Solution get darker after gold precipitation

[orvi]

And here is more concentrated PtPd solution (AR) after one drop of SnCl2 test solution. Colours get deeper, green Pd stain is much more evident and even after putting the drop in, you can see some nearly brownish-dark edges. But as it diffuse, it lose that tinge and become regularly green again. Platinum is obvious and deep orange.

I do not have pure Pd in hand now. It can be difficult to spot Pd in green solution of Cu or Ni. Better to test for Pd with DMG in these cases.

 

[orvi]

Than why are these rams so expensive. Is there any other metal in Rams? I got 100 mg of gold from 165 gm ram IC chips. Is that also ok number? Total 1kg rams. 165 gm IC chips and 835 gm rams.

Depends on what chips are on them. BGA ones can be pretty rewarding. Altough classic SMD two-side legged chips usually do not yield that much. And if you account ones that do not have gold bonding wires inside... You are going steep under 1g/kg

 

[Shark]

Some great pictures orvi, thanks.

 

[Hurc]

Depends on what chips are on them. BGA ones can be pretty rewarding. Altough classic SMD two-side legged chips usually do not yield that much. And if you account ones that do not have gold bonding wires inside... You are going steep under 1g/kg

Thanks Orvi. I understand the Stannois results. But to vet confisent in it. I need experience. I am using DDR2 rams so there ic chips do not have two sided legs.

 

[orvi]

Some great pictures orvi, thanks.

Thanks. I choose the watchglass method, since it is more clear in terms of colour (in my opinion).

It needed some visual for beginners to see

 

[Hurc]

Thanks. I choose the watchglass method, since it is more clear in terms of colour (in my opinion).

It needed some visual for beginners to see

What I understand is to check whether stannous test is false positive or not we pour more sncl2. If the colours fade away it means false possitive. In case of PGMS increase in SnCl2 will not affect colours. Am I right? To distinguish between colours need experience. Pics you shared clear mamy doubts. Thanks

 

[orvi]

What I understand is to check whether stannous test is false positive or not we pour more sncl2. If the colours fade away it means false possitive. In case of PGMS increase in SnCl2 will not affect colours. Am I right? To distinguish between colours need experience. Pics you shared clear mamy doubts. Thanks

Black-violet colouration when gold is present just get more diluted, when you pour more SnCl2. Same with palladium and platinum. If too much SMB was added, false positive brown colour can stay in solution for quite a long time. But now you would be able to recognize it, because it´s different colour.

 

[Shark]

I have never used SnCl2 in the way Hurc is using it. I only use one or two drops of my solution and one or two of my SnCl2. I usually use a q-tip unless it gives me problems in determining the results. Then I use a spot plate, or a white plastic spoon.

 

[orvi]

I am also using one/two drop max, for the photos I overexaggerated just for the better illustration. It is wasteful to use that quantity of solution in my opinion.

 

[BlackLabel]

Hurc,

For me, it looks like your green liquid in this video is full of crystals. (SMB?)
https://goldrefiningforum.com/threads/solution-get-darker-after-gold-precipitation.31239/post-328630If your test drop is full of something, your test solution will show something.

Don't take the liquid for testing from the bottom of the beaker.

 

[stella polaris]

If processing the whole ram card, - chips, it might be some tiny MLCC containing palladium at the board. Perhaps this is enough to give indication for palladium.

 

[Hurc]

I need one more clarification please. Gold powder I got from SMB. After few days more brown powder settle down at bottom. I separate amd wash that powder with water. After that I boil this powder in HCl. All powder dissolved in HCl. I stannous test the HCl solution amd got the result as attached. Do you have any clue what is this? Does it seems gold? Why did it dissolve in HCl?

 

[Yggdrasil]

I need one more clarification please. Gold powder I got from SMB. After few days more brown powder settle down at bottom. I separate amd wash that powder with water. After that I boil this powder in HCl. All powder dissolved in HCl. I stannous test the HCl solution amd got the result as attached. Do you have any clue what is this? Does it seems gold? Why did it dissolve in HCl?

You probably have some oxidizer left in solution, so when you add HCl you re dissolve the Gold.

 

[Hurc]

You probably have some oxidizer left in solution, so when you add HCl you re dissolve the Gold.

What should I do to prevent this happened again in future?

 

[Yggdrasil]

What should I do to prevent this happened again in future?

Depending on what you used to dissolve the gold.
If AR you need to properly denox it.
Bleach or Peroxide, a good long “boil” will do it.

But usually it is not an issue, put it in your stock pot and hang some thick copper slabs in there. This will deplete the oxidizer and cement out the PMs.
It needs some kind of stirring though.