Does copper only knock out gold or does it also knock out silver?

[ólom]

??
So you save sulfuric by using sulfuric?
So why do you plan to use Sulfuric?

Refining twice, I agree with.
And since you did not use Sulfamic I even agree with using a drop or two to remove Lead.
But I don’t see another use of it now.

And I thought the plan was to set it aside until you have studied enough to understand the processes.

I'll just put it aside as we discussed. But I have gold dust from a long time ago, that's why I asked about sulfuric acid. But this is just a plan that I want to implement in the future.

 

[chrundle_the_great]

Search the forum for Stannous test.
How can you know what to do if you don't know what you have in solution?
You definitely don't have much Silver, if there was it would be left on the bottom.
Testing is simple, take a ml or so and add a few grains of Salt, if it creates a white fluffy precipitate it has Silver in it.
But there shold not be, since there is HCl in the AR.

Can it be regular salt or does it have to be ionized salt? If it makes a difference how come, and what happens if you don't use the right kind?

 

[Yggdrasil]

Can it be regular salt or does it have to be ionized salt? If it makes a difference how come, and what happens if you don't use the right kind?

Any Chloride will do, it is the Chloride Ion that does the job.
Even chlorinated water will do the same

 

[ólom]

That should be safe to do, you will probably need to re refine it at a later time,
but boil it in water and then a good hot HCl wash before a final water wash.
Dry it and store it for later.

Thanks again for your help! I managed to do it and got 6 grams of gold dust. Thanks!

 

[ólom]

How can the gold dust stuck in the filter paper be removed from the filter paper?

 

[Yggdrasil]

How can the gold dust stuck in the filter paper be removed from the filter paper?

Did you filter it ??
The procedure is to wash it, pour off wash water, add new and pour off again.
In the end you pour off as much as you can without disturbing it, then siphon off the rest.

Well since it is in a paper, cut off the surplus paper and store it in the paper.
When you do the second refine the paper will decompose in the AR.

Everything you pour off from washes and such goes into first a settling vessel then into the Stock pot.

 

[ólom]

Did you filter it ??
The procedure is to wash it, pour off wash water, add new and pour off again.
In the end you pour off as much as you can without disturbing it, then siphon off the rest.

Well since it is in a paper, cut off the surplus paper and store it in the paper.
When you do the second refine the paper will decompose in the AR.

Everything you pour off from washes and such goes into first a settling vessel then into the Stock pot.

Yes, I filtered. Thanks for the answer!

 

[ólom]

Is it silver or palladium and how can I tell the difference?

 

[ólom]

Is it silver or palladium and how can I tell the difference?

 

[Yggdrasil]

Is it silver or palladium and how can I tell the difference?

Since the letters are roman, I assume it is most likely Tin, if not it can be Silver but that is quite rare.
Pd is even rarer, so add a drop or two of HCl to one of the traces and see if it reacts.
If not add a few drops of Nitric to another trace and see if that reacts..
Add a drop of Stannous to the drops and see if it is Pd.
Where does it come from?

 

[kurtak]

Is it silver or palladium and how can I tell the difference?

More then likely it's tin plating over copper (just like gold plating over copper but tin instead of gold)

Tin plating (instead of gold plating) was very common on OLD circuit boards

There are some VERY RARE exceptions where palladium plating was used but that is mostly circuit boards made in Russia (Soviet Union countries) or very old military/aerospace boards

The first test I would try is to put a couple drops HCl on it - give it some time to react - then wipe the HCL off

If the HCl reacts with it &/or it exposes copper when you wipe it off - it's tin

Kurt

 

[ólom]

Thank you for your answers! I don't know where it's from.

 

[ólom]

The hcl did not react with it, the nitric acid started to dissolve it. I can't do a stannous chloride test because I'm not at home.

 

[Yggdrasil]

The hcl did not react with it, the nitric acid started to dissolve it. I can't do a stannous chloride test because I'm not at home.

Already??
How much time did you use for the reaction?
I would at least given it half an hour.
Are something left behind?

 

[Yggdrasil]

The hcl did not react with it, the nitric acid started to dissolve it. I can't do a stannous chloride test because I'm not at home.

Just to make sure , you should ad a grain or two with salt to see if it creates a fluffy salt,
Then it may be Silver.

 

[ólom]

the back

 

[ólom]

Already??
How much time did you use for the reaction?
I would at least given it half an hour.
Are something left behind?

I didn't leave much time for the reaction

 

[Yggdrasil]

I didn't leave much time for the reaction

Which means it could well have reacted with HCl. Cold HCl are not very reactive.

 

[kurtak]

Ok - I just took a closer look at the traces on these boards - this time I enlarged the pics for a better look - They are clearly not silver &/or palladium - clearly tin & because of their age (VERY OLD) maybe even tin/lead

The tin (&/or tin/lead) was applied by a wave soldering method (molten solder applied to the traces)

This is clearly evident in that with a close up (enlarged) look at them they (the traces) are raised up & rounded over - so they are not even really plated - evident by the molten solder applied to them

Even the traces that are flat(er) are clearly tin (these traces are likely plated) --- the dead give away is the fact that many of the traces have "breaks" in them where the tin has etched/corroded away &/or etching/corroding on the edges of the traces over MANY years of exposer to normal atmospheric conditions --- silver &/or palladium would NOT do this

Tin plating &/or wave soldering was VERY COMMON with OLD circuit boards

There is no need to test these boards (for silver &/or palladium) any further --- they are VERY clearly tinned

Kurt

 

[Shark]

This is a good example of why high quality pictures are ask for so often. If a good picture is worth a thousand words then a poor quality picture is like a thousand misspelled words.