# Hot Lead



## Art Corbit (Jun 5, 2008)

* I finally got around to trying the molten lead to separate the fine gold from the junk. The lead did not dissolve the gold and it did not melt it like I was told it would. The gold I was using was really fine stuff and would not break through the surface tention of the lead. I stired the gold into the molten lead and the junk floated back to the top but the gold didn't.

I was working in a large table spoon so the lead was only about 1/4" deep in the center. I didn't try to pour the hot lead off and it was a good thing didn't. When the lead had cooled I flipped it out of the spoon and put it under a microscope. I could not fine a single piece of gold on the surface on top or on bottom. 

I broke the piece of lead in half and looked at the inside of it and there was the gold about half way down from the surface. I didn't keep it hot long enough for it to settle all the way to the bottom of the lead. Also You could see a small speck here and there but most of it was in a wad right in the center. If I had stirred it longer and kept it hot longer the gold would have been in a wad in the bottom. 

There is no reason you couldn't use this method to separate gold from black sand or any other junk it is mixed with. Placer gold would sink a lot faster than this scrap gold I had. A propane turkey fryer burner, a 10" cast iron skillet and about 5 lbs of lead and you could process a lot of black sand in a hurry. I can also process a lot of the fine silt from my bucket method.

Art

Art*


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## Anonymous (Jun 5, 2008)

Art, Sounds good, but how long did you give the gold to dissolve?
I think that gold should dissolve in the lead given time, as that is the basis of fire assay. But, I have not done either so I really do not know for sure.
What Karat was the gold scrap? Maybe the copper in the alloy kept it from dissolving, just a guess though.


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## Strangebrew (Jun 5, 2008)

Apologies in advance if you are already wearing a good respirator and/or doing this outside with the wind blowing away from you.

Please beware of lead poisoning from the fumes of the molten stuff. It's just too damn easy to have happen in a short period of time. 

If this is a process you intend on doing often, consider getting a blood lead level check every 3 to 6 months.

I could write a small book on lead poisoning...I've been there, and done the research when doctors didn't have a clue what was wrong.

Might be a good time for me to post some reminders on this subject on the general safety forum. All the gold on earth can't buy a new body.

Sorry to go a bit off topic.


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## Art Corbit (Jun 5, 2008)

James,

I'm not sure but I don't believe the gold is dissolved by the lead in an assay. I believe it is just melted and does not alloy with the lead. This gold was super fine and if it was going to dissolve it would have. It is real heavy plated scrap electronic gold so it is pretty close to 24K. I'm sure there was a little copper in it but not enough to keep it from dissolving if it was going to.

Strangebrew,

I have melted lead for this old cast iron sewer drain many times. Did it for years and never had any problems. Even in tight crawl spaces under houses. Lead has taken a bad wrap from people that are just repeating what they have heard or read. The trick is to not get it any hotter than you have to and melt it. Thanks for your concern but I have melted lead for about anything it can be used for most of my life and no harmful effects.

Art


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## Roxx (Jun 6, 2008)

yea and when I was in the navy we all used to jump off the coronado bridge...I did it a bunch of times....but that dosent make it any safer.

-roxx


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## Harold_V (Jun 6, 2008)

Art Corbit said:


> James,
> 
> I'm not sure but I don't believe the gold is dissolved by the lead in an assay. I believe it is just melted and does not alloy with the lead.


You are sadly mistaken. Lead is used for multi purposes in an assay. It is introduced as litharge, which liberates oxygen to help oxidize the ore, then the resulting lead, which is a powerful solvent, collects traces of values. The lead is then expelled via cupellation, leaving behind a button of values. 

If your lead wetted the gold enough for it to be captured, rest assured, some got dissolved. Given enough molten time, all of the gold would be absorbed by the lead (up to the point of saturation), in spite of the fact that you kept it well below the melting point of gold. 

If you don't come to terms with what is common knowledge, you're going to lose values. You really should read some books on gold before making these snap judgments. It is well known that gold has an affinity for lead----so much so that lead fumes are readily absorbed by molten gold. 

One more comment. That you do something that is less than wise doesn't make it wise because you do it time and again. The hazards of lead in the body are well documented and confirmed. Reminds me of a smoker-----he's sure that cancer is not attributed to smoking-----until he dies from lung cancer, anyway. 

Harold


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## Art Corbit (Jun 6, 2008)

Harold

How hot do you get an assay? I'm not melting gold. It doesn't really matter though because in your eyes I'm a stupid old jerk so I say to hell with your and the horse you rode in here on. Now if someone would kindly boot me off this forum I will go on about my business in peace.

Art


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## Shecker (Jun 6, 2008)

A process I use from time to time is a very large scorification process. I use about 20 lbs of lead. I place what I am scorifying on top and rise the temperature to about 2,000 degrees F. In the case of ores the molten lead will tear the ore apart to get at the metals and them take them in as a dissolved alloy. On pouring this lead into a mold most of the precious metals will migrate to the center of the lead because that is the hottest area. There are, however, metals that are not wettable by molten lead. Some of these are the more exotic platinum group metals (simply because 2,000 degrees isn't hot enough for them to form mixtures with the molten lead). They will form either a matte phase or remaining entrapped in the slag that is formed by the waste materials. Such mattes can very from gray to black and are themselves metallic but easily missed as slag. As an example, yesterday I fired 15 pounds of a very old complex ore (right out of the Spanish era) unto 20 pounds of lead. I recovered 16 ounces of matte material. The middle of the lead is filled with a mixture of black, gray, blue, and golden colored metals.

If one was inclined a very large cupel could be made and the lead separated from the precious metals by cuppellation. Then the lead could be recovered by breaking the cupel and smelting it with a lot of charcoal to act as a reducing agent for the lead dioxide. Just a thought.

Randy in Gunnison


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## Art Corbit (Jun 6, 2008)

Hi Randy,

Finally someone that knows something about lead. At 2000 degrees it will form an alloy but I don't go over 700 degrees. Just enough to melt the lead good and thin. That way the gold doesn't melt and it doesn't form an alloy with the lead. I was planning on a little of it dissolving but it's no big deal if it does it's still in the lead and as you suggest it can be recovered.

I think I will just hush about molten lead on this group. From some of the replies I have gotten you would think I was plotting to kill Jesus again.

Art


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## Irons (Jun 6, 2008)

I have found that native metals tend to have a patina if they have been sitting undisturbed for long periods. Impurities which oxidize and surface contaminants will all prevent or delay the metal from being absorbed into the collector.
It helps to pre-treat in these cases to dissolve or remove the contaminants.

The pre-treatment reagent would depend on the mix being treated.

Usually, the flux will take care of the problem, but not always.


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## Art Corbit (Jun 6, 2008)

That being the case I would say molten lead the way I am using it would react much like Mercury does to contamination. The gold I was using should have been pretty clean I recovered it with Nitric and then washed it in HCL to get rid of the junk. Our water isn't the best that I used to remove the acids so it could pick up something from it. I'm trying to work through this thing one problem at a time and so far I have been able to and I appreciate any good help I can get.

Art


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## Harold_V (Jun 6, 2008)

Art Corbit said:


> Harold
> 
> How hot do you get an assay? I'm not melting gold.


That isn't the point. Wave solder machines don't melt gold either, yet the solder becomes contaminated with gold. Surely you can understand that lead acts as a solvent and dissolves other elements, no different from mercury. It offers that very feature in forming solids when mixed in exacting proportions with ohter elements, none of which are melted. 



> It doesn't really matter though because in your eyes I'm a stupid old jerk so I say to hell with your and the horse you rode in here on.


I didn't say that, nor did I imply that. What I did suggest is that you research what you've been told and come to terms with the idea that you will lose some of your values to lead, even when it is held at a temperature below the melting point of gold. You don't have to like what you're told, but not liking it isn't reason to deny what is true. Don't lose site of the fact that others read these comments as well-----and deserve to be enlightened so they have an understanding of the obvious.



> Now if someone would kindly boot me off this forum I will go on about my business in peace.
> 
> Art


Your presence here is your choice----not mine or that of anyone else. You have every right to post your thoughts, and as long as you do so without personal attacks, or vulgarity, there is no reason for anyone to "kick you off". Just keep in mind that when you post miss-information, someone may, and should, clarify, so others don't get off on a tangent that is less than desirable. We're hear to teach and be helpful, not promote methods that create problems. 

Really, Art! Don't you think that if your concept was sound, it wouldn't be being used routinely now? The use of lead to recover values is not something new----it's been a part of the process of assaying for a long time. You simply have to work accordingly. 

Harold


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## Art Corbit (Jun 6, 2008)

Harold,

You keep mentioning the wave solder machine. Don't they use some kind of acid? If they do it's the acid that's dissolving the gold and not the lead by it's self.What would be the big deal is it did dissolve a little gold. It's not like you are going to throw the lead away. Even if the lead became saturated over a period of time it still isn't lost and I'm sure you could recover a lot of gold before that happened.

The biggest reason the process isn't in use now is because no one has ever gone after gold the size I am without using carbon or chemicals. I am trying hard to get the small miner off chemicals.

Art


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## OMG (Jun 6, 2008)

Keep going Art. Keep trying stuff and posting results and getting more information. Sooner or later you will either succeed or realize that you can't. You'll be learning all the way either way.
I'm interested in reading your experiments and results.
I don't think people get the idea of what you are doing. Most of the peoples posts here aren't actually lending anything that will help you prove what you are trying to prove.
The way I read it you are just density classifying, and are not concerned that lead (if it gets too hot) will amalgamate with gold.. you can get that gold back later.
If I'm understanding right, I would just continue trying to get the gold to sink, either by more vibration/stirring, getting the lead to flow thinner or cutting the surface tension down some other way.. I think I'd focus on the vibrating or shaking.. same thing that brings gold to the bottom of the pan when your panning.


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## Art Corbit (Jun 6, 2008)

I'm about to think the same thing. They are confusing what I am trying to do with assaying and it isn't the same. "Density Classifying", that's the best way I have heard it put yet. I am simply separating the gold from the lighter black sand, brown sand and silt. These people that run dredges with all the buckets of black sand sitting around should be trying to help me a little. After all they will be winners too if I can make this thing work. Most of them don't spend a lot of time on this group like some and may not even know what is going on with this.

Art


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## Irons (Jun 6, 2008)

Art Corbit said:


> Harold,
> 
> You keep mentioning the wave solder machine. Don't they use some kind of acid? If they do it's the acid that's dissolving the gold and not the lead by it's self.What would be the big deal is it did dissolve a little gold. It's not like you are going to throw the lead away. Even if the lead became saturated over a period of time it still isn't lost and I'm sure you could recover a lot of gold before that happened.
> 
> ...



The Spaniards, when exploring the America during the early years of the conquest used to bring along an 'expert assayer' because they were looking for Gold deposits. They missed a lot of good sites because the Gold was of such fine particle size and mixed with contaminants and other metals that the traditional fire assay gave a negative or minor result. Later, when Cyanide technology came along, people were able to extract the Gold.

Sometimes, a chemical extraction is the only way.


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## scrapman1077 (Jun 6, 2008)

Art, I worked for years in a company that used a wave solder machine two shifts a day. They took samples of the solder once a week and when the gold content got too high the solder had to be changed. the solder washed the plating off the component leads. they would send the solder out for refining.


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## Art Corbit (Jun 6, 2008)

Irons,

I read something along those lines a while back but I had forgotten it until you mentioned it. Thanks. From what I saw today if you stir the gold into the lead and get it down below the surface tension it should stay down and slowly sink to the bottom even if it is contaminated. After it breaks through the surface tension it is strictly SG from that point on. It looked like it is going to sink pretty slow though.

Art


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## Platdigger (Jun 6, 2008)

That could be the problem.

If it takes too long to sink to the bottom, it could be all disolved into the lead before it gets there.

What about Bismuth? Think there may be a way to use that?
Randy


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## Art Corbit (Jun 6, 2008)

Scrapman,

There again you were probably using an acid flux. You must have the third element (Flux) or the lead won't stick. It wouldn't bother me at all to send out a few lbs of lead with several ounces of gold in it. In fact I would take all of that I could get. 10 lbs of lead would hold a lot of gold dissolved or not. Just might be the best way to go. The last time I checked the better refineries only charged fro 6% to 10% and then they will buy the gold and send you a check.

Except for a trip to the bank your operation could end when you have the lead saturated with gold and shipped to the refinery. Then if the lead disolved some of the gold so what.

Art


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## goldsilverpro (Jun 6, 2008)

I agree. Flux is necessary. Probably all it takes is borax.


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## Art Corbit (Jun 6, 2008)

Hi Randy,

From what I saw today in the test it didn't look like any of the gold had dissolved. Even the real fine stuff was still there. This was the super thin electronic scrap gold so if it was going to dissolve it would have done it. In fact the lead wasn't even stuck to the gold. Some of it might melt if I got it hotter and kept the heat on it a lot longer.

There is a Yahoo group that deals with Bismuth. The best I remember they are using it along these lines but I really didn't hang around long enough to learn much about it. I do know Bismuth is a lot more expensive than lead.

Art


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## Art Corbit (Jun 6, 2008)

Goldsilverpro,

I have been meaning to ask you what part of SW Mo you are in? I am about 10 miles South of Ft Smith, AR. I have been thinking about joining the GPAA group at Fayetteville AR and doing a little prospecting with them up there. The have some places they go that is private property but they get a little gold. I would like to try my bucket method up there and see if there is any fine gold.

Art


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## Platdigger (Jun 6, 2008)

I really do hope you can get something along these lines to work Art. 
Randy


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## goldsilverpro (Jun 6, 2008)

Art,

I'm in Nevada, about 55 mi N. of Joplin, on 71.


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## Art Corbit (Jun 6, 2008)

Thanks. I'll have to look that one up on the map.

Art


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## markqf1 (Jun 6, 2008)

Bismuth does not have all of the same proprties as lead when heated.
Check into it.

Mark


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## Shecker (Jun 7, 2008)

There is a naturally occurring mineral of bismuth and gold called Maldonite. It forms silvery to black cubes. A higher gold content makes the mineral black.

Gold dissolved into lead must exceed a 14% mixture before the lead begins to show a yellow color. At 14% the lead will be gray in color and will have a match-stick appearance across it's surface (granting that the gold - lead mixture is uniform in composition). Gold dissolved into lead is a high temperature alloy -- just as gold dissolved into copper or silver or any other metal.

Randy in Gunnison


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## Oz (Jun 7, 2008)

Shecker,

You said that as rather solid in your mind. Do you have sources that you can cite of a technical nature? I am mainly referring to the details you give for changes in lead as it alloys with gold. Of course I would like to hear the rest if you have details.


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## Platdigger (Jun 7, 2008)

Sorry, but I wouldn't say gold melted into lead is a "high temperature alloy"

It was stated on another thread that: "A 15/85, gold/lead eutectic has a melting point of 250 deg. C"


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## Shecker (Jun 7, 2008)

I once found an old book from the 1920's titled "The Alloys of Lead". It discussed the appearance and properties of all of the alloys of lead and other metals. It ha a separate section on the alloys of precious metals. For those interested I found this book in the metallurgical library at the New Mexico Institute of Technology in Socorro, New Mexico (one of my former haunts).

Randy in Gunnison


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## Anonymous (Sep 21, 2008)

Has anyone gotten this to work yet?

What if you lower the heat slowly to help draw the gold to the bottom? Do you think that might work?


GM


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## Harold_V (Sep 21, 2008)

Once alloyed, most metals will NOT separate by gravity. 

No, it won't work. 

Harold


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