shortcomings of the Wohwill method were well covered, and are true.

Precipitating pure gold is no chore, there are many reagents that will do the job, but the one that makes most sense wasn't mentioned in your referenced article, although I could have easily overlooked it. SO2 is the reagent of choice for anyone serious about precipitating gold. It has one real advantage, that being to be very selective, and to not add volume to a solution. That's a serious concern when you're dealing with large amounts of gold. On a small home level, where one may not wish to buy a cylinder of SO2, one would likely use ferrous sulfate in solution to precipitate.

Harold

Reply to
Harold & Susan Vordos

Aiiiiee! Sulfur dioxide is probably worse than chlorine gas. The local haz-mat squad would *not* be happy.

Jim

================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================

Reply to
jim rozen

I must admit getting a snoot full was less than a pleasant experience. If I understand it correctly, you combine SO2 with (2) H2O and end up with H2SO4, so the effects on lungs is less than desirable, but I'm still thinking that chlorine is far worse. Having grown up in a smelter town, the smell of sulfur dioxide was routine.

I had my SO2 plumbed with copper tubing so the tank was at a remote location. A stainless valve at my fume hood gave ready availability, and anything that spilled went through the filtered hood and was discharged outside. I rarely came in contact with it.

Refining isn't for the feint of heart. Of necessity, you work with all kinds of hazardous chemicals, so SO2 seemed pretty benign by comparison.

Harold

Reply to
Harold & Susan Vordos

SO2 + H20 = H2SO3, hydrogen sulfite (sulfurous acid). It will, however, oxidize with oxygen: 2SO2 + O2 = SO3 And thus SO3 + H20 = H2SO4, sulfuric acid.

Now that stuff is unpleasant, and I should know, as a few days ago I was calcining some epsom salts (MgSO4 + 7H20), which results in MgO, so the product must be SO3. *That* is irritating. Good thing it was only a small amount.. note to self... burn out suspicious stuff *outdoors*...

I think SO3 is a solid at room temps.

Tim

-- "That's for the courts to decide." - Homer Simpson Website @

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Reply to
Tim Williams

SO2+H20 => H2SO3 which is Sulfurous not Sulfuric acid. Still, not nice to breathe.

Ted

Reply to
Ted Edwards

From further processing my spent solutions to extract the platinum group when concentrations levels were too low to precipitate them by other means, the solutions were generally placed in a vat with scrap steel, which would make a full recovery of the platinum group metals. The waste from this operation was further processed, which is not the point here. The point is that when the solution, which was saturated with SO2, was applied to the scrap steel, there was considerable evolution of hydrogen, witnessed by the very occasional minor ignition of the gasses. All of this was done inside a fume hood, so there was little danger of a serious fire, or an explosion. The end result was a fairly large amount of sulfur, which indicates that you are correct.

Entirely possible that in my particular process, I never experienced this. I guess it's safe to say I wouldn't know it if I did, for that was not my objective, and it certainly wasn't a problem that I had to address.

Sometimes that's not good enough, either. All depends on the wind, doesn't it? I miss my fume hood more than anything I've ever left behind. I found I used it for a lot of things that were a nuisance to endure.

That may be the case, but everything I did was in solutions, so, assuming it is soluble in water, I never saw it in that form.

Harold

Reply to
Harold & Susan Vordos

You could try Johnson Matthey I don't know their address but 40+ years ago they had a factory unit on the Wembley Park trading estate.

Reply to
Neil Ellwood

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