One more query please? Why does cupelled button go from a bright red , ( think I know this one ) , to a bright golden sheen , then it cools completely to a dull lead/ silver finish?
Thanks again
Thanks again
From bright gold button to dull silver colour?
- Thread starter drtys
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Assuming the temperature is not way above gold m.p., this means you have 30% or more silver
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Upon final cupeling off of all PbO, the final "blicking" of the bead occurs from the rising temperature, which occurs at this moment. The final cooled bead will vary in color, depending on the Silver content. This is where inquarting, and parting with Nitric come into play, to determine Au only weight. Although the Au could still have other PGMs included with Au after parting. This is why most good labs will send through AA to see if other PGMs are included.
hello again, we cupelled a lead collector button, we had two actually, which were a bright yellow/ golden colour, once they cooled down , both were placed in some muriatic acid , as well as some of the cupel crust sections which had some beads imbedded, after about twelve hours, there was no sediment/ dust or solids left in the container that had the acid in it, but the acid is a bright yellow colour. Any thoughts as to what occurred? Thanks once more.
Attachments
I have moved your post here, it belongs here, do not spread threads around when they are a continuation of something else.
And please do not write whole posts in bold or all caps. It is considered shouting and may be seen as impolite.
Where did the button come from?
Ores, scrap and so on?
Unless there are oxidizer present HCl will not touch Gold and it will never touch Silver.
So one out of two, there are no PMs in the button or you have a lab Goblin/Troll eating your PMs
Joke aside, test with Stannous and see, but my guess is there is no PMs
Yellow is common for Iron compounds.
Ores, scrap and so on?
Unless there are oxidizer present HCl will not touch Gold and it will never touch Silver.
So one out of two, there are no PMs in the button or you have a lab Goblin/Troll eating your PMs
Joke aside, test with Stannous and see, but my guess is there is no PMs
Yellow is common for Iron compounds.
Thank you sir for both replies, I get the point on the first, dunno why the bold came out like that, as for the second , my buddy knows a lot about a lot, but nothing of chemistry and such, I am hoping that your replies and information will help corroborate what I am trying to get him to understand as well as educate myself and yes back to more reading in the library section lol. Much appreciate the input.
I found a puddle of lead not long ago, i wanted to vaporize a small amount but ended up tossing it into the acid after 85% vaporized, then disposing of it all, however, the lead had the same golden tint/foils over it, and did look like gold for few whiles, i don't blame it on the lead, but i can definetly blame it on impure gas.
Martijn
Well-known member
Lead usually does not hang out in puddles, but in solid state.
What do you mean 'found a puddle of lead'? I'm almost thinking mercury.
I also think it's a translation thing, but please clarify.
How have you vaporized lead? Have you scrubbed the fumes?
How did you 'dispose' of it?
"The acid"? Which one?
Don't blame the lead, it didn't do anything wrong, you gave it wrong instructions.
TO ALL NEWBIES: before you do anything, ask us first!!!! for your own sake and everything around you.
What do you mean 'found a puddle of lead'? I'm almost thinking mercury.
I also think it's a translation thing, but please clarify.
How have you vaporized lead? Have you scrubbed the fumes?
How did you 'dispose' of it?
"The acid"? Which one?
Don't blame the lead, it didn't do anything wrong, you gave it wrong instructions.
TO ALL NEWBIES: before you do anything, ask us first!!!! for your own sake and everything around you.
It might be helpful to determine the source of the metal before taking any further action. Additionally, it's worth noting that the presence of palladium can cause gold to turn white in color. One way to gain more information is by dissolving a small piece of the material and performing a Stannous Chloride test. After conducting the test, it would be beneficial to share the results with others by uploading a photo or description of the color observed. Without additional data, any conclusions drawn are simply guesses.
I knew I had a reply missing but it is only today I see your message.
By puddle i simply meant a big solid piece of lead with a weight of 23 kg +-500g.
I didn't fully vaporize it i done it in a tiny mould for precious metals with a hand torch.
I tossed it along another piece after i reduced it's size by 75% in hcl with some peroxide.
Not blaming the lead i were simply uncertain if it contains any other metal but it reacted and behaved just like the other one.
That is completely insane!
How much waste did you create?
Lead by itself is toxic, but possible to manage.
Now you will have who knows how many liters of extremely toxic Lead salts which is an order of magnitude more toxic than metallic Lead.
How are you going to dispose of this?
He could try to cement it out first. Check the Redoc Metal Series for a suitable precipitant:
Any other ideas, or comments?
@andu: Chose a pure metal that is below Lead like Nickel f.e.:
Even H2O is supposed to precipitate Lead in solution, but I am unsure if that really works in this case.
Worth a try. Please report back.
No copyright problem here, this is from my own book "Gold Hunter´s Guide"
Any other ideas, or comments?
@andu: Chose a pure metal that is below Lead like Nickel f.e.:
Even H2O is supposed to precipitate Lead in solution, but I am unsure if that really works in this case.
Worth a try. Please report back.
No copyright problem here, this is from my own book "Gold Hunter´s Guide"
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kurtak
Well-known member
Just to add to this - when stannous testing a solution with both gold & palladium dissolved in the solution (you know there is gold but unsure of Pd) the gold should be precipitated from the solution before stannous testing for Pd --- otherwise the purple/black gold result is likely to mask the green/black of the Pd (so though not a false positive - a confusing result)
Or - if you are going to test for Pd before precipitating the gold then a DMG test first
Kurt
To COMPLETELY get lead out of an aqueous solution, he'd need to add sulfuric acid. Lead sulfate is virtually insoluble in acidic aqueous solutions. It's a step that's essential for gold purification, for example; one that Sreetips has demonstrated many times.
But he would also have to know how to handle sulfuric acid. It's very dangerous to anyone not familiar with the methods of storing and handling it.
Did you read what that poster did?
He more or less dissolved 75% of 23Kg of Lead in HCl.
It have to be a massive amount of LeadChloride, and as Alondro says, maybe the best is to drop it as Sulfate and hand it in as Special waste.
I think he don't need Sulfuric acid, Magnesium Sulfate will do I think.
If he could form lead carbonate, that's a full order of magnitude LOWER in solubility than even lead sulfate. Only 0.00011g/L.
But it's tricky. One must add chilled ammonium carbonate solution and keep the reaction cold.
Easy is best here, the poster is fresh and has not worked up much lab skills yet.
The sulfate is the easiest and after initial drop he can let it evaporate naturally which will drop even more over time.
With summer coming on, the sulfate should dry pretty quickly too. The issue with letting ALL the solution remain is that the chloride will still be in there. Then he wouldn't want to use magnesium sulfate, because that would yield a large amount of magnesium chloride, which is quite deliquescent (due to MgCl2 being a Lewis acid) and will never dry.
I'd assume sodium sulfate would work too. At least sodium chloride resulting from that exchange reaction would dry under hot summer sun.
Nonononono ya'll got me wrong, out of the 23kg of lead i took two tiny pieces of few grams of it. I disposed of it on the local waste management facility after neutralizing the solution (and pouring some iron solution in case it precipitates but didn't get to see it) and properly write on it what it contains. I evaporated 75% of one of those two tiny pieces which i then threw in the same acidic solution to see if it reacts and looks the same after few days, which it did. I would of used sulfuric for precipitation .
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