Also still wondering about the continuum method. I asked this a while back and either people wanted to argue, ior they didn't understand it. This is when you fire assay material, no collector metal, then you ever so carefully dump out some slag, add more material, rinse and repeat, until you have a good quantity of gold in your crucible where any slag left not really an issue.
Tin as a Collector
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You can not fire assay anything like that.
Then you have to have a fixed amount of material and pull all the values out and measure how much you end up with.
You have to have full control of what you add.
It can be used as a production method provided the slags are thin enough and the ore itself has high enough metal content to collect the values.
Well it works since they have used it for thousands of years.
But it has to be done correct.
Anyway it gives off toxic gases and not very recommended these days.
Bismuth is such a better choice than lead for a million reasons, eventho a bit more expensive, i'd think about recovering bismuth from cupels, not so much the damn lead. Not sure if it's faster but given you can eat quite a bit of bismuth compound and all you'll get it smell-less farts, do that with lead and you won't a second time, same goes for the fumes, weakens your bones.
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Cupelling does work with lead. You say collector metal? Are you just throwing lead in your crucible btw? The standard is to use litharge and reduce it to lead in the melt. Bismuth works fine although not quite as good as lead. If you are saying that your lead doesn’t cupel with a torch then you have a reducing flame. Im just guessing and mind reading here. You were not so clear in your statement.
patnor1011
Well-known member
Kurt is right. I once sent sample of tin collected from BGA IC to Jon and he zapped it with XRF. That post is somewhere on the forum but if I remember correctly it was in region of 2g of gold per kilo.
I do have about 2 kilo of it somewhere
Since gold price is climbing nicely gold value is now much more than value of tin. Yet still if you would want to get that gold out it would be a nightmare.
I do have about 2 kilo of it somewhere
Since gold price is climbing nicely gold value is now much more than value of tin. Yet still if you would want to get that gold out it would be a nightmare.
Wouldn't a electrolitic cell get the gold efficiently if tin cells are as fast as it is said? With a bit of care ofcourse.
If you dissolved the tin completely, with oxidizer, then cement the gold, you'd still be in profit with not really that much acid.
If you dissolved the tin completely, with oxidizer, then cement the gold, you'd still be in profit with not really that much acid.
On one hand you say you cannot fire assay anything like that. Then on the other it can be used as a production method. Which is it?
Post video as proof cupeling works for you.. Anyone can say it works. If it becomes lead in the process then whats the difference if you use lead?
Doesn't work. Post a video showing how it works for you.
A fire assay is a method for analysing what and how much precious metal an ore contain.
And it has to be done with very precise and exact amounts of ore.
The moment you either remove or add anything, the said batch is useless.
Start studying mate.
It has been used for millennium so it works.
I do not treat ores so I have no need for it.
It has to have plenty of Oxygen so no reducing flame can be used and it need to have the correct stable temperature for sufficient time.
That is why they usually use electric kilns for it today.
The reason for using Litharge is that it melts at a higher temperature than most of the ore and as it melts and reduces to Lead creates a trickle stream of Lead contacting most of the ore particles as it runs down and collect in the bottom.
Using metallic Lead just let it pool up in the bottom and "never" contacts most of the ore.
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In addition to what Yggdrasil said, the Litharge is intimately mixed with the ore. This fine powder will turn into a virtual "rain" of Lead particles, when heated to around 1800 F. This allows better contact with the mostly very fine ( as in small ) Au particles, producing bigger alloy beads, which then have a better chance to settle in the crucible.
Using metallic Lead will turn it liquid at around 450 F., causing it to settle in the bottom before intimate Au particle contact. The only way then, is to swirl the hot liquid flux/ore mix, when it is at 2000 F. + degrees, to mix the Pb with the hot material, for a relatively good collection of the PMs. Not recommended, even in a solid concrete structure, wearing a fire proof suit.
Also, since an assay is performed at a temperature close to the melting point of the PM alloys, it is likely the contents of the crucible will freeze, if not poured almost immediately.
The assay business has adopted techniques developed over many 100s of years, and has used PbO as the go to collector, even in todays environmentally conscience world. Why? Because it works the best. Metallic Pb will work, to a degree, but I want my results to be as close to 100%. Especially when dealing with hard earned Au.
Although I have never performed an assay, I believe another reason for using litharge is that as the oxygen is liberated, it helps to oxidize base metals and cause them to report to the slag.
Dave
Dave
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That is true. Carbon is added in the form of flour ( like bread making type ) to reduce to Pb. Using a little excess of PbO, relative to what flour quantity is added, will report some of the base metals into the slag. Roughly 1 gram of flour will reduce 11 grams of PbO to Pb. Depending on the call of the assayer, he may use up to 45 grams PbO in a 1 assay ton charge, if there is a considerable amount of base metals, and/or sulphides in the material being assayed, while still only adding 1 gram of flour. Other carbon based substances can be used, but they have a differing reducing factor.
kurtak
Well-known member
Can you provide a link to the thread where you asked that question - I would like to read it
Kurt
It was a while back that he mentioned something he had seen, probably not on this forum.
But he needs to get some understanding of the concept, because he calls it assaying when it really may be a production method,
not very good as far as I can see.
Smelting without collector metal and raking/pouring off the slag then adding more material until you have a pool of melted metal in the bottom,
hence the name continuum method.
Here is his post: https://goldrefiningforum.com/threads/the-continuum-method.33748/post-362110
I can't see that working for other than very special cases.
I dropped a bit of tap water inside in hopes the cucl might dissolve another bit of coffee, instead, I got this milky coffee, any idea what it is? I mixed it a bit and now unnoticeable, but i don't feel like dumping it in the cucl container anymore.
Sorry for dropping in the threat with unrelated stuff.
More on point, I seen electrolitic cells work quite nicely to rid of tin.
Sorry for dropping in the threat with unrelated stuff.
More on point, I seen electrolitic cells work quite nicely to rid of tin.
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What was inside before the water?
CuCl is largely not soluble in water and will crash out as a white precipitate.
Add a bit of HCl and will clear up and become green again.
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